STX30, STX38, and STX46 Lawn Tractors TECHNICAL MANUAL John Deere Worldwide Commercial and Consumer Equipment Division TM1561 (15Mar97) Replaces TM1561 (01Sep95) and TM1418 (26Oct92) Litho in U.S.
M55912 M55913 STX38 Hydrostatic Drive STX38 Gear Drive M85680 STX38 Motorsport Edition M58333 M58332 STX46 Gear Drive STX46 Hydrostatic Drive
INTRODUCTION This technical manual is written for an experienced technician and contains sections that are specifically for this product. It is a part of a total product support program. Safety Specifications and Information The manual is organized so that all the information on a particular system is kept together.
SAFETY RECOGNIZE SAFETY INFORMATION HANDLE FLUIDS SAFELY-AVOID FIRES Be Prepared For Emergencies This is the safety-alert symbol. When you see this symbol on your machine or in this manual, be alert to the potential for personal injury. Follow recommended precautions and safe servicing practices. Understand Signal Words A signal word—DANGER, WARNING, or CAUTION— is used with the safety-alert symbol. DANGER identifies the most serious hazards.
SAFETY USE CARE IN HANDLING AND SERVICING BATTERIES USE CARE AROUND HIGHPRESSURE FLUID LINES Avoid High-pressure Fluids Prevent Battery Explosions • Keep sparks, lighted matches, and open flame away from the top of battery. Battery gas can explode. • Never check battery charge by placing a metal object across the posts. Use a volt-meter or hydrometer. • Do not charge a frozen battery; it may explode. Warm battery to 16°C (60°F). Prevent Acid Burns • Sulfuric acid in battery electrolyte is poisonous.
SAFETY USE SAFE SERVICE PROCEDURES Park Machine Safely Wear Protective Clothing Wear close fitting clothing and safety equipment appropriate to the job. Prolonged exposure to loud noise can cause impairment or loss of hearing. Wear a suitable hearing protective device such as earmuffs or earplugs to protect against objectionable or uncomfortable loud noises. Operating equipment safely requires the full attention of the operator. Do not wear radio or music headphones while operating machine.
SAFETY Using High Pressure Washers Avoid Harmful Asbestos Dust Directing pressurized water at electronic/electrical components or connectors, bearings, hydraulic seals, fuel injection pumps or other sensitive parts and components may cause product malfunctions. Reduce pressure and spray at a 45 to 90 degree angle. Avoid breathing dust that may be generated when handling components containing asbestos fibers. Inhaled asbestos fibers may cause lung cancer.
SAFETY AVOID INJURY FROM ROTATING BLADES, AUGERS AND PTO SHAFTS Direct exposure to hazardous chemicals can cause serious injury. Potentially hazardous chemicals used with John Deere equipment include such items as lubricants, coolants, paints, and adhesives. Keep hands and feet away while machine is running. Shut off power to service, lubricate or remove mower blades, augers or PTO shafts.
CONTENTS SPECIFICATIONS & INFORMATION CONTENTS Page SPECIFICATIONS & INFORMATION GENERAL VEHICLE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 3 METRIC FASTENER TORQUE VALUES. . . . . . . . . . . . . . . . . . . . . . . . . 6 METRIC FASTENER TORQUE VALUE - GRADE 7. . . . . . . . . . . . . . . . . . . . . . . . . . 7 INCH FASTENER TORQUE VALUES . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 O-RING SEAL SERVICE RECOMMENDATIONS . . . . . . . . . . . . . . . . . .
NOTES 2-2 SPECIFICATIONS & INFORMATION 3/12/97
SPECIFICATIONS AND INFORMATION GENERAL VEHICLE SPECIFICATIONS GENERAL VEHICLE SPECIFICATIONS Engine: Make . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kohler Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Command LT STX30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CV12.5—1216s STX38 (Serial No. —270000) . . . . .
GENERAL VEHICLE SPECIFICATIONS SPECIFICATIONS AND INFORMATION Power Train: (Continued) Lubrication—Input Shaft Needle Bearings . . . . . . . . . . . . . . . .Unirex® N3 Grease Only Lubrication—Transaxle . . . . . . . . . . . . . . . . . . . . . . . . . . . Shell Darina® D Grease Only Capacity—Transaxle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.64 kg (1.406 lbs) Hydro Transaxle— Make . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS AND INFORMATION GENERAL VEHICLE SPECIFICATIONS Mower Deck: (Continued) 46-Inch Mower Deck— Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rotary—Triple Spindles (Non-Serviceable) Material Type . . . . . . . . . . . . . . . . . . Stamped 2.5 mm (0.098 in.) Nominal Gauge Steel Cutting Blade . . . . . . . . . . . . . . . . . . . . . . Three—50.8 x 5 x 407.4 mm (2 x 0.2 x 16 in.) Blade Cutting Edge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
METRIC FASTENER TORQUE VALUES SPECIFICATIONS AND INFORMATION METRIC FASTENER TORQUE VALUES 4.8 9.8 10.9 4.8 8.8 9.8 10.9 12.9 4.8 8.8 9.8 10.9 12.9 10 10 5 5 12 10 10 5 Property Class and Nut Markings 10 10 12.9 12 Property Class and Head Markings 12.9 8.8 12 TS1163 Class 4.8 Class 8.8 or 9.8 Lubricateda Drya SIZE N•m lb-ft N•m M6 4.8 3.5 M8 12 M10 Class 10.9 Lubricateda Drya lb-ft N•m lb-ft N•m 6 4.5 9 6.5 8.
METRIC FASTENER TORQUE VALUES SPECIFICATIONS AND INFORMATION METRIC FASTENER TORQUE VALUE - GRADE 7 Size Steel or Gray Iron Torque Aluminum Torque N•m lb-ft N•m lb-ft M6 11 8 8 6 M8 24 18 19 14 M10 52 38 41 30 M12 88 65 70 52 M14 138 102 111 82 M16 224 165 179 132 3/20/97 2-7
INCH FASTENER TORQUE VALUES SPECIFICATIONS AND INFORMATION INCH FASTENER TORQUE VALUES 5.1 5 1 or 2b SAE Grade and Head Markings 8 5.2 8.2 No Marks 5 2 SAE Grade and Nut Markings 8 No Marks TS1162 Grade 2b Grade 1 Lubricateda Drya SIZE N•m lb-ft N•m 1/4 3.7 2.8 5/16 7.7 3/8 Grade 5, 5.1 or 5.2 Grade 8 or 8.2 Lubricateda Drya Lubricateda Drya Lubricateda Drya lb-ft N•m lb-ft N•m lb-ft N•m lb-ft N•m lb-ft N•m lb-ft N•m lb-ft 4.7 3.5 6 4.5 7.5 5.5 9.
O-RING SEAL SERVICE RECOMMENDATIONS SPECIFICATIONS AND INFORMATION O-RING SEAL SERVICE RECOMMENDATIONS FACE SEAL FITTINGS WITH INCH STUD ENDS TORQUE Stud End Tube Nut Stud Straight and Tube Nut Swivel Nut Locknut Tube Nut Stud End 90 Swivel Elbow and Tube Nut 90 Adjustable Stud Elbow Bulkhead Union and Bulkhead Lucknut Nominal Tube O.D./Hose I.D. Metric Tube O.D. Inch Tube O.D. Face Seal Tube/Hose End Thread Size Tube Nut/ Swivel Nut Torque Bulkhead Locknut Torque Dash Size in. mm -3 0.
O-RING SEAL SERVICE RECOMMENDATIONS SPECIFICATIONS AND INFORMATION FACE SEAL FITTINGS WITH METRIC STUD ENDS TORQUE Stud End Tube Nut Groove For Metric Identification Stud Straight and Tube Nut Swivel Nut Locknut Tube Nut Groove For Metric Identification Stud End 90 Swivel Elbow and Tube Nut 90 Adjustable Stud Elbow Bulkhead Union and Bulkhead Lucknut Nominal Tube O.D./Hose I.D. Metric Tube O.D. Inch Tube O.D.
SPECIFICATIONS AND INFORMATION O-RING SEAL SERVICE RECOMMENDATIONS O-RING FACE SEAL FITTINGS . Sealing Surface Special Nut Angle Fitting Special Washer O-ring Sealing Surface 1. Inspect the fitting sealing surfaces. They must be free of dirt or defects. 2. Inspect the O-ring. It must be free of damage or defects. 3. Lubricate O-rings and install into groove using petroleum jelly to hold in place. 4.
GASOLINE SPECIFICATIONS SPECIFICATIONS AND INFORMATION GASOLINE SPECIFICATIONS 4–CYCLE ENGINES - NORTH AMERICA c CAUTION Gasoline is HIGHLY FLAMMABLE, handle it with care. DO NOT refuel machine while: • • • • • indoors, always fill gas tank outdoors; machine is near an open flame or sparks; engine is running, STOP engine; engine is hot, allow it to cool sufficiently first; smoking.
GASOLINE SPECIFICATIONS SPECIFICATIONS AND INFORMATION 4–CYCLE ENGINES - EUROPE c CAUTION Gasoline is HIGHLY FLAMMABLE, handle it with care. DO NOT refuel machine while: • • • • • indoors, always fill gas tank outdoors; machine is near an open flame or sparks; engine is running, STOP engine; engine is hot, allow it to cool sufficiently first; smoking.
4–CYCLE GASOLINE ENGINE OIL SPECIFICATIONS AND INFORMATION 4–CYCLE GASOLINE ENGINE OIL SAE 5W-30 SAE 10W-30 IMPORTANT: Kohler command engines were designed and built to use multi-viscosity oil. Multi-viscosity oil is required for proper operation of hydraulic valve lifters used in Kohler command engines. SAE 10W-40 4–CYCLE GASOLINE ENGINE OIL NORTH AMERICA Use the appropriate oil viscosity based on the expected air temperature range during the period between recommended oil changes.
4–CYCLE GASOLINE ENGINE OIL SPECIFICATIONS AND INFORMATION SAE 5W-30 Use the appropriate oil viscosity based on the expected air temperature range during the period between recommended oil changes. Operating outside of these recommended oil air temperature ranges may cause premature engine failure. SAE 10W-30 IMPORTANT: Kohler command engines were designed and built to use multi-viscosity oil.
4–CYCLE GASOLINE ENGINE OIL SPECIFICATIONS AND INFORMATION The following John Deere oil is PREFERRED: SAE 5W-30 IMPORTANT: ONLY use a quality break-in oil (multi-viscosity) in rebuilt or remanufactured engines for the first 5 hours (maximum) of operation. DO NOT use oils with heavier viscosity weights than SAE 5W-30 or oils meeting specifications API SG or SH, these oils will not allow rebuilt or remanufactured engines to break-in properly.
4–CYCLE GASOLINE ENGINE OIL SPECIFICATIONS AND INFORMATION The following John Deere oil is PREFERRED: SAE 5W-30 IMPORTANT: ONLY use a quality break-in oil (multi-viscosity) in rebuilt or remanufactured engines for the first 5 hours (maximum) of operation. DO NOT use oils with heavier viscosity weights than SAE 5W-30 or oils meeting CCMC Specification G5—these oils will not allow rebuilt or remanufactured engines to break-in properly.
HYDROSTATIC TRANSMISSION OIL SPECIFICATIONS AND INFORMATION HYDROSTATIC TRANSMISSION OIL Use the following oil viscosity based on the air temperature range. Operating outside of the recommended oil air temperature range may cause premature hydrostatic transmission failure. IMPORTANT: ONLY use a quality SAE 10W-30 engine oil in this transmission. DO NOT mix any other oils in this transmission. DO NOT use BIO–HY–GARD® in this transmission.
SPECIFICATIONS AND INFORMATION HYDROSTATIC TRANSMISSION OIL HYDROSTATIC TRANSMISSION OIL - EUROPE IMPORTANT: ONLY use a quality SAE 10W-30 engine oil in this transmission. DO NOT mix any other oils in this transmission. DO NOT use BIO–HY–GARD® in this transmission. SAE 10W-30 Use the following oil viscosity based on the air temperature range. Operating outside of the recommended oil air temperature range may cause premature hydrostatic transmission failure.
ALTERNATIVE LUBRICANTS SPECIFICATIONS AND INFORMATION ALTERNATIVE LUBRICANTS MIXING OF LUBRICANTS Conditions in certain geographical areas outside the United States and Canada may require different lubricant recommendations than the ones printed in this technical manual or the operator's manual. Consult with your John Deere Dealer, or Sales Branch, to obtain the alternative lubricant recommendations. In general, avoid mixing different brands or types of lubricants.
SPECIFICATIONS AND INFORMATION GEAR TRANSMISSION GREASE GEAR TRANSMISSION GREASE IMPORTANT: ONLY use these specified greases in this transmission. DO NOT mix any other greases in this transmission. DO NOT use any BIO–GREASE in this transmission. ONLY use the following PREFERRED grease as the input shaft needle bearing lubricant: • Unirex N3 Grease®—M120263. ASTM D–1743 NLGI Grade 1 Use the following gear grease based on the air temperature range.
ANTI-CORROSION GREASE SPECIFICATIONS SPECIFICATIONS AND INFORMATION ANTI-CORROSION GREASE SPECIFICATIONS This anti-corrosion grease is formulated to provide the best protection against absorbing moisture, which is one of the major causes of corrosion. This grease is also superior in its resistance to separation and migration. The following anti-corrosion grease is PREFERRED: • DuBois MPG-2® Multi-Purpose Polymer Grease—M79292.
GREASE SPECIFICATIONS SPECIFICATIONS AND INFORMATION GREASE SPECIFICATIONS GREASE - EUROPE GREASE - NORTH AMERICA Use the following grease based on the air temperature range. Operating outside of the recommended grease air temperature range may cause premature failures. Use the following grease based on the air temperature range. Operating outside of the recommended grease air temperature range may cause premature failures. IMPORTANT: ONLY use a quality grease in this application.
SERIAL NUMBER LOCATIONS SPECIFICATIONS AND INFORMATION SERIAL NUMBER LOCATIONS ENGINE SERIAL NUMBER SUFFUX Domestic Australia Export STX38/Gear/12.5 (Steel Cam ) = 8 STX38/Gear/12.5 (Steel Cam ) = 8 STX38/Gear/12.5 (Plastic Cam ) =4 STX38/Hydro/12.5 (Steel Cam ) = 8 STX38/Hydro/12.
CONTENTS ENGINE CONTENTS Page ENGINE SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GENERAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 TEST AND ADJUSTMENT SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 REPAIR SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 TORQUE SPECIFICATIONS . . . . . . . . . . . . . . .
CONTENTS ENGINE RECONDITION VALVE SEATS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 LAP VALVES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 INSPECT BREATHER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 REMOVE AND INSTALL FLYWHEEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 REMOVE AND INSTALL CAMSHAFT . . . . . . . . . . .
SPECIFICATIONS ENGINE SPECIFICATIONS GENERAL SPECIFICATIONS Make . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Kohler Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Command LT STX30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CV12.5—1216s STX38 (Serial No. —270000) . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS ENGINE TEST AND ADJUSTMENT SPECIFICATIONS Engine: Valve Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . None (hydraulic lifters) Oil Pressure (Minimum at 1250 rpm) . . . . . . . . . . . . . . . . . . . . . . . . . . 124 kPa (18 psi) Crankcase Vacuum (Minimum At Operating Temp.) . . .25 mm (1 in.) Water Movement Automatic Compression Release Minimum Lift (Engine Cold) . . . . . . 0.25 mm (0.01 in.
SPECIFICATIONS ENGINE REPAIR SPECIFICATIONS (Continued) Rocker Arms: Rocker Arm I.D. New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.837—16.127 mm (0.63—0.64 in.) Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.727 mm (0.619 in.) Rocker Shaft: Rocker Shaft O.D. New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.837—16.127 mm (0.63—0.64 in.) Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS ENGINE REPAIR SPECIFICATIONS (Continued) Camshaft: End Play . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.076—0.127 mm (0.003—0/005 in.) Clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.025—0.063 mm (0.0010—0.0025 in.) Bore ID: New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.000—20.025 mm (0.7874—0.7884 in.) Maximum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.038 mm (0.7889 in.
ENGINE SPECIFICATIONS REPAIR SPECIFICATIONS (Continued) Piston Thrust Face OD: New: 12.5, 13, 14 hp . . . . . . . . . . . . . . . . . . . . 86.941—86.959 mm (3.4229—3.4236 in.) 15 hp . . . . . . . . . . . . . . . . . . . . . . . . . . . 89.951—89.969 mm (3.5413—3.5420 in.) Minimum: 12.5, 13, 14 hp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.814 mm (3.4179 in.) 15 hp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89.824 mm (3.5363 in.
SPECIFICATIONS ENGINE TORQUE SPECIFICATIONS (Alphabetical Order) Air Cleaner Base Nut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.9 N•m (88 lb-in.) Cylinder Head Cap Screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 N•m (30 lb-ft.) Connecting Rod Cap Screws: 8mm Straight Shank Bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.6 N•m (200 lb-in.) Step Down Shank Bolt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS ENGINE SERVICE EQUIPMENT AND TOOLS Order tools from your SERVICEGARD Catalog. Some tools may be available from a local supplier. Name Use Valve Spring Compressor Remove and install valve springs Telescoping Gauge Measure valve guides Measure inside diameter of parts. Outside Micrometer Measure valve stem Measure outside diameter of parts.
TROUBLESHOOTING ENGINE ● ● ● Fuel tank outlet restricted, shut-off valve not fully open, fuel filter or line restricted. Fuel stale, contains water, or wrong type. ● ● ● Air filter element plugged or oil soaked. ● ● ● Choke, throttle, or governor linkage worn or out of adjusted. Carburetor set too rich. ● ● ● Carburetor worn, contaminated with debris or varnish. Passages plugged. Wrong jets or adjusted too lean. ● ● Carburetor, intake manifold, or cylinder head gaskets leaking.
● Valve guides or seals worn or leaking. Valve stems worn. ● ● ● ● ● ● ● ● Worn, stuck, or broken piston rings. Cylinder bore worn. Check compression and vacuum. ● ● ● ● ● ● ● ● Connecting rod or crankshaft bearings worn. Internal wear limits out of specification. ● ● ● Engine mounting hardware loose or broken.
TROUBLESHOOTING Bent push rods after new lifters were installed Hydraulic lifters overextended. Hydraulic lifters are noisy Engine won’t shut off ● ● Inspect engine ground cable ● ● Adjust idle speed to specs. Move throttle to idle before shutdown. ● ● ● Inspect piston, valves, cylinder head & exhaust for high carbon build-up. ● ● ● Dirt in carburetor. Float sticking. Clean carb, replace filter, check float. Vapor lock. Check temperature of fuel system. Clear vent in top of fuel cap.
ENGINE TROUBLESHOOTING NOTES 4/23/97 3 - 13
DIAGNOSIS ENGINE DIAGNOSIS MAIN COMPONENTS Test Conditions: • Machine PARKED on level surface. • Park brake LOCKED. • Key switch OFF. • Transaxle/Hydro in NEUTRAL. Test/Check Point 1. Engine dipstick. Normal If Not Normal Oil level between “L” and “F” marks on dipstick. Add proper amount of oil to bring level to “F” mark. Oil not burnt or contaminated with metal particles or fuel. Change oil and filter and inspect for cause of contamination. Minimum crankcase vacuum 101.6 mm (4 in.).
DIAGNOSIS ENGINE 1 2 6 3 M55814 6 2 M55909 5 7 4 M55927 4/23/97 3 - 15
DIAGNOSIS ENGINE ENGINE HARD TO START AND/OR ENGINE STARTER KICKS OUT NOTE: Use correct starting procedure as listed in operator’s manual. The procedure of cranking the engine for 5 seconds and waiting for 10 seconds will improve starting and decrease total cranking time. The 10 second pause allows fuel in the manifold time to evaporate for improved combustion, reducing the chance of flooding and muffler backfire. Test Conditions: • Control lever in full choke position. • Crank engine for 5 seconds.
DIAGNOSIS ENGINE Test/Check Point Normal If Not Normal 6. Cylinder compression. 40—90 psi Low compression (below 40 psi) can be the result of a stuck valve or automatic compression release (ACR) not functioning correctly. A stuck valve could be caused by stale fuel or an over extended hydraulic lifter. High compression (above 90 psi) can be the result of the ACR not functioning correctly. 7. Flywheel key. Not damaged or partially sheared. Replace 8. Starter Should not kick out.
TESTS AND ADJUSTMENTS ENGINE TESTS AND ADJUSTMENTS CHOKE ADJUSTMENT Reason: THROTTLE CABLE ADJUSTMENT Reason: To make sure the throttle cable moves the throttle and choke control lever through its full range of movement. Equipment: To make sure the choke plate is fully closed when the throttle lever is in the full choke position. Correct adjustment also makes sure choke is completely open in the fast idle position. Equipment: • 6.4 mm (0.25 in.) Drill Bit • 6.4 mm (0.25 in.
TESTS AND ADJUSTMENTS ENGINE GOVERNOR ADJUSTMENT Reason: To make sure the governor shaft contacts the flyweight plunger when the engine is stopped. B NOTE: Adjust throttle cable before adjusting governor linkage. C Procedure: A 1. Move throttle lever to FAST idle position. M55933 B 2. Put reflective tape on blower housing screen. 3. Start and run engine at MEDIUM idle for five minutes. c CAUTION C A Engine will be HOT. Be careful not to burn skin. D M55935 2. Loosen nut (A). 3.
TESTS AND ADJUSTMENTS ENGINE SLOW IDLE SPEED ADJUSTMENT NON CARB/EPA (EARLY MODELS) NOTE: It may be necessary to adjust slow idle stop screw again. Reason: 11. Recheck slow idle stop screw setting. To set engine slow idle mixture and rpm. Specifications: Equipment: SLOW idle stop screw setting. . . . . . 1650 ± 75 rpm • JTO5719 Photo Tachometer Procedure: 1. Move transaxle to neutral. Engage park brake.
TESTS AND ADJUSTMENTS ENGINE SLOW IDLE SPEED ADJUSTMENT —CARB/EPA STX38 (SN 210001— ) & STX46 c ATTENTION DO NOT attempt to adjust carburetors that meet California Air Resource Board/Environmental Protection Agency (CARB/EPA) restrictions unless you are a factory trained technician with authorization to service CARB/EPA Emissions Carburetors. These carburetors can be identified by the black limiter on the slow idle mixture screw. 3.
TESTS AND ADJUSTMENTS ENGINE CYLINDER COMPRESSION TEST Procedure: 1. Move the throttle lever to FAST idle position. 2. Crank engine and record compression reading. Reason: To check pressure capacity of piston rings and cylinder bore for efficient engine operation. IMPORTANT: On engines equipped with an automatic compression release (ACR) mechanism, a compression test will indicate the ACR compression, not actual compression.
TESTS AND ADJUSTMENTS ENGINE CRANKCASE VACUUM TEST Reason: To measure the amount of crankcase vacuum, which ensures the crankcase is not pressurized. A pressurized crankcase will force oil past the seals. Equipment: c CAUTION Engine components are HOT. DO NOT touch with bare skin, especially the exhaust pipe or muffler while making test. Wear protective eye glasses and appropriate clothing. • JTO5697 U-Tube Manometer Kit Connections: 1. Attach manometer magnets to solid metal surface.
TESTS AND ADJUSTMENTS ENGINE FUEL FLOW TEST NOTE: Oil Pressure Test Kit AM122553 has been replaced with SERVICEGARD Oil Pressure Test Kit JTO7262. This kit includes an oil filter adapter and O-ring only. The hose (JTO3017), gauge (JTO7034), coupler (JTO3262), and fitting (JTO5487) are found in other SERVICEGARD test kits. Reason: To determine fuel availability to the carburetor. Equipment: • Proper Fuel Container Procedure: Connections: 1.
FUEL AND AIR SYSTEM REPAIR ENGINE FUEL AND AIR SYSTEM REPAIR FUEL TANK AND DASH PANEL COMPONENTS Dash Panel Filler Cap With Gauge (Optional) Filler Cap Screw (6 Used) Clip Nut (2 Used) Fastener Grommet (4 Used) Fuel Tank Carburetor Hose Hose Clamps (7 Used) LH Heat Shield Bushing (4 Used) Bulk Hose (Cut-To-Length As Required) Fuel Filter Fuel Shut-Off Valve Bulk Hose (Cut-To-Length As Required) Cap Screw (4 Used) Bushing (4 Used) Pedestal Hose Clamps (7 Used) Hose Clamps (7 Used) Hose Clip (2
FUEL AND AIR SYSTEM REPAIR ENGINE REMOVE AND INSTALL FUEL TANK AND DASH PANEL ASSEMBLY 1. Disconnect battery ground (-) cable. G E F M58321 D A C B M55905 9. Remove orange tab lever from throttle cable assembly (G) only if dash panel or throttle cable assembly are to be replaced. 10. Remove six screws (F) to separate tank from dash panel and cable assembly (G). 11. Remove overflow tube and fuel line, replace as necessary. c CAUTION Gasoline is explosive. Do not expose to flame or spark.
FUEL AND AIR SYSTEM REPAIR ENGINE G J I H F M58321 G M58320 14. Install overflow tube and fuel line to fuel tank spigots (H) and (J), respectively. 15. Install end of cable assembly (G) through slot (I). 17. Fasten fuel tank to dash panel with six screws. 18. Install orange tab lever on end of throttle lever assembly (G). M L N O K M58306 M58323 16. Install fuel tank lip (K) in console notches (L) while aligning six mounting holes. 4/23/97 19.
FUEL AND AIR SYSTEM REPAIR ENGINE REPLACE FUEL FILTER E c CAUTION Keep cigarettes, sparks, and flames away from fuel system. Make sure engine is cool to touch. A C D B B A M58326 20. Install left and right side hood latch brackets (E) removed earlier. 21. Connect fuel line (C) to filter (B) or fuel shut-off valve (D), if equipped, to fuel line (C). NOTE: Apply John Deere NEVER-SEEZ® lubricant to steering shaft before installing steering wheel.1 22.
FUEL AND AIR SYSTEM REPAIR ENGINE AIR INTAKE SYSTEM COMPONENTS Knob Gasket Cover Shield Gasket Stud Remove studs to remove carburetor Wing Nut Washer Grommet Stud Retaining Screw Use Thread-Lock and Sealer Foam Element Stud Air Cleaner Housing Gasket Sleeve Washer Used on stud without electrical eyelet of grounding lead Paper Element Nut Tighten to 10 N•m (88 lb-in.) M55326 IMPORTANT: Grommet must be in place to prevent dirt ingestion.
FUEL AND AIR SYSTEM REPAIR ENGINE INSPECT CARBURETOR c CAUTION Gasoline is explosive. Do not expose to flame or spark. Serious injury can result. DO NOT expose them to flame or spark. Follow the cleaner manufacture’s warnings and instructions on its proper and safe use. Never use gasoline as a cleaning agent. Throttle Shaft Seal Throttle Plate Choke Shaft Choke Spring Body Idle Screw Choke Plate 4. If inlet seat was leaking or damaged it can be replaced by pulling it out with a drill bit or screw.
REPAIR ENGINE REPAIR c CAUTION REMOVE AND INSTALL ENGINE Gasoline is explosive. Do not expose to flame or spark. Serious injury can result. Store in a properly marked, safe container. Wipe-up any spills IMMEDIATELY. 1. Turn all switches OFF and disconnect battery negative (-) cable. 7. Disconnect fuel line (E) at carburetor to drain fuel. Disconnect harness connector (G). A K J L M55812 2. Raise hood to disconnect springs (A) from mounting brackets on front tractor frame. 3.
REPAIR ENGINE REMOVE AND INSTALL ROCKER ARMS 1. Remove valve cover. A B A E B D C B Late model shown Early model differs slightly M55861 M55859 IMPORTANT: Mark push rods for assembly in original locations. 1. Remove cap screws (A), spacer (B) and cylinder head. Discard gasket and clean head and block. 2. Install new gasket with cylinder head, cap screws and spacer. 2. Remove cap screws (C) and pivot ball spacers (B). 3. Remove rocker arms (D). 4. Remove push rods (E). 5. Remove splash plate (A).
REPAIR ENGINE REMOVE AND INSTALL VALVES AND SPRINGS A M52080 B 3. Put head on a flat surface plate. Check for distortion at several points with a feeler gauge. Replace head if distorted beyond specification. E C Specification: Cylinder Head Distortion (maximum) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.076 mm (0.003 in.) D M55867 INSPECT VALVES IMPORTANT: Make sure keepers are seated in valve stem groove (D). 1. Remove carbon from valve head, face, and stem. 2.
REPAIR ENGINE ANALYZE VALVES M29934 Lead deposits on the intake valve are caused by exhaust gas leakage past the valve when using leaded gasoline. Grind intake valve and reface valve seat to correct this condition. C M29936 Use of old or stale gasoline can cause valves to stick. Gummy deposits (C) can build up on valve and can also gum carburetor, requiring cleaning. Use unleaded fuel to prevent lead deposits. Always use fresh gasoline of 87 octane rating or higher.
REPAIR ENGINE INSPECT VALVE GUIDES RECONDITION VALVE SEATS 1. Clean inside of valve guide. Standard valve guide reamer (D20020WI) can be used. 31.63/ 45° 31.37 1.5 Exhaust Insert Exhaust Valve A 34.013/ 33.987 6.970/6.988 89° 6.5 7.033/ 7.058 89° M52081 2. Measure inside diameter of guide with gauge (A). 7.033/ 7.058 B Intake Insert 45° 35.63/ 35.37 1.5 37.987/ 38.013 89° Intake Valve M52082 3. Measure outside diameter of valve stem (B). 4. An oversize valve is available.
REPAIR ENGINE LAP VALVES C IMPORTANT: Valves and seats should be lapped if they do not make good contact. M52084 M52134 3. Hold flywheel with strap wrench. Remove cap screw (C). 1. Apply light coat of lapping compound to valve face, then turn valve in seat using vacuum cup tool. 2. Check valve every 8 strokes until a uniform ring appears around surface of valve face. 3. Wash parts in solvent to remove lapping compound. 4.
REPAIR ENGINE REMOVE AND INSTALL CAMSHAFT A 3. Inspect lobes (B). Replace camshaft if lobes show excessive wear. 4. Inspect ACR mechanism (C). Replace spring if necessary and check that weight moves freely. B A E M55873 1. Rotate crankshaft to align two sets of marks (A). 2. Remove camshaft (B). 3. Inspect camshaft closely, replace as necessary. 4. Coat entire camshaft with engine oil. 5. Install camshaft with four timing marks (A) aligned. 6. Check camshaft end play. 7.
REPAIR ENGINE MEASURE CAMSHAFT END PLAY 1. Check that camshaft is seated in crankcase bore. HYDRAULIC VALVE LIFTERS— INSPECTION Reasons: A M52093 2. Measure play (A) between camshaft and straight edge (spanning crankcase) using flat feeler gauge. 3. Use shims from Shim Kit as necessary until end play is within specification. Camshaft End Play Specification (with shims): (Maximum) . . . . 0.076—0.127 mm(0.003—0.005 in.) Shim Thickness Range: The most commonly used shims are listed below.
REPAIR ENGINE 5. If engine does not turn over completely (locks up at some point), stop turning at the point of lockup and allow 10 more minutes for the lifters to bleed down. Then try rotating by hand again. Results D M52097 5. Measure inside diameter of crankcase lifter bore (D). 6. Subtract lifter OD. from bore ID. to determine if clearance is not within specification.
REPAIR ENGINE BALANCER SHAFT INSPECTION C A M52102 M52100 1. Inspect shaft for cracks and broken teeth. Replace shaft if cracked or damaged. 2. Measure journals (A). Replace if not within specification. Balancer Shaft Journal O. D. Specification New . . . . . . 19.962—19.975 mm (0.7859—0.7864 in.) Wear Limit. . . . . . . . . . . . . . . 19.959 mmA(0.7858 in.) 5. Measure balancer shaft bore (C) in oil pan. 6. Determine clearance with balancer shaft journal.
REPAIR ENGINE GOVERNOR INSPECTION To Remove Inside of Crankcase Shaft C M42195 M52105 1. Measure outside diameter of control arm shaft. Replace if not within specification. Governor Control Arm Specifications: O.D. (New) . . . 5.975—6.000 mm (0.2352—0.2362 in.) Wear Limit. . . . . . . . . . . . . . . . 5.962 mm (0.2347 in.) A 5. With a small punch, CAREFULLY drive governor shaft toward inside of crankcase to remove it. 6.
REPAIR ENGINE ANALYZE PISTON RING WEAR Rings of the wrong size or rings having improper end gap will not conform to the shape of the cylinder. This results in high oil consumption and excessive blowby. Ring end gaps should be staggered on the piston during installation. End gaps in alignment can also cause oil consumption and blowby. Vertical scratches (C) across the piston and rings are due to an abrasive in the engine.
REPAIR ENGINE IMPROPER ROD AND PISTON ALIGNMENT— C D B F A E M29947 This detonation shockwave (“hammering”) of the piston inside the cylinder causes damage to piston crown (C), top ring and groove (F), piston side skirts (E), and pin locks (D). The following is a list of possible causes for detonation: 1. Lean fuel mixture. 2. Low octane fuel. 3. Advanced ignition timing. 4. Engine lugging. 5. Buildup of carbon deposits on piston or cylinder head, causing excessive compression. 6.
REPAIR ENGINE PISTON ASSEMBLY— DISASSEMBLE PISTON RING END GAP MEASUREMENT IMPORTANT: If new rings are to be installed, deglaze cylinder so rings will seat properly. (See Deglaze Cylinder Bore, later in this section.) B A 1. Use a clean or new piston to push piston compression ring squarely into bore, to a point where it normally runs. C A D M55894 1. Remove compression rings (C) from piston (B) using ring expander. 2. Remove rails (A). 3. Remove spacer (D). M52110 F E H G M55878 4.
REPAIR ENGINE Middle Compression Ring (12.5, 13, 14 hp) . . . . . . . . . . . . 0.040—0.072 mm (0.0016—0.0028 in.) (15 hp) . . . . . . 0.040—0.085 mm (0.0015—0.0002 in.) Oil Control Ring (12.5, 13, 14 hp) . . . . . . . . . . . . 0.551—0.675 mm (0.0217—0.0266 in.) (15 hp) . . . . . . 0.176—0.026 mm (0.0069—0.0010 in.) D D M52148 5. Measure diameter of piston at point (D). Point (D) is 6 mm (0.25 in.) from skirt bottom and perpendicular to piston pin.
REPAIR ENGINE PISTON ASSEMBLY NOTE: Install piston pin before retaining ring to prevent possible scoring of bore. IMPORTANT: Side of ring marked TOP faces top of piston with Dykem stripe to left of end gap. Top compression ring has a blue Dykem stripe. Bottom compression ring has a pink Dykem stripe. A B C E D M5879 Ring Gap IMPORTANT: Retaining rings (B) should be installed with end gap (A) pointing up.
REPAIR ENGINE INSTALL CONNECTING ROD CRANKSHAFT & MAIN BEARING INSPECTION 1. Inspect for cracks or chipped teeth. C D B M55875 5. Fasten connecting rod (D) and cap (C) to crankshaft. 6. Tighten cap screws (B) to specification. 7. Check connecting rod to crankshaft side clearance. Replace if not within specification. 8. Install balance shaft, camshaft, oil pan, and cylinder head. See appropriate procedures in this section. A B C M52114 2. Check crankshaft alignment, see next heading. 3.
REPAIR ENGINE REMOVE AND INSTALL OIL PAN E A B M55945 M52116 5. Measure inside diameter of crankshaft main bearing bore (E) in crankcase. 6. Subtract journal OD. from bore ID. to determine if clearance is within specifications. Replace parts if not within specifications. Crankshaft Sleeve Bearing Bore Specifications: Oil Pan & Crankcase Main Bearing Bore ID 47.98—48.03 mm (1.889—1.891 in.) Main Bearing Bore-to-Crankshaft Clearance. . . . . . . . . . . . . . . . . . . . 0.03—0.09 mm (0.001—0.004 in.
REPAIR ENGINE 12 1 3 5 10 B 7 C 9 8 4 6 2 11 M52076 8. Install oil pan onto crankcase. 9. In sequence shown, tighten oil pan cap screws to specification. Specification: Oil Pan Cap Screws . . . . . . . . . . 24 N•m (216 lb-in.) . REMOVE AND INSTALL OIL PAN SEAL M55946 3. Using a suitable driver and disc (B), install new oil seal to specification. Specification: Oil Pan Seal Depth . . . . . . . . . . . . . . . . 2.49—2.98 mm (0.098—0.117 in.
REPAIR ENGINE OIL PUMP INSTALLATION Specification: Crankcase Seal Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 mm (0.157 in.) or until its top surface is flush with machined bore opening. A IMPORTANT: Coat inside seal lip with grease to aid installation. Install crankshaft carefully to avoid damaging seal. 4. Carefully install crankshaft seal. INSPECT OIL PICKUP E D C B B A M55874 C M55872 1. Remove cap screw (A) and plate (B) to remove pickup screen (C). 2.
REPAIR ENGINE CYLINDER BLOCK REMOVE & INSTALL 15 hp New . . . . 90.000—90.025 mm (3.5433—3.5443 in.) Wear Limit. . . . . . . . . . . . . . 90.63 mm (3.5681 in.) Out-of-Round (maximum) . . 0.12 mm (0.0047 in.) Taper (maximum) . . . . . . . . . 0.05 mm (0.0020 in.) Piston-to-Cylinder Clearance 12.5, 13, 14 hp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.041—0.044 mm(0.0016—0.0017 in.) 15 hp . . . . . 0.031—0.043 mm(0.0012—0.0016 in.
REPAIR REBORE CYLINDER BLOCK IMPORTANT: Check stone for wear or damage. Use correct stone. M85811 NOTE: The cylinder block can only be rebored to use 0.25 and 0.50 mm (0.010 and 0.020 in.) oversize pistons and rings. ENGINE IMPORTANT: Do not use solvents to clean cylinder bore. Solvents will not remove metal particles produced during honing. 11. Clean cylinder thoroughly using warm soapy water until clean white cloths show no discoloration. 12.
CONTENTS ELECTRICAL CONTENTS Page ELECTRICAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GENERAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 OTHER MATERIAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 THEORY AND DIAGNOSTIC INFORMATION . . . . . . . . . . . . . . . . . . . . . 4 THEORY OF OPERATION INFORMATION . . . . . . . . . . .
CONTENTS ELECTRICAL PTO CIRCUIT OPERATION STX30 & STX38 (SN —210000) . . . . . . . . . . . . . . . 52 PTO CIRCUIT DIAGNOSIS POINTS STX30 & STX38 (SN —210000). . . . . . . . . 54 PTO CIRCUIT TEST POINTS STX30 & STX38 (SN —210000) . . . . . . . . . . . . . . 55 PTO AND HEADLIGHTS CIRCUITS OPERATION STX38 (SN 210001— ) & STX46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 PTO CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 . . . . . . . . . . . . . . . .
SPECIFICATIONS ELECTRICAL SPECIFICATIONS GENERAL SPECIFICATIONS Battery: Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 BCI group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .U-1 CCA rating (Amps at -18oC (0oF),. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Reserve capacity (minutes at 25 Amps) . . . . . . . . . . . . .
THEORY AND DIAGNOSTIC INFORMATION THEORY AND DIAGNOSTIC INFORMATION ELECTRICAL WIRE COLOR ABBREVIATION CHART Blk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Black THEORY OF OPERATION INFORMATION Blu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Blue The theory of operation stories divide the electrical system into individual circuits by function. Each circuit is isolated from the main wiring schematic and only shows the components that are used in it.
ELECTRICAL THEORY AND DIAGNOSTIC INFORMATION READING ELECTRICAL SCHEMATICS The identifying letter is always the same for a specific component, but the identifying numbers are numbered consecutively from upper left to lower right. The terminal designation (J) is placed directly outside the symbol next to the connecting wire path. Switch positions (K) are also placed directly outside the symbol.
THEORY AND DIAGNOSTIC INFORMATION COMMON CIRCUIT TESTS ELECTRICAL Grounded Circuit: Grounded circuits usually result in no component operation or a blown fuse. Shorted Circuit: A shorted circuit may result in the wrong component operating (i.e. improper wire-to-wire contact). To test for a shorted or improperly wired circuit: 1. Turn component switch ON. 2. Start at the controlling switch of the component that should not be operating. 3.
ELECTRICAL THEORY AND DIAGNOSTIC INFORMATION NOTES 3/21/97 4-7
COMPONENT LOCATION ELECTRICAL COMPONENT LOCATION E2 Headlights (Optional) A1 Ignition Module G2 Stator M1 Starter Motor Y2 Fuel Shut-Off Solenoid (Optional) N1 Regulator/Rectifier S2 PTO Switch S5 Light Switch (Optional) E1 Spark Plug S4 Seat Switch S1 Key Switch Y1 PTO Clutch K2 Start Relay STX30 & STX38 (SN —210000) K1 Starter Solenoid S3 Brake Switch F1 Fuse or Circuit Breaker STX30 & STX38 (SN —210000) S3 Neutral Start Switch STX30 & STX38 (SN —210000) G1 Battery M55829 4-8 3/21/97
TROUBLESHOOTING ELECTRICAL Battery goes dead, discharges or Optional headlights will not turn on or will not Optional fuel shut-off solenoid will not open. Optional fuel shut-off solenoid will not close. Engine dies when shift lever is engaged. Engine dies when PTO switch is engaged. ● ● ● ● ● ● ● See power circuit test points. ● See cranking circuit test points. ● Check ground circuit test points. ● Test battery and connections. ● See ignition circuit test points.
WIRING HARNESS DIAGRAMS ELECTRICAL WIRING HARNESS DIAGRAMS STX30 (SN 010001—135159) (SN 595001—750000) STX38 (SN 010001—139615) (SN 595001—750000) S2 PTO Switch 750 S1 Key Switch 500 510 K2 Start Relay 720 520 510 520 110 S5 Headlight Switch (Optional) 941 105 110 716 800 450 716 110 Diode S1 Key Switch 715 700 200 1 710 714 100 105 715 714 941 940 2 100 F2 Fuse 800 500 650 Battery Ground 200 500 S4 Seat Switch Circuit Number Wire Size Color 100 0.
WIRING HARNESS DIAGRAMS ELECTRICAL X1 Engine Connector S3 Neutral Start Switch Y2 Fuel Shut-off Solenoid 210 N1 Regulator/rectifier 650 940 A1 Ignition Module 720 710 K1 Starter Solenoid 4 E2 Headlights 450 125 210 750 3 Y1 PTO Clutch 5 120 120 700 W1 Engine Ground K1 Starter Solenoid 3/21/97 4 - 11
WIRING HARNESS DIAGRAMS ELECTRICAL STX30 (SN 135160—160000) STX38 (SN 139616—160000) S2 PTO Switch 720 750 520 510 520 S5 Headlight Switch (Optional) 450 520 S1 Key Switch 500 510 700 510 1 200 2 710 714 100 941 715 714 500 715 F2 Fuse Holder S4 Seat Switch 714 650 800 Circuit Number Wire Size Color Termination Points Circuit Number Wire Size Color Termination Points 100 0.5 Blk S1, W1 510 1.0 Yel S2, S1 105 0.5 Blk K2, W1 520 1.0 Yel S2, S5 110 120 0.5 1.
WIRING HARNESS DIAGRAMS ELECTRICAL S3 Neutral Start Switch K2 Start Relay Y2 Fuel Shut-off Solenoid 210 N1 Regulator/rectifier 940 A1 Ignition Module 650 110 110 940 941 X1 Engine Connector 720 710 G1 Battery 105 110 716 800 E2 Headlights 5 125 201 716 110 715 450 F1 Fusible Link 200 800 750 3 4 6 120 Y1 PTO Clutch 125 100 120 105 210 W2 Engine Ground W1 Frame Ground 700 K1 Starter Solenoid 3/21/97 4 - 13
WIRING HARNESS DIAGRAMS ELECTRICAL STX38 (SN 160001—210000) S2 PTO Switch K2 Start Relay 720 750 520 510 520 110 110 940 941 S5 Headlight Switch (Optional) 105 110 716 800 450 520 716 110 Diode S1 Key Switch 715 800 500 510 700 510 1 200 2 3 710 714 100 941 715 714 500 F2 Fuse Holder 715 S4 Seat Switch 714 650 800 Circuit Number Wire Size Color Termination Points Circuit Number Wire Size Color Termination Points 100 0.5 Blk S1, W1 510 1.0 Yel S2, S1 105 0.
WIRING HARNESS DIAGRAMS ELECTRICAL S3 Neutral Start Switch X1 Engine Connector 210 N1 Regulator/rectifier 940 A1 Ignition Module Y2 Fuel Shut-off Solenoid 650 720 710 K1 Starter Solenoid K1 Starter Solenoid Ground 700 130 K1 Starter Solenoid B+ E2 Headlights 6 450 125 201 210 200 F1 Fusible Link 750 4 5 7 120 Y1 PTO Clutch 130 125 100 105 W1 Frame Ground 3/21/97 120 W2 Engine Ground 4 - 15
WIRING HARNESS DIAGRAMS STX38 (SN 210001— STX46 (SN 240001— S2 PTO Switch ELECTRICAL ) ) 705 S5 Headlight Switch (Optional) 750 946 700 941 450 400 450 K1 Starter Solenoid B+ 451 K1 Starter Solenoid W1 Frame Ground 220 450 201 S1 Key Switch K1 Starter Solenoid Ground 942 941 100 710 110 400 401 105 200 201 105 700 1 200 2 F1 Fusible Link 100 945 946 S4 Seat Switch 110 Circuit Number Wire Size Color Termination Points Circuit Number Wire Size Color Termination Points
WIRING HARNESS DIAGRAMS ELECTRICAL X1 Engine Connector 940 A1 Ignition Module 220 N1 Regulator/rectifier S3 Neutral Start Switch 940 942 710 945 705 4 Y2 Fuel Shut-off Solenoid 401 3 120 125 W2 Engine Ground 451 E2 Headlights 120 125 750 Y1 PTO Clutch 3/21/97 4 - 17
WIRING SCHEMATICS ELECTRICAL WIRING SCHEMATICS STX30 (SN 010001—135159) (SN 595001—750000) STX38 (SN 010001—139615) (SN 595001—750000) 510 Yel S1 Key Switch G 100 Blk M B 940 Wht A 710 Pur S1 S4 Seat Switch Start (0pen) S2 710 Pur 105 Blk Run 200 Red Off Pur/ Blk 714 941 Yel (0) Yel 500 (1) Seat Switch Connector 700 Pur F2 Fuse 86 30 K2 Start Relay 87a Red 800 Pnk 110 Blk 105 Blk F1 Circuit Breaker 940 Wht 650 Brn E1 Spark Plug A1 Ignition Module 85 87 941 Wht Red 800
WIRING SCHEMATICS ELECTRICAL E2 HeadLight (Optional) 510 Yel 125 Blk 710 Pur S3 Neutral Start Switch 520 Yel (open) (1) S2 PTO Switch (0) S5 Headlight Switch (off) (open) (1) (0) A (1) (0) B 450 Yel/Wht E 720 Pur 750 Blu N1 Regulator/ Rectifier 210 Red 595 Brn/ Wht Blk Y1 PTO Clutch 590 Brn/ Yel U G Blk 120 Blk G2 Stator 125 Blk SE3 - Charging Circuit 3/21/97 SE4 - Neutral Start And PTO Circuit SE5 - Headlights (Optional) 4 - 19
WIRING SCHEMATICS ELECTRICAL STX30 (SN 135160—160000) STX38 (SN 139616—160000) S1 Key Switch 100 Blk G 510 Yel M 941 Wht A 200 Red B 710 Pur S1 S2 Seat Switch S2 710 Pur (0pen) Start Run Off (0) Pur/ Blk 714 F2 Fuse 700 Pur 86 30 87a A1 Ignition Module 85 87 941 Wht Red E1 Spark Plug 800 Pnk 110 Blk K2 Starter Relay 940 Wht 650 Brn Seat Switch Connector 105 Blk F1 Fusible Link (1) Yel 500 940 Wht Pur/Blk 715 Pur/Blk 716 650 Brn K1 Starter Solenoid M1 M Starting Motor Bl
WIRING SCHEMATICS ELECTRICAL E2 HeadLight (Optional) 510 Yel 125 Blk 710 Pur S3 Neutral Start Switch 520 Yel (open) (1) S2 PTO Switch (0) S5 Headlight Switch (off) (open) (1) (0) (1) A (0) B 450 Yel/Wht E 720 Pur 750 Blu N1 Regulator/ Rectifier 210 Red 595 Brn/ Wht Blk Y1 PTO Clutch 590 Brn/ Yel U G Blk 120 Blk G2 Stator 125 Blk W2 Engine Ground SE3 - Charging Circuit 3/21/97 SE4 - Neutral Start And PTO Circuit SE5 - Headlights (Optional) 4 - 21
WIRING SCHEMATICS ELECTRICAL STX38 (SN 160001—210000) S1 Key Switch 100 Blk G 510 Yel M 941 Wht A B 200 Red 710 Pur S1 S2 Seat Switch S2 710 Pur (0pen) Start Run Off F1 Fusible Link (0) Pur/ Blk 714 700 Pur 86 30 87a 201 Red 800 Pnk 110 Blk K2 Starter Relay 940 Wht 650 Brn Seat Switch Connector 105 Blk F2 Fuse (1) Yel 500 E1 Spark Plug A1 Ignition Module 85 87 941 Wht 940 Wht Pur/Blk 715 Red Pur/Blk 716 650 Brn K1 Starter Solenoid M M1 Starting Motor Y2 Fuel Shutoff So
WIRING SCHEMATICS ELECTRICAL E2 HeadLight (Optional) 510 Yel 125 Blk 710 Pur S3 Neutral Start Switch 520 Yel (open) (1) S2 PTO Switch (0) S5 Headlight Switch (off) (open) (1) (0) A (1) (0) B 450 Yel/Wht E 720 Pur 750 Blu N1 Regulator/ Rectifier 210 Red 595 Brn/ Wht Blk Y1 PTO Clutch 590 Brn/ Yel U G Blk 120 Blk G2 Stator 125 Blk W2 Engine Ground SE3 - Charging Circuit 3/21/97 SE4 - Neutral Start And PTO Circuit SE5 - Headlights (Optional) 4 - 23
WIRING SCHEMATICS ELECTRICAL STX38 (SN 210001— STX46 (SN 240001— ) ) 942 Wht 942 Wht 941 Wht S1 Key Switch 200 Red G M B A 941 Wht 400 Yel S2 400 Yel S1 401 Yel Start Run Off F1 Fusible Link Y2 Fuel Shutoff Solenoid (Optional) 700 Pur 700 Pur 100 Blk 201 Lt Org 710 Pur 750 Blu K1 Starter Solenoid Red 220 Red Red M1 M Starting Motor 105 Blk 125 Blk N1 Regulator/Rectifier X1 Engine Connector Blk Y1 PTO Clutch U G1 Battery Wht Wht G 710 Pur G2 Stator Blk W2 Engine Ground 105
WIRING SCHEMATICS ELECTRICAL 942 Wht E2 HeadLight (Optional) 941 Wht S3 Brake Switch Blk (off) 400 Yel (0) 942 Wht Red (1) Blk 710 Pur S2 PTO Switch 945 Wht/Blk Yel 941 Wht (off) (0) (1) S5 Headlight Switch 705 Pur/ Wht 700 Pur Blk (open) (0) (1) 946 Wht/Blk 450 Yel/Wht 450 Yel/Wht 451 Yel/Wht 120 Blk 940 Wht 750 Blu S4 Seat Switch X1 Engine Connector 946 Wht/Blk (closed) (1) (0) 110 Blk 945 Wht/Blk A1 Ignition Module Seat Switch Connector E1 Spark Plug 710 Pur 710 Pur 1
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CIRCUIT OPERATION AND DIAGNOSIS CRANKING CIRCUIT OPERATION STX30 & STX38 (SN —210000) Function: The cranking system is used to energize the starting motor. Operating Conditions: In order to crank the engine; the key switch must be in the START position, the PTO switch must be OFF, and the transaxle must be in neutral. The operator DOES NOT have to be on the seat to crank the engine.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch G M 941 Wht A 200 Red B 200 Red F1 Circuit Breaker STX30 (SN STX38 (SN S1 S2 510 Yel Start S2 PTO Switch Run —135159) —139615) Off (off) 210 Red (1) (0) Red B 700 Pur F1 Fusible Link Red 700 Pur 710 Pur 201 Red K1 Starter Solenoid 720 Pur S3 Neutral Start Switch Red (open) K1 Starter Solenoid M1 M Starting Motor Blk A E (1) (0) M W1 Frame Ground (SN M1 Starting Motor Red —160000) Blk 130 Blk W1 Frame Ground (SN
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CRANKING CIRCUIT DIAGNOSIS STX30 & STX38 (SN —210000) Test Conditions: • Transaxle in neutral • Key switch in run position • Park brake engaged • Meter negative (-) lead on battery negative (-) terminal • PTO switch disengaged • Meter positive (+) lead on numbered test point Test/Check Point Normal If Not Normal 1. Battery positive terminal. 11.8—13.2 Test battery. 2. Key switch terminal B.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CRANKING CIRCUIT TEST POINTS STX30 & STX38 (SN —210000) Black 1 4 Red 510 Yel G1 Battery S2 PTO Switch 5 720 Purple 710 Purple 7 200 Red 2 720 Purple 6 100 Black S3 Neutral Start Switch 9 700 Purple S1 Key Switch 3 8 710 Purple 714 Purple/ Black 500, 510 Yellow Late Model STX38 & STX46— S3 switch is labeled brake switch 710 8 Purple 105 9 Black M1 Starting Motor Red 10 200 2 Red 11 12 Red Red K1 Starter Solenoid 3/21/97 4 - 29
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CRANKING CIRCUIT OPERATION STX38 (SN 210001— ) & STX46 Function: The cranking system is used to energize the starting motor. Operating Conditions: In order to crank the engine; the key switch must be in the START position, the PTO switch must be OFF, and the brake must be ENGAGED. The operator DOES NOT have to be on the seat to crank the engine. Theory of Operation: The starting motor has a separate starter solenoid.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch ST 700 Pur A B M G 401 Yel Start Run 200 Red 401 Yel Off S2 PTO Switch Y2 Fuel Shutoff Solenoid (Optional) F1 Fusible Link (off) (0) (1) 700 Pur 201 Org 705 Pur/Wht 710 Pur K1 Starter Solenoid Red 105 Blk S3 Brake Switch M Red M1 Starting Motor (off) (0) (1) G1 Battery 710 Pur Blk 105 Blk W1 Frame Ground Ground Power Control SE1 - CRANKING 3/21/97 4 - 31
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CRANKING CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 Test Conditions: • Transaxle/hydro in neutral • Park brake engaged • PTO switch disengaged • Key switch in run position • Meter negative (-) lead on battery negative (-) terminal • Meter positive (+) lead on numbered test point Test/Check Point Normal If Not Normal 1. Battery positive terminal 11.8—13.2 volts Test battery 2.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CRANKING CIRCUIT TEST POINTS STX38 (SN 210001— ) & STX46 Black 5 705 Purple / White S2 PTO Switch 4 1 700 Purple Red G1 Battery 2 200 Red 7 710 Purple 100 Black S3 Brake Switch 6 S1 Key Switch 3 13 700 Purple 401 Yellow 705 Purple / White 14 Y2 Fuel Shutoff Solenoid (Optional) 13 401 Yellow 710 8 Purple M1 Starting Motor 12 Red 105 9 Black Red 10 200 2 Red 11 Red 3/21/97 K1 Starter Solenoid 4 - 33
CIRCUIT OPERATION AND DIAGNOSIS IGNITION CIRCUIT OPERATION STX30 & STX38 (SN —210000) Function: To create a spark that ignites the fuel/air mixture in the engine. ELECTRICAL As the flywheel turns, a magnet in the flywheel produces current in the primary coil by electromagnetic induction. When the primary current is at the highest level, the ignition module induces high voltage current in the secondary coil. The high voltage current flows through the ignition module wire to the spark plug (E2).
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S2 PTO Switch (off) (1) (0) S1 Key Switch 100 Blk 200 Red G B A S2 S1 510 Yel (1) (0) (0) (1) Yel 500 Pur/ Blk 714 S3 Neutral Start Switch (closed) (0pen) Run Off 710 Pur S4 Seat Switch Start F1 Circuit Breaker 720 Pur E M 941 Wht B A 650 Brn Seat Connector 110 Blk 105 Blk F2 Fuse F1 Fusible Link 87a 201 Red 86 30 K2 Starter Relay 87 800 Pnk 85 941 Wht V1 Diode Pur/Blk 715 Red Pur/Blk 716 650 Brn K1 Starter Solenoid 940 Wht
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT DIAGNOSIS STX30 & STX38 (SN —210000) When diagnosing an ignition problem, isolate the magneto circuit from the ground circuit by separating the engine connector. If the engine will not start check the magneto circuit first and them check the ground circuit. If the engine will not shut off, check the ground circuit. Remember the engine is stopped by grounding the ignition coil through either the key switch or the start relay.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT TEST POINTS STX30 & STX38 (SN —210000) Black S2 PTO Switch 5 2 510 Yel Red G1 Battery 6 720 Purple 1 E1 Spark Plug 710 Purple 8 200 Red 3 720 Purple 7 100 Black S3 Neutral Start Switch 4 S1 Key Switch 9 710 Purple 714 Purple/ Black 500, 510 Yellow Late Model STX38 & STX46— S3 switch is labeled brake switch 715 12 Purple/ 714 Black 10 Purple/ Black K2 Start Relay Depiction may differ slightly from actual component 3/21/9
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT DIAGNOSIS STX30 & STX38 (SN —210000) Test Conditions: • Park brake engaged • Seat switch depressed • Transaxle in neutral • Meter negative (-) lead on engine ground • PTO switch disengaged • Meter positive (+) lead on numbered test point • Key switch in run position Test/Check Point Normal If Not Normal 13. Seat switch—yellow wire. Battery voltage Test 500 yel wire. 14. Seat switch—pink wire. Battery voltage Replace seat switch.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT TEST POINTS STX30 & STX38 (SN —210000) 19 22 S4 Seat Switch 13 500 Yellow 14 941 Wht 800 Pnk S1 Key Switch 21 22 100 Blk 15 85 30 16 18 23 87A K2 Start Relay Depiction may differ slightly from actual component 17 86 20 940 Wht X1 Engine Connector 3/21/97 4 - 39
CIRCUIT OPERATION AND DIAGNOSIS IGNITION CIRCUIT OPERATION STX38 (SN 210001— ) & STX46 Function: To create a spark that ignites the fuel/air mixture in the engine. Operating Conditions: To produce a spark, the key switch (S1) must be in the START or RUN position. The operator can be ON or OFF the seat—seat switch (S4); however, the PTO switch (S2) must be OFF and the brake switch (S3) must be ENGAGED (brake pedal applied) to start the engine.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch ST 200 Red B A 401 Yel G M 100 Blk Start Run 401 Yel Off S2 PTO Switch Y2 Fuel Shutoff Solenoid (Optional) 941 Wht 942 Wht (off) (0) F1 Fusible Link (1) 201 Org 941 Wht 942 Wht K1 Starter Solenoid S4 Seat Switch S3 Brake Switch (closed) (1) (off) (0) 946 Blk/Wht 110 Blk Red (0) (1) 945 Blk/Wht Seat Connector X1 Engine Connector 940 Wht 940 Wht G1 Battery Blk Coil 100 Blk A1 Ignition Module E1 Spark Plug 110 Blk W1
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 When diagnosing an ignition problem, isolate magneto circuit from ground circuit by separating engine connector. If engine will not start check magneto circuit first and then check ground circuit. If engine will not shut off, check ground circuit.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL IGNITION CIRCUIT TEST POINTS STX38 (SN 210001— ) & STX46 4 3 2 1 E1 Spark Plug 2 3 940 White Black 940 White X1 Engine Connector 4 1 4 3 2 940 White 110 Black 4 3 A1 Ignition Module 3 945 White/Black S4 Seat Switch 946 White/Black 946 3 White/Black S2 PTO Switch 4 2 940 White 941 White 942 White 4 S1 Key Switch 100 Black 4 4 2 2 2 945 3 White/Black 3 4 4 S3 Brake Switch 942 White 2 941 White 3/21/97 4 - 43
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CHARGING CIRCUIT OPERATION STX30 & STX38 (SN —210000) Function: To maintain battery voltage between 11.8 and 13.2. Operating Conditions: The key switch must be in the run position with the engine running for the charging system to operate. Theory of Operation: The charging system is a permanent magnet and stator design. Charging output is controlled by a regulatorrectifier (N1).
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL 210 Red N1 Regulator/ Rectifier Red 595 Brn/ Wht K1 Starter Solenoid Blk 590 Brn/ Yel U G Blk M G2 Stator M1 Starting Motor Red G1 Battery Blk W1 Frame Ground Ground Power SE3 - Charging Circuit 3/21/97 4 - 45
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CHARGING CIRCUIT DIAGNOSIS STX30 & STX38 (SN —210000) Test Conditions: • Park brake engaged • Engine running at fast idle • Transaxle in neutral • Meter negative (-) lead on battery negative (-) • Regulator/rectifier connector disconnected • Meter positive (+) lead on numbered test point • Key switch in run position Test/Check Point Normal If Not Normal 1. Battery positive terminal. 11.8—13.2 volts Test battery 2. Regulator/rectifier connector.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CHARGING CIRCUIT TEST POINTS STX30 & STX38 (SN G1 Battery —210000) 1 3 4 N1 Regulator/ rectifier 210 Red G2 Stator 2 2 3/21/97 595 Brn/ Wht 590 Brn/ Yel 4 - 47
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CHARGING CIRCUIT OPERATION STX38 (SN 210001— ) & STX46 Function: To maintain battery voltage between 11.8 and 13.2. Operating Conditions: The engine must be running for the charging system to operate. Theory of Operation: The charging system is of the permanent magnet and stator design. Charging output is controlled by regulator-rectifier (N1). The key switch (S1) must be in the RUN position and the engine running for the charging circuit to be fully operational.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch G M A B ST Start Run 200 Red Off F1 Fusible Link 201 Lt Org Red K1 Starter Solenoid 220 Red Red M M1 Starting Motor Blk N1 Regulator/Rectifier X1 Engine Connector U G1 Battery Wht Wht G G2 Stator Blk W1 Frame Ground Ground Power SE2- Charging 3/21/97 4 - 49
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CHARGING CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 Test Conditions: • Brake engaged • Engine running at fast idle • Regulator/rectifier connector disconnected • Meter negative (-) lead on battery negative (-) terminal • Key switch in run position • Meter positive (+) lead on numbered test point Test/Check Point Normal If Not Normal 1. Battery positive terminal . 11.8-13.2 volts Test battery 2. Regulator/rectifier connector (between white wires).
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL CIRCUIT OPERATION AND DIAGNOSIS CHARGING CIRCUIT TEST POINTS STX38 (SN 210001— ) & STX46 G1 Battery 1 White 2 3 Black 2 N1 Regulator/ rectifier White 3 Black G2 Stator 2 White 3 Black 220 4 Red 220 4 Red X1 Engine Connector K1 Starter Solenoid 3/21/97 4 - 51
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO CIRCUIT OPERATION STX30 & STX38 (SN —210000) Function: To provide power to energize the PTO clutch. Operating Conditions: The key switch must be in the run position and the PTO switch must be ON. Theory of Operation: The PTO circuit uses the ignition circuit to stop the engine if the operator gets off the seat with the PTO engaged.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch G M B A S2 S1 510 Yel 200 Red Start Run F1 Circuit Breaker Off S2 PTO Switch (off) (1) F1 Fusible Link (0) A B 201 Red E Red K1 Starter Solenoid 750 Blu Y1 PTO Clutch M M1 Starting Motor 120 Blk Red G1 Battery Blk W2 Engine Ground W1 Frame Ground Ground Power Control SE4 - PTO Circuit 3/21/97 4 - 53
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO CIRCUIT DIAGNOSIS POINTS STX30 & STX38 (SN —210000) Test Conditions: • Transaxle in neutral • Key switch in run position • Park brake engaged • Meter negative (-) lead on battery negative (-) terminal • PTO switch ON (engaged) • Meter positive (+) lead on numbered test point Test/Check Point Normal If Not Normal 1. Battery positive terminal. 11.8—13.2 volts Test battery 2. Key switch terminal B.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO CIRCUIT TEST POINTS STX30 & STX38 (SN 1 —210000) Red G1 Battery S2 PTO Switch 4 510 Yellow 2 S1 Key Switch 3 5 200 Red 750 Blue Terminal A—position will vary depending on key switch used 8 120 7 Black 750 6 Blue 3/21/97 Y2 PTO Clutch 4 - 55
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO AND HEADLIGHTS CIRCUITS OPERATION STX38 (SN 210001— ) & STX46 Function: To provide power to energize the PTO clutch and headlights (optional). Operating Conditions: PTO— The key switch (S1) must be in the RUN position, the seat switch must be DEPRESSED (operator ON the seat), the brake switch must be turned OFF (brake pedal released), and the PTO switch (S2) must be ENGAGED.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL S1 Key Switch E2 HeadLight (Optional) G M A Blk B S2 PTO Switch ST Start 200 Red (off) Run (1) Off (0) Red Blk 450 Yel/Wht 400 Yel Yel (Splice) F1 Fusible Link Blk S5 Headlight Switch 750 Blu (closed) 201 Org 120 Blk (0) (1) 451 Yel/Wht 125 Blk K1 Starter Solenoid Y1 PTO Clutch Red 125 Blk G1 Battery 120 Blk W2 Engine Ground Blk W1 Frame Ground Ground SE3 - PTO 3/21/97 Power Control SE5 - Headlights 4 - 57
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 NOTE: If there excessive vibration in PTO clutch area and noise coming from vibration between PTO clutch and pin—see page 4-53 step 5.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL PTO CIRCUIT TEST POINTS STX38 (SN 210001— ) & STX46 7 1 Black 750 5 Blue Red S2 PTO Switch G1 Battery 400 4 Yellow 200 Red 2 S1 Key Switch 2 K1 Starter Solenoid 200 Red 8 3 400 Yellow 125 7 Black 750 6 Blue 3/21/97 Y1 PTO Clutch 4 - 59
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL HEADLIGHTS CIRCUIT DIAGNOSIS STX38 (SN 210001— ) & STX46 Test Conditions: • Key switch in RUN position • Headlights switch ON (engaged) • Meter negative (-) lead on battery negative (-) terminal • Meter positive (+) lead on numbered test point NOTE: Fusible link (F1) 201 orange wire is designed to melt internally.
CIRCUIT OPERATION AND DIAGNOSIS ELECTRICAL HEADLIGHTS CIRCUIT TEST POINTS STX38 (SN 210001— ) & STX46 9 Black 200 Red 2 W1 1 K1 Starter Solenoid Red G1 Battery 2 S1 Key Switch 3 200 Red S2 PTO Switch 400 4 Yellow 400 Yellow 450 5 Yellow/White 451 Yellow/White 6 8 Red S5 Headlight Switch 8 5 450 Yellow/White Red E2 Headlights Headlights Kit Harness 9 Black W2 451 6 Yellow/White 9 120 Black Yellow 7 Headlights Kit Harness 9 Black 3/21/97 4 - 61
TESTS AND ADJUSTMENTS ELECTRICAL TESTS AND ADJUSTMENTS GROUND CIRCUIT TESTS Reason: To check for opens, loose terminal wire crimps, poor connections, or corrosion in the ground circuit. The voltmeter method checks ground connections under load. Equipment: • Ohmmeter or voltmeter GROUND M55642 W1—Frame Ground 3. Put meter red lead on ground terminal of circuit or component to be tested that is closest to the battery negative terminal.
TESTS AND ADJUSTMENTS ELECTRICAL BATTERY TEST Results: Reason: To check condition of battery and determine battery voltage. Equipment: • Hydrometer • Voltmeter or JTO5685 Battery Tester • Battery voltage less than 12.4 VDC, charge battery. • Battery voltage more than 12.4 VDC, test specific gravity. • All cells less than 1.175, charge battery at 10 amp rate. • All cells less than 1.225 with less than 50 point variation, charge battery at 10 amp rate. • All cells more than 1.
TESTS AND ADJUSTMENTS 3. Check if battery is accepting a 10 amp charge after 10 minutes at boost setting. Battery will not accept 10 amp charge after 10 minutes at boost setting: replace battery. Battery is accepting 10 amp charge after 10 minutes at boost setting, and battery did not need water: go to steps 6 and 7. Battery is accepting 10 amp charge after 10 minutes at boost setting, but battery did need water or all cells were below 1.175: go to steps 4 and 5. 4. Set charger at 15—25 amps.
TESTS AND ADJUSTMENTS ELECTRICAL REGULATED VOLTAGE OUTPUT TEST UNREGULATED VOLTAGE OUTPUT TEST Reason: Reason: To determine regulated voltage output of the regulator/ rectifier. To measure stator voltage output to determine stator condition. Equipment: Equipment: • Voltmeter • Voltmeter A M55942 Connections: 1. Remove surface charge from battery by cranking engine for 15 seconds. 2. Connect meter red lead to positive battery terminal. 3. Connect meter black lead to negative battery terminal.
TESTS AND ADJUSTMENTS ELECTRICAL STARTER SOLENOID TEST STARTER AMP DRAW TEST Reason: Reason: To determine if starter solenoid or starter is defective. To determine the amperage required to crank the engine and check starter motor operation under load. IMPORTANT: STX38 Serial Numbers (STXH270001—277450) (STXJ270001—275010) (STXH270001— )—If the starter pinion fails to disengage from flywheel the steel and nylon washers in the bendix of the starter are reversed.
TESTS AND ADJUSTMENTS ELECTRICAL IGNITION SPARK TEST IGNITION MODULE AIR GAP ADJUSTMENT Reason: Reason: To determine condition of ignition system. To adjust the air gap between the ignition module and the flywheel to a specific dimension needed for proper ignition timing. Equipment: • D-05351ST Spark Tester Equipment: • 0.25 mm (0.010 in.) feeler gauge B A E C D A M55937 Connections: 1. Remove ignition module high tension lead (B) from spark plug (A). 2.
TESTS AND ADJUSTMENTS ELECTRICAL IGNITION MODULE TEST SEAT SWITCH TEST Reason: Reason: To determine condition of ignition module windings. To ensure proper operation of seat switch. Equipment: Equipment: • Ohmmeter • Ohmmeter Procedure: 1. Park machine on level surface and turn key switch OFF. 2. Shift lever in NEUTRAL and park brake LOCKED. 3. Disconnect harness connector from seat switch. A C B M55638 Procedure: 1. Put transaxle in neutral. Put key switch in off position. 2.
TESTS AND ADJUSTMENTS ELECTRICAL BRAKE PEDAL/PARK BRAKE SWITCH TESTS BRAKE SWITCH ADJUSTMENT Reason: Reason: To make sure the brake pedal switch operates properly. To ensure proper that engine starts only when brake fully applied. Procedure: Equipment: 1. Depress brake pedal and set park brake. • Ohmmeter A Procedure: 1. Park machine on level surface and turn key switch OFF. 2. Shift lever in NEUTRAL and park brake LOCKED. 3. Disconnect harness connector from brake switch.
TESTS AND ADJUSTMENTS ELECTRICAL HEADLIGHT SWITCH TEST (OPTIONAL) KEY SWITCH TESTS Reason: Reason: To verify key switch functions are operating properly. To make sure the headlight switch terminals have continuity when the headlight switch is ON. Equipment: • Ohmmeter or Continuity Tester Equipment: • Ohmmeter or Continuity Tester Procedure: Procedure: 1. Park machine on level surface and turn key switch OFF. 2. Shift lever in NEUTRAL and park brake LOCKED. 3.
TESTS AND ADJUSTMENTS ELECTRICAL PTO SWITCH TESTS PTO CLUTCH TEST IMPORTANT: PTO switch can fail from prolonged exposure to moisture. Original switch has seven terminals not six. The extra terminal is not needed for STX application. Reason: To check operation of PTO clutch coil. Equipment: Reason: To make sure terminal continuity is correct in the ON and OFF positions. • Jumper Wire • Ohmmeter Equipment: • Ohmmeter or Continuity Tester A M55948 Connections: A B 1. Put transaxle in neutral. 2.
TESTS AND ADJUSTMENTS ELECTRICAL PTO CLUTCH AIR GAP STX30 & STX38 (SN —210000) FLYWHEEL MAGNETS Reason: Reason: To set the PTO clutch air gap at a specific dimension for proper operation. To make sure flywheel magnet(s) have enough force to induce current in ignition coil and stator. Equipment: • Screwdriver Procedure: 1. Put transaxle in neutral. 2. Put key switch and PTO switch in off position. 3. Engage park brake. A Procedure: 1. Park machine on level surface and turn key switch OFF. 2.
TESTS AND ADJUSTMENTS ELECTRICAL TRANSMISSION NEUTRAL SWITCH STX30 & STX38 ( —210000) Reason: To make sure tractor cannot be started while in gear. Procedure: 1. Remove spark plug wire and raise rear tire. A M42194 2. Attempt to start engine while moving gear shift lever towards reverse or forward gear. If wheels rotate during cranking, readjust neutral switch by turning switch out slightly. 3. Connect spark plug wire.
REPAIR ELECTRICAL REPAIR REMOVE AND INSTALL SEAT SWITCH REMOVE AND INSTALL KEY SWITCH AND PTO SWITCH NOTE: Seat switch connector has an internal spring which will short cavities of connector together when it is disconnected from seat switch. This prevents operator from defeating seat switch by leaving connector disconnected. B A B A M55806 M55846 1. Remove retaining screws (A) and Bracket (B). C 1. Tilt seat forward. 2. Disconnect connector (A). 3.
REPAIR ELECTRICAL REMOVE AND INSTALL STARTER SOLENOID F E E NOTE: Relay in located at the right-hand front corner of battery compartment. F G I A H G J M58361 M55914 1. Remove battery. 2. Disconnect all wires and remove solenoid. NOTE: When installing connectors to solenoid, make sure both barrel terminals (A) are pushed allthe-way on so they stay locked onto their stud. 5. Remove two white stator wires from connector (F). 6. Remove clamps (G). 7. Remove cap screws and stator (E). 8.
REPAIR ELECTRICAL 16. Install and tighten cap screws to specification. 17. Remove feeler gauge and connect wire (D) to terminal. A Specifications: Ignition Module Air Gap . . . . . . . . 0.25mm (0.01 in.) Ignition Module Cap Screws . . . . . . . . . . . . . . . . . . . . . 4.0—6.2 N•m (35–55 lb-in.) Stator Cap Screws . . . . . . . . . . . . . . 4 N•m (35 lb-in.) Flywheel Cap Screw . . . . . . . . . . . .
REPAIR ELECTRICAL REMOVE AND INSTALL STARTER REPAIR STARTER AND REPLACE BRUSHES B A A M55921 B M55854 NOTE: Some starters may have a relay located at the right-hand rear corner of battery compartment. When installing connector to relay, make sure all barrel terminals stay locked on connector stud. 1. Disconnect negative battery cable. 2. Disconnect starter cable (B) from starter. 3. Remove starter cap screws (A) and starter. 4. Install starter and cap screws to specification. 5.
REPAIR ELECTRICAL D F E M55917 4. Clean stud terminal (F), replace if threads are stripped or if it is corroded. 5. Replace insulator (E) if cracked. 6. Clean positive brushes (D )contact point with end cap. Using Ohmmeter, check for no continuity between positive brushes (D) and end cap, and also between stud terminal (F) and end cap. Replace positive brushes (D) if continuity is indicated. G M46892 3. Rotate armature on growler while holding a steel strip (e.g. hacksaw blade) on armature.
REPAIR ELECTRICAL REMOVE AND INSTALL TRANSMISSION NEUTRAL SWITCH STX30 & STX38 (SN —210000) c CAUTION If neutral switch (B) on Late Model transmissions is turned down too far, vehicle could start in partial gear. Perform neutral switch adjustment. 5. With transmission in neutral, turn switch down until switch just shows continuity between the two terminals. (Use ohmmeter or continuity light). Turn switch down an additional 1/4 minimum to 3/4 maximum turn until switch terminals line up with wire lead.
REPAIR ELECTRICAL NOTES 4 - 80 3/21/97
CONTENTS POWER TRAIN CONTENTS Page POWER TRAIN SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GENERAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 REPAIR SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 TORQUE SPECIFICATIONS (ALPHABETICAL ORDER) . . . . . . . . . . . . . . . . . . . . . 6 ENGINE OUTPUT SHAFT LUBRICATION SPECIFICATIONS . .
CONTENTS POWER TRAIN TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 TESTS AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 CLUTCH/BRAKE PEDAL LINKAGE AND TRACTION DRIVE SYSTEM . . . . . . . . . 34 BRAKE SPRING ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 BRAKE PAD ADJUSTMENT.
POWER TRAIN SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Dimensions: Overall Axle Width (end-to-end). . . . . . . . . . . . . . . . . . . . . . . . 735.432 mm (28.954 in.) Overall Case Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432.562 mm (17.030 in.) Overall Case Length (front-to-rear) . . . . . . . . . . . . . . . . . . . . . 272.034 mm (10.710 in.) Overall Height (top of input shaft-to-bottom case) . . . . . . . . . . . 183.400 mm (7.220 in.
SPECIFICATIONS Gear Teeth—STX38 (SN 210001— POWER TRAIN ) & STX46: Bevel Pinion Gear (input shaft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Bevel Pinion Gear (input shaft) STX38 (SN 301383— ) . . . . . . . . . . . . . . . . . . . . . 12 Drive Shaft: Bevel Drive Gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Bevel Drive Gear STX38 (SN 301383— ) . . . . . . . . . . . . . . . . . . . . . . . . . . .
POWER TRAIN SPECIFICATIONS REPAIR SPECIFICATIONS Wear Tolerances: Input Shaft— Shim: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.63x1.0x0.01—0.082 in. Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Visual Check Washers: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.63x1.4x0.046 in. Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS POWER TRAIN Wear Tolerances—continued: Differential Assembly— Bevel Gear Cross Shaft: Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Visual Check Right Axle Shaft— Shims: Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.76x1.12—1.25x0.01—0.06 in. Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
POWER TRAIN SPECIFICATIONS OTHER MATERIALS Input Shaft Needle Bearings Grease . . . . . . . . . . . . . . . . . . . . . . . . Unirex® N3 Grease Transaxle Housing Grease . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shell Darina® D Grease Transaxle Sealant— . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS POWER TRAIN NOTES 5-8 3/21/97
COMPONENT LOCATION POWER TRAIN COMPONENT LOCATION TRANSAXLE—PEERLESS MODEL 920-017 STX30 (SN —135158) (SN 160759— ) STX38 (SN —139614) (SN 185587—210000) Nut Needle Bearing Rod Shaft Key Sheave Thrust Washer Set Screw Seal Snap Ring Switch O-Ring Spring Bushing Shaft Disk Ball Thrust Washer Gear Bushing Key Washer Shift Collar Thrust Washer Shaft Pinion Key Shaft Pinion Chain Snap Ring Washer Sprocket Spacer Bushing Link Chain Thrust Washer Drive Spacer Sprocket Washer Shaft Gear Gear Chock
COMPONENT LOCATION POWER TRAIN TRANSAXLE—PEERLESS MODEL 930-004 & 930-004A STX30 (SN —135158) (SN 160759— ) STX38 (SN —139614) (SN 185587—210000) Nut Sheave Thrust Washer Set Screw Screw Needle Bearing Thrust Washer Gear Bushing Shift Collar Shaft Pinion Shaft Key Washer Thrust Washer Snap Ring Pinion Key Chain Sprocket Spacer Snap Ring Washer Washer Bushing Link Chain Gear Axle Seal O-Ring Shaft Bushing Disk Washer Grease Spring Shaft Fitting Key (2 Used) Ball Needle Bearing Rod Snap
COMPONENT LOCATION POWER TRAIN TRANSAXLE—PEERLESS MODEL 915-012A & 915-012B STX30 (SN 135159—160758) STX38 (SN 139615—185586) Lock Nut Ball Sheave Needle Bearing Shifter Rod Spring Grease Fitting Shaft Key Thrust Washer Thrust Washer Seal Shaft Needle Shaft Bearing Key Washer Snap Ring Screw Washer Thrust Washer Bevel Gear Snap Ring Shift Collar Shaft Key Shaft Countershaft Screw Reverse Idler Spacer Spacer Snap Ring Thrust Washer Spur Gear Washer Spacer Seal Shaft Screw Flange Nut C
COMPONENT LOCATION POWER TRAIN TRANSAXLE—DANA 5-SPEED STX38 (SN 210001—301382) STX46 1. Flange bearing 2. Shim (0.632x1.00x0.010–0.082 in.) 3. Spur gear (14 teeth) 4. Shift collar 5. Shift key (4 used) 6. Shifter Fork 7. Intermediate shifter/brake shaft 8. Woodruff key 9. Upper case housing 10. O-ring seal (2 used) 11. Screw (2 used) (1/4x0.734–20 in.) 12. Detent ball (2 used) 13. Detent spring (2 used) 14. Set screw (2 used) Flush Only 15. Shifter shaft rubber boot 16. Screw (14 used) (1/4x0.734–20 in.
COMPONENT LOCATION POWER TRAIN 1 2 9 –10 N•m (100–125 lb-in.) 4 11 12 15 6 9 –10 N•m (100–125 lb-in.) 10 5 Flush Only 14 13 3 9 16 7 8 18 19 20 17 21 29 22 30 23 31 24 38 39 32 25 40 26 41 33 27 28 42 43 34 44 58 36 35 45 46 37 47 48 59 49 60 50 61 51 62 52 64 63 53 65 54 55 Shims (42 and 48) are critical when any gears or case halves are being replaced. 56 66 67 57 68 69 72 70 74 73 71 75 76 78 77 79 80 81 85 86 3/21/97 83 18 – 22.
COMPONENT LOCATION POWER TRAIN TRANSAXLE—DANA 5-SPEED STX38 (SN 301383— ) 1. Flange bearing 2. Shim 3. Spur gear (12 teeth) 4. Shift collar 5. Shift key (4 used) 6. Intermediate shifter/brake shaft 7. Woodruff 8. Upper case housing 9. Screw (16 used) 10. Detent ball (2 used) 11. Detent spring (2 used) 12. Detent cover 13. Detent cover screw 14. V-ring 15. Shifter fork 16. Retaining ring 17. Drive chain large sprocket/reverse gear (18 teeth) 18. Spacer 19. Intermediate shaft 1st gear (37 teeth) 20.
COMPONENT LOCATION POWER TRAIN 2 13 12 4 11 5 1 9 –10 N•m (100–125 lb-in.) 3 14 10 9 6 9 7 17 19 20 16 18 21 22 28 23 38 37 29 15 24 30 26 39 31 27 25 40 32 41 35 33 42 56 57 44 45 34 46 43 58 36 47 48 59 60 49 50 61 51 62 52 53 Shims (42 and 48) are critical when any gears or case halves are being replaced. 63 55 64 54 69 65 71 70 66 67 68 73 74 75 76 79 72 81 82 77 78 80 82 3/21/97 18 – 22.6 N•m (160–200 lb-in.
COMPONENT LOCATION POWER TRAIN TRACTION DRIVE SYSTEM STX30 & STX38 (SN Bolt —210000) Shaft Key Spacer Sheave Bolt Extension Spring Hub Guide Flange Nut Bolt Washer Screw Flange Nut Clamp Belt Bolt Flange Nut Link Compression Spring Idler Bushing Idler Washer Link Link Cap Link Cap Screw Washer Nut Flange Nut Cap Guide Guide Guard Flange Nut Flange Nut Flange Nut Flange Nut Guard M85808 5 - 16 3/21/97
COMPONENT LOCATION POWER TRAIN CLUTCH AND BRAKE PEDAL STX30 & STX38 (SN —210000) Cotter Pin Washer Pad Compression Spring Strap Pad Lever Washer Washer Flange Nut Pedal Cotter Pin Rod Extension Spring Shaft Snap Ring Washer Extension Spring Knob Washer Screw Stud Lock Nut Cotter Pin Knob Clip Rod Flange Nut Extension Spring Rod Extension Spring Cotter Pin Lock Nut Screw Bearing Bearing Lock Nut Ball Joint Cap Screw Washer Arm Washer Lock Nut Seal M85810 3/21/97 5 - 17
COMPONENT LOCATION POWER TRAIN TRACTION DRIVE SYSTEM STX38 (SN 210001— ) & STX46 1. Frame weldment—idler adjustment 2. Carriage bolt (M8x45) 3. Clutch bellcrank bracket 4. Bushing 5. Cap screw 6. Clutch assist spring assembly 7. Carriage bolt (M8x45) 8. Clutch cross shaft 9. Park lever 10. Idler 11. Carriage bolt (M8x50) 12. Clutch spring 13. Washer (2 used) (11/32x7/8x1/16 in.) 14. Belt guide 15. Flange nut (M8) 16. Crankshaft drive sheave 17. Foot pad 18. Cap screw (M8x35) 19. Bellcrank 20.
COMPONENT LOCATION POWER TRAIN TRACTION DRIVE SYSTEM 12 14 13 8 6 15 11 16 10 17 9 7 2 18 3 19 4 5 1 20 26 25 21 27 28 29 50 35 33 36 22 30 32 31 23 24 37 38 40 49 41 34 39 47 42 48 43 44 46 45 M55827 SHIFT LINKAGE SYSTEM 52 51 57 53 66 55 65 54 58 56 59 64 63 62 61 60 M55836 3/21/97 5 - 19
THEORY OF OPERATION POWER TRAIN THEORY OF OPERATION CLUTCH PEDAL AND BELT TRACTION DRIVE SYSTEM OPERATION STX30 & STX38 (SN —210000) Function: Theory of Operation: The function of this system is to transfer power from the engine to the transaxle. This system also allows the power transfer to be interrupted in order to stop in gear, change to a different gear or direction, engage power again, or shift to neutral and push the unit with the engine on or off.
THEORY OF OPERATION POWER TRAIN CLUTCH PEDAL AND BELT TRACTION DRIVE SYSTEM OPERATION STX38 (SN 210001— ) & STX46 Theory of Operation: B A C Function: The function of this system is to transfer power from the engine to the 5-speed transaxle. This system also allows the power transfer to be interrupted in order to stop in gear, change to a different gear or direction, engage power again, or shift to neutral and push the unit with the engine on or off.
THEORY OF OPERATION POWER TRAIN TRANSAXLE OPERATION PEERLESS MODEL 920-017, 930-004 & 930-004A STX30 (SN —135158) (SN 160759— ) & STX38 (SN —139614) (SN 185587—210000) Theory of Operation: Forward: Function: The transaxle transmits power from the engine, through the belt traction drive system, into the transaxle gear matrix, and out the drive axles to the rear wheels. The transaxle provides a gear selection of five forward speeds and one reverse speed.
THEORY OF OPERATION POWER TRAIN TRANSAXLE OPERATION PEERLESS MODELS 915-012A/915-012B STX30 (SN 135159—160758) & STX38 (SN 139615—185586) Theory of Operation: Forward: The transaxle input sheave is keyed to the input pinion (F). The input pinion (F) drives the bevel input gear (H). The bevel input gear (H) rotates independently of the shifter/brake shaft (A) but constantly rotates the drive shaft (K) and gears (J).
THEORY OF OPERATION POWER TRAIN TRANSAXLE OPERATION STX38 (SN 210001— ) & STX46 Function: C The transaxle transmits power from the engine, through the belt traction drive system, into the transaxle gear matrix, and out the drive axles to the rear wheels. The transaxle provides a gear selection of five forward speeds and one reverse speed. Q D O It also provides the means to interrupt the flow of power when shifted into neutral.
THEORY OF OPERATION POWER TRAIN R S T U M42318 Reverse: As in forward—likewise in reverse, with engine running and clutch engaged, the transaxle input sheave turns rapidly in a clockwise direction. Power is transferred through the belt drive sheave into the input shaft pinion gear (C).
THEORY OF OPERATION POWER TRAIN BRAKE SYSTEM COMPONENT LOCATION AND OPERATION IMPORTANT: Early Model STX30 & STX38 (SN —210000) brake linkage differs slightly. Theory of Operation remains the same. Function: The brake system allows the operator to slow down, stop, or lock the tractor into park position.
THEORY OF OPERATION POWER TRAIN A B H C F G D M K L E J F I M42594 G M42586 N O P Q M55833 3/21/97 5 - 27
TROUBLESHOOTING POWER TRAIN ● ● ● Belt worn, frayed, glazed, or stretched—replace belt ● ● ● ● ● Clutch/brake pedal linkage out of adjustment—adjust properly ● ● ● ● Clutch/brake components worn, bent, or broken— replace and adjust properly ● ● ● ● Shift lever and linkage bent, worn, out of adjustment, or broken—replace or adjust properly Input sheave, input shaft, and axle keys or keyways worn or damaged—replace ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●
POWER TRAIN TROUBLESHOOTING NOTES 3/21/97 5 - 29
DIAGNOSIS POWER TRAIN DIAGNOSIS Test Conditions: • Tractor on level surface • Front wheels blocked • Engine OFF • Rear wheels raised off surface with axle housings on jack stands Test/Check Point Normal If Not Normal 1. Drive belt. Belt in good condition, not glazed, split, unraveled, or stretched. Minimum width 11 mm (0.43 in.). Replace drive belt. 2. Sheaves, idlers, and belt guides. Sheaves, idlers and guides in good condition. Guides installed, properly adjusted and tight.
DIAGNOSIS POWER TRAIN 1 2 3 M55827 4 M55836 7 5 8 6 M42312 3/21/97 M55832 5 - 31
DIAGNOSIS POWER TRAIN Test Conditions: • Tractor operating in test area • Tests run at engine slow idle and fast idle • Engine at operating temperature • Transaxle run through all speeds in both directions Test/Check Point 1. Running in test area. Normal If Not Normal Engine running smoothly through out throttle range. Adjust or tune engine. Belt not squealing or vibrating. Check belt condition. Check adjustment and condition of idlers and guides. Replace components as needed.
DIAGNOSIS POWER TRAIN 1 M55827 1 M55836 1 M42312 3/21/97 M55832 5 - 33
TESTS AND ADJUSTMENTS POWER TRAIN TESTS AND ADJUSTMENTS CLUTCH/BRAKE PEDAL LINKAGE AND TRACTION DRIVE SYSTEM Reason: To ensure clutch/brake pedal linkage and traction drive system maintains traction in all three lower gears up a 17° slope. Also, to ensure it disengages traction drive belt, engages brake to slow down or stop tractor within a specified distance, and holds tractor stationary in PARK position on a 17° slope or less.
TESTS AND ADJUSTMENTS POWER TRAIN 8. Once above measurement is obtained, recycle clutch/brake pedal again. 9. Remeasure distance, it should be the same. This brake setting should hold the tractor stationary on a 17° slope. If distance is greater than 8 mm (0.32 in.)— B A 10. With park brake set, gradually loosen lock nut (E) until distance of 7.5—8 mm (0.30—0.32 in.) is obtained. 11. Recycle park brake a few times and remeasure distance each time (see Step 7).
TESTS AND ADJUSTMENTS POWER TRAIN CLUTCH SPRING ADJUSTMENT IMPORTANT: Anytime the brake or clutch spring need to be adjusted, both must be examined to ensure desired results will be obtained. 2. If brake components were not replaced, drive tractor in a safe, open, and level area at fast idle in high gear. Apply a “panic stop” force (no more than 50 pounds of force) to brake pedal—tractor must stop at rate of 30.5 cm (12 in.) per mph. A B F G M42597 H I M42579 1.
TESTS AND ADJUSTMENTS POWER TRAIN SHIFT LINKAGE ADJUSTMENT F Reason: To ensure shift lever obtains all shift positions and that neutral position does not allow transaxle to creep. G E Conditions: • Safely raise rear wheels 51 mm (2 in.) off surface and block front wheels (front and rear). • Shift lever in neutral. • Park brake off. Procedure: M42535 5.
REPAIR POWER TRAIN REPAIR Rotor BRAKES STX30 & STX38 (SN —210000) REMOVAL/ INSTALLATION Pin Brake Pedal Brake Pads Lock Nut Pin Set Compression Spring Cap Screw (2 Used) Return Spring M51988 3. Remove cap screws, rotor, and brake pads. 4. Check brake linkage, pads and rotor for wear, binding and dirt. Transaxle Brake Rotor Brake Lever Shifter/Brake Shaft Installation 5. Apply LUBRIPLATE® to pins. 6. Install pads.
REPAIR POWER TRAIN TRACTION DRIVE BELT REMOVAL/ INSPECTION/INSTALLATION— STX30 & STX38 (SN —210000) A Removal 1. Remove ignition key and disconnect spark plug wire. C B NOTE: It is not necessary to remove PTO clutch to remove drive belt on units with the spun formed drive sheave. M51976 C 7. Remove sheave (A), belt from guide (B) and idler (C). B B B A A M52005 2. Remove PTO clutch (A). 3. Disconnect rods (B) from arm (C). M52007 8. Remove belt from sheave (A).
REPAIR POWER TRAIN A E C B B A M51976 3. Install belt on guide (B) and idler (C). F NOTE: Apply NEVER-SEEZ® lubricant to crankshaft before installing sheave. D 4. Install sheave (A). C C M52006 B B A M52005 5. Install spacer and PTO clutch (A). 6. Connect rods (B) to arm (C). 5 - 40 7. Install lever (D) spring (C). 8. Engage park brake. 9. Slide sheave (E) to rear until belt slack is removed. Tighten sheave. 10. Release park brake.
REPAIR POWER TRAIN CLUTCH ARM REMOVAL/ INSTALLATION— STX30 & STX38 (SN —210000) TRANSAXLE—REMOVAL/ INSTALLATION STX30 (SN —135158) (SN 160759— ) & STX38 (SN —139614) (SN 185587—210000) Removal 1. Engage park brake. C A D IMPORTANT: Several versions of Peerless Model Transaxles were used. 920-017 Model does not have grease fittings at the end of the axle housings. The 930-004 and 930-004A models have grease fittings at the end of the axle housing. E B 1.
REPAIR POWER TRAIN B B C C D D M85844 10. Disconnect linkage (C), unplug neutral start switch (D) and remove cap screw (B) from left side of transaxle. M85844 3. Connect linkage (C) on left side of transaxle. 4. Install cap screw (B). 5. Connect neutral start switch (D). Specifications: Transaxle Mounting Cap Screws to Hanger Bracket (Front) . . . . . . . . . . . . 15 N•m (132 lb-in.) 6. Push belt through transaxle guide (not depicted). 7. Install belt on transaxle sheave (not depicted).
REPAIR POWER TRAIN TRANSAXLE CASE—DISASSEMBLY STX30 (SN —135158) (SN 160759— ) & STX38 (SN —139614) (SN 185587—210000) D A B E C PEERLESS MODEL 920-017, 930-004, & 930-004A NOTE: Model 930 transaxles only—Peerless made a change in the transmission case pocket which holds the differential gears. It is now possible that a tolerance stackup could result in the upper case forcing the ends of the axles against the spider gear pin. This would cause the axles to turn hard or even lock them up.
REPAIR POWER TRAIN Counter Shaft—Disassemble 1. Remove shifter fork from brake shaft assembly. 2. Remove brake shaft and counter shaft assemblies. . C B I E A G B D L J A M F N H P K R E K O Q M52018 3. Remove bushing (A), washer (B), and output gear (C) from pinion (D). 4. Remove pinion (D), washer (B), and bushing (A). 5. Remove bushing (E), washer (F), and spacer (G) from shaft (J). 6. Pull ends of counter and brake shafts together and remove chain (I). F 7. Remove 9 tooth gear (H). 8.
REPAIR POWER TRAIN Differential—Disassemble 1. Remove differential assembly from lower case. G C A B F I D E H E D G J I A C M52019 2. Remove blocks (G). 3. Remove axle (B) assembly. 4. Remove axle (J) assembly. 5. Remove seals (A) from axles. 6. Remove retainers (E), gear (D), and washer (C) from axles. 7. Remove pin (H) and gears (I) from gear (F).
REPAIR POWER TRAIN Brake Shaft—Assemble A C H B G I D L E K F M H N O J Q L C P M52021 1. Put LUBRIPLATE lubricant in keyways of shaft (G). 2. Position keys (H) near end of shaft in keyways. Install collar (F) over keys with thicker shoulder of collar towards shaft. 3. Install gear (E—15 teeth) with thicker shoulder towards collar (F). NOTE: Grease ends bushings. of shaft before 5. Install sprocket (I) and spacers (J). 6.
REPAIR POWER TRAIN Input Shaft—Assemble Case—Assemble A 1. Fill case with John Deere Moly High Temperature EP Grease. Transaxle capacity is 1.0 L (30 oz). B D A B E C C M52015 D E F G H I 2. Apply silicone sealant and install top cover. Torque cap screws (E) to 11.3 N•m (100 lb-in.). 3. Install ball (C), spring (B), and set screw (A). Tighten screw one turn below flush with cover. 4. Install seal (D). 5. Turn input shaft to check for binding. M52016 1.
REPAIR POWER TRAIN TRANSAXLE—REMOVAL/ INSTALLATION STX30 (SN 135159—160758) & STX38 (SN 139615—185586) Installation 1. Install transaxle leaving hardware loose. 2. Install drive belt. (PEERLESS MODELS 915-012A & 915-012B) D E IMPORTANT: Early models used several versions of transaxle. The 915 model is used in the 1992 production models and has a completely different shape then the older models. M85844 Removal 1. Remove ignition key and disconnect spark plug wire. 2.
REPAIR POWER TRAIN TRANSAXLE CASE—DISASSEMBLY STX30 (SN 135159—160758) & STX38 (SN 139615—185586) A B C D C F H D G G E F M56074 E A NOTE: Note position of parts for reassembly. Lay parts out in a systematic order to aid assembly. Check all gears for wear, replacing mating gears as a set. B M42177 NOTE: When separating transaxle cover, detent ball and spring may fall out. Reverse idler shaft may also drop. Work cover up evenly over shifter fork. 4.
REPAIR POWER TRAIN Differential M N B O E Q D C A R P F M54613 1. Remove snap rings (C), thrust washers (A) and bevel side gears (B). 2. Remove pinion gears (D) from pinion shaft (E). M56076 Shift Shaft K F M I R—Shift Keys 1. Face undercut side of gears toward bevel gear. 2. Face detent cone washers toward shaft keys. 3. Face differential input gear with undercut side towards bevel gear. 4. Face undercut I. D. of shift collar towards bevel gear.
REPAIR POWER TRAIN Counter Shaft Shift Lever and Detent B NOTE: The shaft bushing area is longer on one end. Note the direction in which the shaft was removed and the relationship of the gears to the shaft. The thick washer and longer shaft end should be install toward the brakes. D C B A B A M42183 F C M42182 1. Inspect gear teeth (C, D, F) and splines and shaft splines for damage. Note the position of the thin (A) and thick (B) washers. 1. Check tabs (B) for wear.
REPAIR POWER TRAIN REPAIR TRANSAXLE CASE—ASSEMBLY STX30 (SN 135159—160758) & STX38 (SN 139615—185586) D C F G B B A C C E A B G E H F I D M56078 NOTE: Do NOT put grease between slinger and case. 1. Apply approximately 532 mL (18 oz.) of EP90 Lithium Grease (John Deere Moly, High Temperature EP Grease) to all transaxle components and wear areas. 2. Fill both cavities (C). 3. Apply a small bead of flexible sealant around case sealing surface. NOTE: Make sure seals (B) are in place on axle.
REPAIR POWER TRAIN TRACTION DRIVE BELT REMOVAL/ INSPECTION/INSTALLATION— STX38 & STX46 LATE MODEL NOTE: If drive belt is in good condition, it doesn’t to be completely removed to take out the transaxle. Just lock the park brake to disengage it from the transaxle drive sheave. Removal: 1. Park tractor on level surface. 2. Remove mower deck. 3. Safely raise and block tractor to gain easy access to underside of frame. C Inspection: 1.
REPAIR POWER TRAIN F G I E J D G D M42771 C 3. Coat engine output shaft (G) and inside surface of traction drive sheave (I) with John Deere NeverSeez® before installing drive sheave. (Hint: hold sheave in place by seating drive belt in sheave groove.) 4. Install front idler (J). (Hint: hold idler in place by seating drive belt in sheave groove.) M42769 2.
REPAIR POWER TRAIN TRACTION DRIVE SYSTEM REMOVAL/INSPECTION/ INSTALLATION— STX38 (SN 210001— ) & STX46 A–Bellcrank Spring B–Tension Spring C–Park Latch D–Front Idler E–Belt Guide #1 F–Crankshaft Drive Sheave Removal/Inspection/Installation: 1. Remove mower deck. 2. Use this drawing for complete repair of system 3. Install mower deck.
REPAIR POWER TRAIN SHIFT LINKAGE REMOVAL/INSTALLATION STX38 (SN 210001— ) & STX46 B A C 13.5—17.6 N•m (120—156 lb-in.) G P D O 10.8—16.3 N•m (96—144 lb-in.) E F N M 10.8—16.3 N•m (96—144 lb-in.) L K H I J 10.8—16.3 N•m (96—144 lb-in.) M55830 1. Remove battery. 2. Block rear of tractor off surface so you can remove left drive wheel. 3. Remove shift knob (G). 4. Remove lock nuts (M and O) to remove shift link (N). 5. Remove lock nuts (A and I) and cap screws (B and F). 6.
REPAIR POWER TRAIN TRANSAXLE—REMOVAL/ INSTALLATION STX38 (SN 210001— ) & STX46 IMPORTANT: STX38 (SN 301383— ) transaxle differs slightly from STX38 (SN 210001—301382) and STX46 transaxle. 1. Raise and block tractor off surface. 2. Remove drive wheels. A B 8. Remove front cap screws (F) and rear hardware (G). 9. Carefully remove transaxle to workbench. 10. Install transaxle in reverse order of removal. 11. Tighten mounting hardware. Front Hanger cap screws to frame . . . . . . . . . . . . . . . . . . .
REPAIR POWER TRAIN Remove Shifter Detent Assembly Remove Brake Assembly: STX38 (SN 210001—301382) and STX46 Transaxle D E G F 2 M42316 1. Remove shifter shaft rubber boot (E). 2. Remove both set screws (D) and detent springs (G). STX38 (SN 301383— ) Transaxle 1 Contact Points M58279 IMPORTANT: First check brake components for wear. Check for brake disc contacting the case (1) and/or brake lever contacting its mounting bracket (2), top or bottom. If so, all three components must be replaced.
REPAIR POWER TRAIN Separate Transaxle Housing Case Halves: B Inspect Input Shaft/Pinion Gear Assembly: A A B C M42312 1. Remove all sixteen transaxle housing socket head screws (B)—brake assembly (A) should be removed already, see previous procedure. D E M42525 Lower Case Half Upper Case Half 1. Visually check overall condition of assembly, including the key and keyway, and the drive sheave hub keyway as well. 2. Check condition of pinion gear (D)—look for wear, pitting, broken teeth, etc. 3.
REPAIR POWER TRAIN Disassemble Input Shaft/Pinion Gear Assembly: B A C 6. If measurement results in a “NO GO” reading for either bearing, replace both bearings (ordered as set with special grease) by carefully pressing them from case half bore without damaging bore. 7. Clean and inspect bore. If scratched or deformed, replace upper case half. Disassemble Shifter Shaft Assembly: D E M42320 B A 1.
REPAIR POWER TRAIN Inspect Idler Combination Gear Assembly: STX38 (SN 210001—301382) and STX46 Transaxle E B C F G D H M42325 A M42523 1. Visually check overall condition of assembly, including shaft and bushings, gears for wear, pitting, broken teeth, etc. 2. Use a feeler gauge to measure “go/no go” air gap (A) between end surface of combination gear and side surface of case half: • “GO” air gap should be 0.33—0.63 mm (0.013 — 0.025 in.) • “NO GO” air gap is anything greater. 3.
REPAIR POWER TRAIN I 3. For the intermediate shaft assembly (E), use a feeler gauge to measure “go/no go” air gap (C) between end surface of flange bearing (D) and washer (B): • “GO” air gap should be 0—0.25 mm (0—0.010 in.), • “NO GO” air gap is anything greater. 4. If either or both measurements result in a “NO GO” reading, shim washers (A and H) need to be added or worn components need to be replaced.
REPAIR POWER TRAIN —Exploded View— A E I H M42335 Intermediate and Drive Shaft Components. Shim washers (A) and (H) are found in Shim Kit. Inspect Differential/Axle Shafts Assembly: Disassemble Differential/Axle Shafts Assembly: F E D B A F C M42492 1. Put inward pressure on both axles (D and E) as you lift differential assembly (F) from lower case. E Left-Hand Short Axle D I Right-Hand Long Axle G H F M42826 1. Visually check overall condition of assembly. 2.
REPAIR POWER TRAIN TRANSAXLE ASSEMBLY— STX38 (SN 210001— ) & STX46 Assemble Drive/Intermediate Shaft Assemblies: B A D C NOTE: STX38 (SN 301383— ) transaxle differs slightly from STX38 (SN 210001—301382) and STX46 transaxle. IMPORTANT: Coat lightly all mating surfaces, except seal surfaces, with SAE 30 weight oil before assembly. Pay close attention to proper order and orientation of all components.
REPAIR POWER TRAIN —Exploded View of Intermediate and Drive Shaft Components— E F G I H M42335 Assemble Idler Combination Gear Assembly K STX38 (SN 210001—301382) and STX46 Transaxle: D J A B E F C G L M N M42325 M42327 9. Measure air gaps (K and N)—(see Inspect Drive/ Intermediate Shaft Assemblies). Make any changes in shim washer (M) and (J) thicknesses from Shim Kit to obtain proper air gaps. 10. When proper air gap is obtained, gears should drag slightly against feeler gauge.
REPAIR POWER TRAIN . H F E I J C D A K G B M42324 H 3. Install idler combination gear assembly (H) into lower case half. 4. Measure air gap (J) between shim washer (I) and face of case (K) (see Inspect Idler Combination Gear Assembly). 5. When proper air gap is obtained, assembly should drag slightly against feeler gauge. I J K L M42525 Assemble Input Shaft/Pinion Gear Assembly: IMPORTANT: DO NOT scratch or deform upper case half bore when installing needle bearings. A M42497 1.
REPAIR POWER TRAIN F C E B A D D C M42313 M42312 6. Turn upper case half over. 7. Install a shim washer (C) (from Shim Kit) of the proper thickness that allows enough clearance for E-ring (D) to be installed. “GO” air gap should be 0.25 mm (0.010 in.) or less. 8. Turn upper case half over and measure air gap between snap ring (L) and bevel pinion gear (K) (see Inspect Input Shaft/Pinion Gear Assembly). 9. If measurement results in a “NO GO” reading, shim thickness (C) needs to be changed. 10.
REPAIR POWER TRAIN STX38 (SN 301383— ) Transaxle 7. Install short cap screw (K) in right mounting bracket hole (G). 8. Install dowel pins (F) inside two center mounting bracket holes (Q). 9. Install striker plate (R) and thick friction puck (E) in backside recess of mounting bracket. B A D C M88992 1. Install shifter shaft rubber boot (B). 2. Coat detent balls (C) and springs (D) with John Deere Never-Seez and install in case bores. 3.
CONTENTS HYDROSTATIC POWER TRAIN CONTENTS Page HYDROSTATIC POWER TRAIN SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GENERAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 REPAIR SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 TORQUE SPECIFICATIONS (ALPHABETICAL ORDER) . . . . . . . . . . . . . . . . . . . . . 4 OTHER MATERIALS. . . . . .
NOTES 6-2 HYDROSTATIC POWER TRAIN 3/12/97
HYDROSTATIC POWER TRAIN SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Gear Teeth: Spur Gear (drive shaft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 teeth Differential Ring Gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 teeth Differential Bevel Pinion Gears (cross shaft) . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 teeth Differential Bevel Pinion Gears (axle shafts). . . . . . . . . . . .
SPECIFICATIONS HYDROSTATIC POWER TRAIN REPAIR SPECIFICATIONS Transaxle Components Wear Tolerances: Pump (Input) Shaft Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Visual Check Motor (Drive) Shaft Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Visual Check Axle Shaft Thrust Washers Wear Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HYDROSTATIC POWER TRAIN SPECIFICATIONS OTHER MATERIALS Transaxle Housing Case Half Sealant: . . . . . . . . . . . . . . . . . . . . . . . . . . . .John Deere Form-In-Place Silicone Gasket Sealant Pump Connector Pipe Plug Sealant: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .John Deere Pipe Sealant With Teflon® Approved Teflon® Sealant Tape. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Standard Roll Lubrication: Type . . . . . . . . . . . . . . . . . . . . .
COMPONENT LOCATION HYDROSTATIC POWER TRAIN COMPONENT LOCATION 1. Axle Shaft/Wheel Key (2 used) 49. Spacer (M10x20x20) 2. Left Axle Shaft 50. Cap Screw (M10x60) (3 used) 3. Left Axle Shaft Seal 51. Pump Filter 4. Left Axle Shaft Bushing 52. Motor Plate Dowel Pin (2 used) 5. Upper Case Housing 53. Pump Plate 6. O-Ring 54. Rolled Pins (M12x22) (2 used) 7. Fill Cap 55. Pump and Motor Center Block 8. Snap Ring 56. Motor Plate 9. Input Shaft Seal 57. Motor Cylinder Block 10. Snap Ring 58.
COMPONENT LOCATION HYDROSTATIC POWER TRAIN HYDROSTATIC TRANSAXLE 1 9 11 12 10 14 13 7 2 15 8 3 4 5 6 13 22—29 N•m (200—260 lb-in.) 16 21 44—59 N•m (390—521 lb-in.) 17 39 18 19 21 20 40 22 41 23 43 24 25 44 29 30 42 31 45 32 46 33 34 47 35 36 53 48 37 54 38 55 49 56 26 57 58 28 59 50 60 61 52 62 27 51 63 64 65 66 26 70 69 67 71 28 68 72 73 50 44—59 N•m 74 (390—521 lb-in.
COMPONENT LOCATION HYDROSTATIC POWER TRAIN TRACTION DRIVE SYSTEM COMPONENT LOCATION 14 9 15 10 12 13 11 6 16 17 5 7 3 18 8 4 19 20 21 2 25 22 23 26 24 27 1 32 29 31 28 33 30 34 36 35 37 38 41 40 1. Transaxle drive sheave 2. Frame weldment—idler adjustment 3. Carriage bolt (M8x35) 4. Park locking rod tension spring 5. Cap screw (M8x20) 6. Bushing 7. Tensioning strap 8. Park locking rod 9. Carriage bolt (M8x45) 10.
COMPONENT LOCATION HYDROSTATIC POWER TRAIN SHIFT LINKAGE SYSTEM COMPONENT LOCATION 7 3 6 5 4 2 8 10 34 1 9 33 32 31 30 11 29 12 28 13 25 14 24 27 23 26 19 15 22 16 20 18 17 21 M55831 1. Cap screw (M6x20) 2. Shift arm 3. Lock nut (M6) 4. Lock nut (M10) 5. Flange nut (M8) 6. Neutral return strap 7. Shift knob 8. Neutral return bushing 9. Rolled pin (M4x20) 10. Shift lever 11. Shift lever neutral return spring 12. Spacer 13. Support strap 14. Shoulder bolt 15. Cap screw (M10x25) 16.
THEORY OF OPERATION HYDROSTATIC POWER TRAIN THEORY OF OPERATION In this group the STX hydrostatic power train is separated into the following systems: TRANSAXLE AND SHIFT LINKAGE SYSTEM OPERATION Function: • Belt Traction Drive System • Transaxle and Shift Linkage System • Brake/Neutral Return System • Transport (Free-Wheeling) System BELT TRACTION DRIVE SYSTEM OPERATION The transaxle transmits power from the engine, through the belt traction drive system, through the transaxle’s hydraulic pump and mo
THEORY OF OPERATION HYDROSTATIC POWER TRAIN L M K J Q D R P O N M58268 K50 Version Shown M55850 When in neutral, the shift lever (D), shift bracket (F), turnbuckle link (E), bellcrank (G), link strap (H), and shifter shaft lever (I) hold the shifter shaft (J) and the variable-angle pump swashplate (O) in the neutral position.
THEORY OF OPERATION HYDROSTATIC POWER TRAIN Reverse: L M K J Q R D P O N M58269 K50 Version Shown M55852 D F When the shift lever (D) is moved into reverse position, the shift bracket (F) pivots in the opposite direction, pushing the turnbuckle (E) forward, pivoting the bellcrank (G), link strap (H), shifter lever (I), shifter shaft (J), and variable-angle pump swashplate (O) into reverse position.
THEORY OF OPERATION HYDROSTATIC POWER TRAIN Theory of Operation: B D M55800 A B C D N F E M G L H V I M55850 K J M58258 I H J O K P Q R M58259 L S G U T H I K R 3/21/97 M58252 When the brake pedal (A) is depressed, the bellcrank (B) and frame rod (F) rotate forward. This motion causes the brake rod (H) and neutral return strap (G), connected at the same point on the bellcrank, to move forward at the same time.
THEORY OF OPERATION HYDROSTATIC POWER TRAIN W X Y M58271 NOTE: Brake pedal has approximately 127 mm (5 in.) of travel. 1. The first segment of travel (W) is taking-up freeplay in the brake and return-to-neutral linkages. 2. The next segment of travel (X) is returning the shift linkage to neutral and engaging the brake. IMPORTANT: Full brake engagement (drive wheels stop turning) must not occur until shift linkage has returned to neutral completely.
THEORY OF OPERATION HYDROSTATIC POWER TRAIN TRANSPORT (FREE-WHEEL) SYSTEM OPERATION Function: The transport (free-wheel) system allows the operator to push the tractor while the engine is off, transmission in or out of either forward or reverse, and the brake released.
TROUBLESHOOTING HYDROSTATIC POWER TRAIN TROUBLESHOOTING ● Drive belt worn, frayed, glazed, or stretched— replace belt ● ● ● ● ● ● ● ● Bellcrank tensioning spring weak or broken— replace as necessary ● ● ● ● ● ● ● Brake pedal linkage out of adjustment—adjust properly ● ● ● ● ● ● ● ● ● ● ● Brake system components worn, bent, or broken—replace and adjust properly ● ● ● ● ● ● ● ● ● ● ● Shift lever linkage bent, worn, out of adjustment, or broken—replace or adjust pro
Fan loose or damaged— tighten or replace Shifts hard Noisy operation Leaking lubricant ● ● ● ● ● ● ● ● Incorrect type or volume of lubricant used—replace with correct type and volume ● ● ● ● ● Bleed procedure overlooked or improperly done—repeat procedure correctly ● ● ● ● ● ● ● Motor drive shaft or axle seals worn or damaged— replace seals ● ● Transaxle case halves cap screws loose or stripped—tighten or replace screws ● ● Poor application of transaxle case halves sealant—re
DIAGNOSIS HYDROSTATIC POWER TRAIN DIAGNOSIS Test Conditions: • Tractor on level surface. • Front wheels blocked. • Engine OFF. • Rear wheels raised off surface with axle housings on jack stands. Test/Check Point Normal If Not Normal 1. Drive belt Belt in good condition, not glazed, split, unraveled, or stretched. Replace drive belt as needed. 2. Fan Fan in good condition and tight. Tighten fan. Repair or replace as needed. 3.
DIAGNOSIS HYDROSTATIC POWER TRAIN 4 1 3 2 M55834 7 5 11 6 M58272 12 9 9 8 10 M58237 3/21/97 M55892 6 - 19
DIAGNOSIS HYDROSTATIC POWER TRAIN DIAGNOSIS CONTINUED Test Conditions: • Tractor operating in test area. • Tests run at engine slow idle and fast idle. • Engine at operating temperature. • Hydro run through full range of speeds in both directions. Test/Check Point 1. Engine performance. Normal Engine running throttle range. smoothly If Not Normal throughout Adjust, tune, or repair engine. 2. Belt traction drive system. Belt not slipping, squealing, or vibrating excessively.
DIAGNOSIS HYDROSTATIC POWER TRAIN 2 1 M55834 M55927 3 4 M58272 5 6 M58237 3/21/97 M55892 6 - 21
TESTS AND ADJUSTMENTS HYDROSTATIC POWER TRAIN TESTS AND ADJUSTMENTS 1. Test drive tractor to see if traction drive system pulls tractor up a 17° slope in lower 1/3 of forward range. 2. Look for a steady pull up the slope. 3. If test fails in any of the lower 1/3 range, the belt tension must be adjusted. TRACTION DRIVE SYSTEM Reason: To ensure shift, neutral return, and brake linkages and belt drive system maintain traction in lower 1/3 of forward speed range up a 17° slope.
TESTS AND ADJUSTMENTS HYDROSTATIC POWER TRAIN DRIVE BELT ADJUSTMENT B B A C E C D E D M58366 1. Lock park brake. c CAUTION Tensioning spring (B) is under high tension. Wear gloves and use a firm grip when stretching spring. M58266 2. Slowly engage lever (A) into over-center position (B). 3. Watch closely that actuating pin (E) moves inward all-the-way and, as lever snaps into over-center position, does not move outward at all. 4. If actuating pin (E) does move outward, loosen mounting nuts (C).
TESTS AND ADJUSTMENTS HYDROSTATIC POWER TRAIN SHIFT LINKAGE ADJUSTMENT 1. Safely raise rear of tractor off the surface and block the front wheels. Remove rear wheels to gain access to transaxle shift linkage and to safely check for creep in transaxle (axles turning while shift linkage is in neutral position without brake engaged). 2. Check that all shift linkage hardware is in good condition and tight. Replace components as necessary. F M58277 9. Loosen shift quadrant three mounting brackets (F). 10.
TESTS AND ADJUSTMENTS HYDROSTATIC POWER TRAIN C E D E M42596 H I M58276 F 2. Check shift linkage bellcrank spring tension by measuring spring length distance (E) between flanged nut and top anchor washer and adjust to specification. This will ensure shift lever will remain stationary wherever operator lets go of lever anywhere in shift quadrant. This adjustment may vary from one operator’s preference to the next. G J Specification: Bellcrank spring length (maximum) Production spring . . . . .
TESTS AND ADJUSTMENTS HYDROSTATIC POWER TRAIN K L M M58274 3. Look for a steady pull in all three lower gears up the slope. If tractor fails traction test, inspect traction drive belt: • if belt is excessively worn, stretched, glazed, or unraveling—replace it (see Inspect, Remove, and Install Traction Drive Belt in the Repair Section), • if belt is not excessively worn, make finite adjustments above or below specification to gain proper response in traction drive system.
REPAIR HYDROSTATIC POWER TRAIN REPAIR TRACTION DRIVE BELT REMOVAL/ INSPECTION/INSTALLATION I B NOTE: If drive belt is in good condition, it doesn’t have to be completely removed to take out the transaxle. Follow Removal Steps 1—4 below, then remove belt from transaxle drive sheave. A C P Removal— O 1. Park tractor on level surface and remove battery. 2. Remove mower deck. 3. Safely raise and block tractor to gain easy access to underside of frame.
REPAIR HYDROSTATIC POWER TRAIN TRACTION DRIVE BELT TENSIONING SYSTEM REMOVAL/ INSPECTION/INSTALLATION A. Transaxle drive sheave B. Washer C. Cap screw (M6x25) D. Adjustable idler weldment bracket E. Carriage bolt (M8x35) F. Cap screw (M8x20) G. Bushing H. Bellcrank I. Carriage bolt (M8x45) J. Tensioning spring K. Anti-vibration hose (early models only) L. Crankshaft drive sheave M. Drive belt N. Bellcrank idler O. Flange nuts (M8) P. Adjustable idler 1. Remove mower deck. 2.
REPAIR HYDROSTATIC POWER TRAIN POWER TRAIN LINKAGE SYSTEM REMOVAL/INSPECTION/ INSTALLATION 1-Cap screw (M6x20) 2-Shift arm 3-Lock nut (M6) 4-Lock nut (M10) 5-Shift link 6-Snap ring 7-Anchor washer 8-Spring 9-Friction disc 10-Bellcrank 11-Friction disc 12-Anchor washer 13-Stud (M10x76.5/M8x40) 14-Woodruff key (5/32x5/8 in.) 15-Lock nut (5/16 in.
REPAIR HYDROSTATIC POWER TRAIN TRANSAXLE REMOVAL AND INSTALLATION Removal 1. Safely raise and block rear of tractor off surface. 2. Safely support bottom of transaxle or have a helper hold transaxle in place when you remove final hardware (Steps 13—14). 3. Remove drive wheels, inspect key and keyways, washers, and snap rings. Replace as necessary. B 12. Remove transaxle to workbench. 13. Remove snap ring (E) to remove shift link (D). 14. Remove cap screw and lock nut (G) to remove shift arm (H).
REPAIR HYDROSTATIC POWER TRAIN Specification: Flange nut to right-front mounting bracket . . . . . . . . . . . . . . . . . . . . . . . . . . 15 N•m (132 lb-in.) Cap screw and nut to left-front mounting bracket . . . . . . . . . . . . . . . . . . . . . . . . . 15 N•m (132 lb-in.) Cap screws and nuts to frame . . . . . . . . . . . . . . 20.3—47.4 N•m (180—420 lb-in.) Shift arm cap screw and lock nut . . . . . . . . . . . . . . . . 9.5—14.9 N•m (84—132 lb-in.) Turnbuckle lock nut . . . . . . . . . . . . . .
REPAIR HYDROSTATIC POWER TRAIN Remove Reservoir Cover— Remove Brake Assembly— NOTE: If there is no damage to cover or upper case housing, you need not remove cover because there are no components inside the reservoir. 1 A 2 3 M58281 M58205 1. Remove four cap screws (A) to remove reservoir cover. 2. Inspect cover for cracks or holes, replace as necessary. 3.
REPAIR HYDROSTATIC POWER TRAIN Upper Case Half G H I M58274 6. Measure brake components individually. 7. Replace components as necessary and as a set only. Set brake assembly components aside for final assembly. See page 6-46 Brake Pad Adjustment. Lower Case Half Specifications: Brake Components Wear Tolerances— (G) brake puck (minimum) . . . . . . . 8 mm (0.3 in.) (H) brake lever (minimum). . . . . . . 25 mm (1.0 in.) (I) brake disc (minimum) . . . . . . 2.5 mm (.098 in.
REPAIR HYDROSTATIC POWER TRAIN Disassemble Transport (Free-Wheeling) Assembly– L K M A M55843 NOTE: Inspect transport actuating bracket and pin assembly (A) for wear or leakage to outside. If assembly is in good condition, just set lower case half aside for final assembly. B D C E F M55839 1. If wear or leakage is detected, remove e-ring (C), actuating bracket (D), and pin (F). 2. Remove and discard o-ring (E). Replace it with new o-ring every time assembly is removed or leaking. 3.
REPAIR HYDROSTATIC POWER TRAIN Inspect Differential Axle Assembly— A B A C B D D C H E F G E F C M58215 M58219 1. First, measure air gap between edge of swashplate slot (A) and shift blocks (D). If out-of-specification, replace shift blocks. 2. Lift shifter shaft assembly (E) and shift blocks (D) from upper case half mounting hole (B) and slot of swashplate (A). 3. Inspect mating surfaces of case hole (B) and end of shaft (H) for scoring or pitting. Replace as necessary. 4.
REPAIR HYDROSTATIC POWER TRAIN DIFFERENTIAL AXLE— DISASSEMBLY A A M58231 K-50 Long Axle Side M58229 A K-50 Short Axle Side A M58353 K-55 Long Axle Side B M58347 C K-55 Short Axle Side D 1. Remove short axle side thrust washer (A). B C M58230 D K-50 Long Axle Side M58228 K-50 Short Axle Side B C B D C D M58345 M58348 K-55 Short Axle Side 2. Turn c-ring (D) in its groove so gap (C) faces down to keep c-ring from falling down inside case. 3.
REPAIR HYDROSTATIC POWER TRAIN G R E M58222 G 8. Remove and discard axle seals (E) from both sides. Replace with new seals every time axles are removed. M58351 K-55 Version NOTE: One of the main differences in the K-55 version from the K-50 version are the two inner axle bushings (G) and their seat grooves (R). F M58223 G M58350 K-55 Inner Axle Bushings 9. Inspect upper case half outer left and right axle bushings for scoring, pitting, wear, or discoloration. 10.
REPAIR HYDROSTATIC POWER TRAIN PUMP, MOTOR, AND CENTER BLOCK—DISASSEMBLY I IMPORTANT: Loss of Hydro Power— STX38 (M00STXC210001—270000) STX38 (M00STXJ270001—290000) STX46 (M00STXG240001—270000) STX46 (M00STXL270001—290000) One or more piston springs may be missing in the pump or motor cylinder block. With the spring missing, piston washer may slip out of piston and damage surfaces of the cylinder blocks, plates, and center block. J K Q P O L N M M58209 A B C D E B C G H F M58248 5.
REPAIR HYDROSTATIC POWER TRAIN Remove Pump Input Shaft Assembly— D A E C B I F M55840 K-50 Version G H M58214 K-50 Version C D E M58213 K-50 Version I F A G C H M58358 B K-55 Version M55840 K-55 Version C 3. Inspect ball bearing (F) for scoring, pitting, discoloration, and other wear. 4. If damaged, remove two snap rings (D) to remove and replace bearing. 5.
REPAIR HYDROSTATIC POWER TRAIN Disassemble and Inspect Pump and Swashplate— G A B C D E F I H L J IMPORTANT: If thrust bushings and swashplate ramps are damaged, they must be replaced as a set. If swashplate recess machined surface or bushing are damaged, replace with new swashplate (bushing is not serviced separately). If bronze pump plate or center block are damaged, they both must be replaced.
REPAIR HYDROSTATIC POWER TRAIN TRANSAXLE ASSEMBLY IMPORTANT: Coat all components lightly with fresh oil before assembly, especially any mating surfaces between components.
REPAIR HYDROSTATIC POWER TRAIN Install Pump, Swashplate, and Shifter Shaft Assemblies— IMPORTANT: Read these next four procedures completely before proceeding. L K A M58239 M58243 1. Install swashplate thrust plates (A). B IMPORTANT: Hold fingers tightly between all five pistons so pistons don’t drop out of cylinder block during assembly and spline alignment. C D E F M58240 2. Install new o-ring (E) on shifter shaft. 3.
REPAIR HYDROSTATIC POWER TRAIN Install Pump, Motor, and Center Block Assembly— D C F A G E B F H M58245 N H M L 4. Install motor drive shaft assembly with longer cylinder block splines (G), spring (H), and snap ring (F) through fixed swashplate hole as shown. J I K L M58247 5. Coat motor (I) and pump (J) machined surfaces of center block and backside of bronze motor (L) and pump (K) plates with grease to hold bronze plates in place. 6.
REPAIR HYDROSTATIC POWER TRAIN Install Differential Axle Assembly— M58222 A 1. Apply grease to new axle seals (A) and install them into each end so they are flush with outside case lip and open side of seals to inside. H M58231 K-50 Long Axle Side B C H D F M58353 E M58230 2. Wrap tape around short (B) and long (E) axle shaft splines and c-ring grooves to protect new seals. K-50 Long Axle Side K-55 Long Axle Side 6. Install thrust washer (H).
REPAIR HYDROSTATIC POWER TRAIN C H M58229 K-50 Short Axle Side D E F M58352 H K-55 Version Shown 2. Install new filter (C). 3. Install bypass valve push pin guides (D), springs (E), and push pins (F). M58347 I K-55 Short Axle Side 8. Repeat thrust washer procedures for short axle side. G H J Install Filter, Magnet, Wheeling) Assembly— and Transport (Free- M58239 4. Install new o-ring (J) on actuating pin and install in lower case half bore (G). A B I M58211 1.
REPAIR HYDROSTATIC POWER TRAIN TRANSAXLE CASE HALVES— ASSEMBLY BRAKE ASSEMBLY— INSTALLATION Upper Case Half A B B D M58208 C Lower Case Half M55842 Brake Pad Adjustment K-50 Version Shown 1. Make sure mating surfaces of transaxle case halves are clean. 2. Apply a solid bead (B) of John Deere Form-In-Place Silicone Gasket Sealant around lower case half. Be sure to stay to the inside of the mounting holes. 3. Be sure to apply a solid bead around two inner holes (D). 4.
REPAIR HYDROSTATIC POWER TRAIN RESERVOIR COVER AND BREATHER VALVE—ASSEMBLY FAN AND DRIVE SHEAVE— INSTALLATION A A B M58235 D 1. If reservoir cover was removed or replaced, apply a solid bead (A) of John Deere Form-In-Place Silicone Gasket Sealant around the cover, staying to inside of holes. C M58236 C B 1. Assemble fan to transaxle drive sheave using two fan holes (C). Two washers and nuts (B) go under fan. Bottom fan lip (D) goes towards transaxle. E A D M58234 2.
REPAIR HYDROSTATIC POWER TRAIN TRANSAXLE BLEED PROCEDURE A M58210 NOTE: This procedure is used before the transaxle is installed. If the transaxle is already installed see Standard Transaxle Bleed Procedure this page. 1. Turn transaxle over. 2. Remove recess plug (A) from bleed port stack. 3. While you pour new oil into hole, have a helper hold transaxle off bench and turn brake disc to rotate motor shaft and bleed internal pump, motor, and center block assembly. 4.
CONTENTS STEERING CONTENTS Page STEERING SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 TEST AND ADJUSTMENT SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 SERVICE EQUIPMENT AND TOOLS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 TESTS AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 STEERING BACKLASH . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NOTES 7-2 STEERING 3/12/97
STEERING SPECIFICATIONS SPECIFICATIONS TEST AND ADJUSTMENT SPECIFICATIONS Steering Backlash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Minimum without binding SERVICE EQUIPMENT AND TOOLS NOTE: Order tools from your SERVICE-GARD Catalog. Some tools may be available from a local supplier. Inside Puller and Slide Hammer. . . . . . . . . . . . . . . . . . . . . . .
TESTS AND ADJUSTMENTS STEERING TESTS AND ADJUSTMENTS D STEERING BACKLASH C E B A M51991 M51991 NOTE: To adjust steering backlash, put four washers on bottom of sector shaft (B). Put enough washers on top to reduce play. Adjust quantity of washers top and bottom to minimize backlash without binding. 5. Install washers (E) and cotter pin (C). 6. Install and fasten tie rods. 7. Install steering wheel on top of steering shaft (D) and fasten with mounting hardware. 8.
REPAIR STEERING REPAIR STEERING GEAR ASSEMBLY— REMOVAL 1. Remove battery and safely raise front of tractor. 2. Remove fuel tank and dash panel (see Remove and Install Fuel Tank and Dash Panel Assembly in Engine Section). K B M51994 NOTE: Steering pinion gear (K) can no longer be removed from the steering shaft. There may be 0—3 washers installed above gear (K). These washers are not interchangeable with other washers on the shaft.
REPAIR STEERING PEDESTAL BUSHINGS— REPLACEMENT A M51989 1. Inspect four bushings (A) installed in steering sleeves of pedestal. If worn or damaged, replace them individually or as a set. 2. Clamp pedestal to stationary bench. 3. Use a slide hammer puller set up with inside jaws to remove four bushings. 4. Install new bushings using a rubber hammer.
CONTENTS MISCELLANEOUS CONTENTS Page MISCELLANEOUS SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 SERVICE EQUIPMENT & TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 OTHER MATERIAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 WHEELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CONTENTS 8-2 MISCELLANEOUS 3/12/97
MISCELLANEOUS SPECIFICATIONS SPECIFICATIONS SERVICE EQUIPMENT & TOOLS NOTE: Order tools from your SERVICEGARD catalog. Some tools may be available from a local supplier. Inside Slide Hammer Puller . . . . . . . . . . . . . . . . . . . . . . . . . . . Remove wheel bearings. OTHER MATERIAL Dubois’ MPG-2® Multi-Purpose Grease . . . . . . . . . . . . . . . . . . . . . .
WHEELS MISCELLANEOUS WHEELS REAR WHEELS—REMOVAL & INSTALLATION FRONT WHEELS—REMOVAL & INSTALLATION 1. Safely lift and support tractor. 1. Safely lift and support tractor. 2. Remove plastic cap. B A C D E A F M55832 2. Remove plastic cap (C), E-ring (D) (gear) or snap ring (F) (hydro), and outer washer (E). 3. Remove wheel. M57056 3. Remove snap ring (A) and wheel. NOTE: Front wheels are installed with valves to the inside. 4. Grease spindles with specified grease. 5.
WHEELS MISCELLANEOUS FRONT WHEELS— TOE-IN & CAMBER Reason: To insure tractor toe-in is within specification. Procedure: Measure toe-in using the following procedure: 1. Equalize front tire pressure (12 psi). 2. Turn wheels so they are pointing straight ahead. If one wheel has more toe-in than the other, use steering wheel logo to determine straight ahead. X C Rear Front X B X A Floor 3. Measure distance (A) from the floor to the center of wheel hub. 4.
FRONT AXLE MISCELLANEOUS FRONT AXLE REMOVAL & INSTALLATION Specifications: Pivot Cap Screw . . . . . . . . . . . . . . . . 54 N•m (40 lb-ft) Muffler-To-Engine Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19—30 N•m (168—265 lb-in.) Tie Rod Nuts (STX30 & STX38 SN —210000) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 N•m (16 lb-ft). 1. Safely support front of tractor. 2. Remove front wheels. 3. Disconnect draft arms (D) from axle.
MOWER DECKS MISCELLANEOUS MOWER DECKS DIAGNOSIS IMPORTANT: During hot weather the mower deck may become covered with a soot like material that looks like engine exhaust or belt dust. This black soot like material is a type of lawn mold. Do not change belts. There is no problem with the tractor or mower deck. Test/Check Point Normal If Not Normal 1. Rear draft arm brackets. STX38—Only Mower deck does not fall off lift system.
MOWER DECKS MISCELLANEOUS B A M85801 7. Install LH Bracket (M116689) on the right side of tractor. Fasten lower end of bracket (A) with nut removed in Step 4. 8. Fasten upper end of bracket (B) to slot in lift arm with M6x20 cap screw and lock nut. Tighten lock nut. 9. Replace rear tires and lower machine safely to ground. STX38 (M00STXB139616—210000) 135 mm (5.3 in.) 117 mm (4.6 in.) 1. Reshape RH bracket (M116688) to 135 mm (5.3 in.) hole centers. 2. Reshape LH bracket (M116689) to 117 mm (4.6 in.
MOWER DECKS MISCELLANEOUS LIFT LINKAGE REPAIR— STX30 & STX38 (SN —210000) Latch Handle Lift Handle Latch Spring Cotter Pin Lift Assist Spring Cap Screw Latch Left Bracket Half Ratchet Spacer Adjustment Bolt M52014 NOTE: The STX38 uses a heavier assist spring, connected to a carriage bolt in a more rearward position than on the STX30. Disassemble 1. Remove battery and mower. 2. Remove cap screws. Remove handle. 3. Remove cotter pins, washers, and springs. 4. Remove handle from latch. 5.
MOWER DECKS MISCELLANEOUS STX38 (SN 210001— STX46 (SN 240001— )& ) 1. Remove battery and mower. 2. Check for worn or damaged components. 3. Adjust latch quadrant using slotted holes, if necessary, for smooth engagement with latch. 4. Install and adjust mower. 5. Install battery.
MOWER DECKS MISCELLANEOUS 30-INCH MOWER DECK Lock Nut Cap Screw Flange Nut Washer Belt Guide Flange Nut Idler Idler Sheave Bushing Bushing Spacer Cap Screw Key Cap Screw Washer Washer Ball Bearing Idler Lock Nut Spacer Nut Lock Nut Hub Washer Washer Bushing Lever Washer Ball Bearing Lock Nut Bushing Washer Extension Spring Nut Snap Ring Bracket Pin Pin Snap Ring Washer Spring Lock Pin Arm Bushing Nut Snap Ring Washer Wheel Washer Cap Screw Strap Adjuster Shaft
MOWER DECKS MISCELLANEOUS 38-INCH MOWER DECK (SN —210000) Washer Bracket Bushing (SN —100000) Bracket Cap Screw Spring Locking Pin Bushing (SN 100001— ) Spacer Bushing Bolt Ball Bearing Lock Nut Extension Spring Lock Nut Key Extension Spring Cap Screw Cap Screw Arm Bracket Nut Sheave Spacer Lock Nut Nut Washer Ball Bearing Washer Bushing Lever Cap Screw Washer Pin Lock Nut Torsion Spring Chute Lock Nut Nut Hub Snap Ring Wear Plate Sheave Washer Snap Ring Sheave Reinforce
MOWER DECKS MISCELLANEOUS 38-INCH MOWER DECK (SN 210001—270000) Belt Shield Adjustable Link Flange Nut (12 Used) Cap Screw Idler LH Draft Arm Bushing Bushing Spring Pin (2 Used) Tensioning Spring Idler Arm Pin (2 Used) Belt Bushing Cap Screw Cap Screw Eye Bolt Washer Idler RH Draft Arm Hinge Pin Cap Screw (6 Used) Hinge Bracket Lock Nut Push Lock Nut Nut (3 Used) Spindle Assembly Mower Deck Spacer Hinge Spring Spring Pin (2 Used) Cap Screw Washer (2 Used) Draft Rod Cap Screw Spindle
MOWER DECKS MISCELLANEOUS 38-INCH MOWER DECK (SN 270001—595000) Adjustable Link LH Draft Arm RH Draft Arm Bushing Spring Pin (2 Used) Belt Shield Flange Nut (12 Used) Cap Screw Idler Bushing Tensioning Spring Idler Arm Pin (2 Used) Belt Adjustable Link Cap Screw Flange Nut Eye Bolt Spindle Assembly Cap Screw (6 Used) Washer Idler Eye Bolt Lock Nut Hinge Pin Hinge Bracket Push Nut Lift Stop (Export Only) Lock Nut (3 Used) Spacer Hinge Spring Cap Screw Spring Pin Mower Deck Washe
MOWER DECKS MISCELLANEOUS 46-INCH MOWER DECK (SN 240001—270000) Rubber Stop (2 Used) Flange Nut (12 Used) RH Shield Idler Tensioning Spring Bushing LH Shield Idler Arm Bushing LH Draft Arm Cap Screw Adjustable Link Spring Pin (2 Used) Spindle Assembly (3 Used) Eye Bolt Pin (2 Used) Adjustable Link Flange Nut Flange Nut Idler Idler Cap Screw Spacer Cap Screw Cap Screw Mower Deck Lock Nut (3 Used) RH Draft Arm Hinge Pin Spring Pin (2 Used) Cap Screw Hinge Bracket Washer (2 Used) Lock
MOWER DECKS MISCELLANEOUS 46-INCH MOWER DECK (SN 270001—595000) Rubber Stop (2 Used) Flange Nut (12 Used) RH Shield Idler Bushing Adjustable Link Spring Pin (2 Used) Spindle Assembly (3 Used) Pin (2 Used) Adjustable Link LH Shield Idler Arm Bushing LH Draft Arm Cap Screw Tensioning Spring Eye Bolt Bushing Flange Nut Flange Nut Idler Idler Cap Screw Spacer Cap Screw Flange Nut RH Draft Arm Eye Bolt Lock Nut (3 Used) Mower Deck Flange Nut Hinge Pin Spring Pin (2 Used) Cap Screw Hinge
MOWER DECKS MISCELLANEOUS SPINDLES— STX30 & STX38 (SN —210000) 4. Press on inner and outer races of bearing to remove bearing and spacer. 5. Invert hub and press out bearing. 6. Inspect and replace parts as necessary. 7. Press bearing into hub until it contacts snap ring. 8. Insert spacer in hub. Fill area around spacer half full with John Deere Multipurpose Grease or equivalent. 9. Support bearing and press bearing against spacer. 10. Install snap ring and grease outside of bearing. 11.
MOWER DECKS MISCELLANEOUS A B J I D C K M55889 A B C D D M58341 1. Remove shield(s) (D) and belt (A). DO NOT remove nuts (B) or sheaves (C) from spindles. c CAUTION M55887 3. Remove spindle bearing guard(s) (I) and mounting hardware (K) to remove any spindle assembly (J). Inspect spindle assemblies for broken welds or bent flanges. Replace parts as necessary. 4. Install each spindle assembly in reverse order. Tighten mounting hardware to specification. 5.
MOWER DECKS MISCELLANEOUS MOWER BLADE ADJUSTMENT C A Reason: To insure mower deck blades cut evenly. Procedure: B M85800 Difference in blade lower tips M85800 1. Check blade alignment by measuring the difference in height, from one lower tip to the other tip. NOTE: Some mismatch between blades is normal. As a general rule if the difference between lower tip of one blade is less than 1/4 inch (6 mm) different than the lower tip of the other blade, it will be undetectable. No action is necessary.
MOWER DECKS MISCELLANEOUS BLADE DRIVE BELT REMOVAL/ INSTALLATION—STX30 1. Remove ignition key and disconnect spark plug wire. 2. Lower mower. Installation 6. Install sheave and belt. 7. Tighten cap screw (B) to specification. 8. Connect spring (A). Specification Cap Screw. . . . . . . . . . . . . . . . . . . . . 95 N•m (70 lb-ft) BELT REMOVAL/INSTALLATION STX38 (SN 210001— ) STX46 (SN 240001— ) 1. Remove ignition key and disconnect spark plug wire. 2. Lower mower. A M51979 A 3.
MOWER DECKS MISCELLANEOUS MOWER DECK BLOWOUT—STX46 Blade Lock Nut Bolt Bolt Bolt Insert Lock Nut Retainer Plate Wing Nut M85812 NOTE: Blowout reduction kit (AM124031) is used to provide sufficient lip surface around deck to install conventional blowout reduction kit like on 48/54” decks. Reason: Grass blows out front of deck. Seems worse when mulch kit has been installed. Procedure: 1. If deck is equipped with a mulch kit, start with adjustable screen fully raised.
SEAT REMOVAL & INSTALLATION MISCELLANEOUS SEAT REMOVAL & INSTALLATION MOWER FRAME MOUNTING PLATE Removal Removal Center Panel Outer Fascia Cap Screws Seat Adjuster Pivot Rod Seat Seat Connector M76615 M76614 Bushing Flat Plastic Washer Metal Spring Washer Flat Metal Washer Cap Screw M85843 1. Lift operator’s seat forward to allow access to adjuster hardware. 2. Disconnect seat switch electrical connector. 3. Remove four cap screws holding seat and seat adjuster to mounting plate. 4.
INDEX A Air Intake System Components . . . . . . . . . . .3 - 29 Alternative Lubricants . . . . . . . . . . . . . . . . . .2 - 20 Analyze Piston Ring Wear . . . . . . . . . . . . . . .3 - 42 Analyze Piston Wear . . . . . . . . . . . . . . . . . . .3 - 42 Analyze Valves . . . . . . . . . . . . . . . . . . . . . . .3 - 34 Anti-Corrosion Grease . . . . . . . . . . . . . . . . .2 - 22 Armature Tests . . . . . . . . . . . . . . . . . . . . . . .4 - 78 Assemble Piston Assembly . . . . . . . . . . . . . .
INDEX Gear Power Train Other Materials . . . . . . . . .5 - 7 Gear Power Train Repair Specifications . . . . .5 - 5 Gear Power Train Service Parts Kits . . . . . . .5 - 7 Gear Power Train Shift Linkage Adjustment . . . . . . . . . . . . . . . . . . . .5 - 37 Gear Power Train Shift Linkage Removal & Installation . . . . . . . . . . . . . . . . . . . .5 - 56 Gear Power Train Tests & Adjustments . . . . .5 - 34 Gear Power Train Torque Specifications . . . .
INDEX Hydrostatic Transaxle Brake Assembly Installation . . . . . . . . . . . . . . . . . . . .6 - 46 Hydrostatic Transaxle Brake Components Wear Tolerance Specifications . . . . .6 - 4 Hydrostatic Transaxle Brake Torque Rating Specification . . . . . . . .6 - 3 Hydrostatic Transaxle Breather Valve Assembly Removal . . . . . . . . . . . . . .6 - 32 Hydrostatic Transaxle Component Location . . . . . . . . . . . . .6 - 7 Hydrostatic Transaxle Components Wear Tolerance Specifications . . . . . . . . . .
INDEX L Lap Valves . . . . . . . . . . . . . . . . . . . . . . . . . .3 - 36 Lift Linkage Repair . . . . . . . . . . . . . . . . . . . . .8 - 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 - 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 - 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 - 10 Lubricant Storage . . . . . . . . . . . . . . . . . . . . .2 - 20 M Measure Camshaft End Play . . . . . . . . . . . . .3 - 38 Measure Piston Ring End Gap . . . . . . . . . . .
INDEX V Valves & Valve Lifter Repair Specifications . . .3 - 4 Valves— Lap. . . . . . . . . . . . . . . . . . . . . . . . .3 - 36 Valves— Inspect . . . . . . . . . . . . . . . . . . . . .3 - 35 W Wheel & Tire Specifications . . . . . . . . . . . . . .2 - 5 Wheels— Front and Rear . . . . . . . . . . . . . . . . .8 - 4 Toe-in and Camber Adjustment . . . . .8 - 5 Wire Color Abbreviation Chart . . . . . . . . . . . .
INDEX NOTES INDEX - 6 3/20/97
