ONAN TORO POWER PLUS P216, 18, 20, 24 ENGINES - HORIZONTAL Table of Contents – Page 1 of 2 SAFETY PRECAUTIONS GENERAL PROTECT AGAINST MOVING PARTS BATTERIES FUEL SYSTEM EXHAUST SYSTEM EXHAUST GAS IS DEADLY! COOLING SYSTEM KEEP THE UNIT AND SURROUNDING AREA CLEAN CAUTION GENERAL INFORMATION INTRODUCTION ENGINE MODEL REFERENCE SPECIFICATIONS DIMENSIONS AND CLEARANCES P216, P218, P220 P216,P218,P220 P224 P224 ASSEMBLY TORQUES SPECIAL TOOLS ENGINE TROUBLESHOOTING OIL SYSTEM CRANKCASE OIL OIL FILTER CHANGE CRANK
ONAN TORO POWER PLUS P216, 18, 20, 24 ENGINES - HORIZONTAL Table of Contents – Page 2 of 2 IGNITION AND BATTERY CHARGING IGNITION SYSTEM DESCRIPTION IGNITION TIMING CONTINUITY TEST IGNITION COIL SPARK PLUGS BATTERY INSPECTION BATTERY JUMP STARTING FLYWHEEL ALTERNATOR ALTERNATOR OUTPUT TEST TYPICAL WIRING DIAGRAM STARTING SYSYTEM ELECTRIC STARTER SERVICE STARTER REMOVAL STARTER DISASSEMBLY STARTER ASSEMBLY INSPECTION AND TESTING STARTER MOUNTING ENGINE DISASSEMBLY DISASSEMBLY/ASSEMBLY SUGGESTED DISASSEMBLY O
Service Manual 1709 P216,18,20,24 TORO Power Plus Engine Tractors&RidingMowers
Safety Precautions It is recommended that you read your engine manual and become thoroughly acquainted with your equipment before you start the engine. Fuel System DO NOT fill fuel tanks while engineis running. DO NOT smoke or use an open flame in the vicinity of the engine or fuel tank. Internal combustion engine fuels are highly flammable. This symbol if used warns of immediatehazardswhich will result in severe personal injury or death.
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General Information Use only Genuine Tom Plower Plusreplacement parts to ensure qualityand the bestpossible repair and overhaul results. When ordering parts, always use the complete model and spec number as well as the serial number shown on the nameplate. This manual deals with specific mechanical and electricalinformationneededbyenginemechanicsfor or overhauling the troubleshooting, servicing, repairing, engine.
Specifications This manual containsSI metric equivalents that follow immediately in parentheses after theU.S. customary units of measure.
Dimensions and Clearances P216. P218. P220 . . All clearances given at room temperature 70°Fof(21°C) All dimensionsin inches (approximate millimeter dimensions in parentheses) unless otherwise specified . DESCRIPTION CYLINDER BLOCK Cylinder Bore Honed Diameter Maximum Allowable Taper Out-of-Round Main Bearing Inside Diameter (Without bearing) Main Bearing Inside Diameter (Installed service bearing) Camshaft Bearing Bore (Installed service bearing) ............................ (82.52) 3.2490 ...........
P216. P218. P220 MINIMUM Inches (mm) MAXIMUM Inches (mm) PISTON PIN Clearance in Piston Clearance in Connecting Rod Diameter 0.00004 0.0002 0.6875 (0.001) (0.005) (1 7.46) 0.00064 0.0007 0.6877 (0.016) (0.01 8) (1 7.47) PISTON RINGS Clearance Top Groove Ring End Gapin Cylinder 0.0030 0.0100 (0.076) (0.254) 0.0080 0.0200 (0.203) (0.508) INTAKE VALVE Stem Diameter Clearance (Stemto Guide) Valve Face Angle 0.2795 (7.099 (0.025) 0.0010 0.
P224 DESCRIPTION MINIMUM Inches (mm) CYLINDER BLOCK Cylinder Bore Honed Diameter Maximum Allowable Taper Out-of-Round Main Bearing Inside Diameter (Without bearing) Main Bearing Inside Diameter (Installed) Camshaft Bearing Bore (Bearing Installed) 2.1 870 2.0015 1.3757 (50.
P224 DESCRIPTlON INTAKE VALVE Stem Diameter Clearance (Stem to Guide) Valve Face Angle (8.700) 0.3425 0.0010 INTAKE VALVESEAT Seat Cylinder Head Bore Diameter Seat Outside Diameter Valve Seat Width Valve Seat Angle (39.74) 1.5645 (39.85) 1.5690 0.0310 EXHAUST VALVE Stem Diameter Clearance (Stemto Guide) Value Face Angle 0.3410 0.0025 EXHAUST VALVESEAT Seat Cylinder Head Bore Diameter Seat Outside Diameter Valve Seat Width Valve Seat Angle 1.2510 1.2550 0.0310 ........................................
Assembly Torques Thetorquevaluesgiven in Table 1 havebeendeter-Tighten all studs,nuts,andcapscrewsasrequiredto minedforspecificapplications.Standardtorquevalueskeepthemfromworkingloose.Refer to the PARTS must not be used where those listed in Table 1 apply. MANUAL for the location of washers and capscrews. The engine assembly torques given here will assure All proper tightness without danger of stripping threads. threads mustbe clean and lubricated with new engine oil before torquing. TABLE 1.
Engine Troubleshooting ASOLINE ENGINE FUEL SYSTEM INTERNAL ENGINE LUBRICATION SYSTEM THROTTLE AND GOVERNOR M-1686
Oil System CRANKCASE OIL Refer to Periodic Maintenance Schedule (located in the Operator's Manual) foroil change interval.If operating in extremelydusty, high ambient, or low ambient conditions, changeoil more often. Hot crankcase oil can cause burns if His spilled or splashedskin. on Keep fingers and hands clear when removing the dl drain plug and wear protective clothing. Crankcasepressure can blow out hot oil and causeserious burns. Do NOT check d l while the engine is Operating.
OIL FILTER CHANGE Refer to Periodic Maintenenace Schedule (located in the Operator’s Manual) for oil filter change interval. If operating in extremelydusty,highambient, or low ambient conditions, changeoil filter more often. Spin off oil filter element and discard it. Thoroughly clean filter mounting surfaceand make sure new gasket is inserted in the element. Applythin a filmof clean oil to the gasket.
PRESSURE LUBRICATION Check oil pump thoroughly for worn parts. Oil pump to prime it before reinstalling. Except for gaskets pickand All engines use an oil pump to provide a constant flow of up cup, component parts of the pump are not available oil to the engine parts. The oil supply collectsin the oil ifany parts, individually. Install a new pump assembly base whereit is picked upby theoil pump pick-up cup. worn,. to control are A by-pass valve is used oil pressure.
Fuel System CARBURETOR Note: See pages 7-4-1, 74-2 for Spec G Engines. All carburetors have a fixed main jet An optional fixed main jet is available for altitude compensation above 5,000 feet. Carburetor speed Settings 1. Start the engine andallowi t to warm up thoroughly (at least10 minutes). Some equipment manufacturers may require higher throttle stop speed and governor low speed rpm settings. Referto equipment manufacturer's Operator's Manual for the correct rpm settings.
+ I FIGURE 2. CARBURETORADJUSTMENTS CARBURETOR OVERHAUL Note: See pages 7-4-1, 7-4-2 for Spec G Engines. Carburetionproblemsthatarenotcorrectedbymixture adjustments are usually a result of gummed-up fuel passages internalparts.Themosteffective solution is a carburetor overhaul. FIGURE 3. CARBURETOR ASSEMBLY orworn In general, overhauling a carburetor consists of disassembly, athorough cleaning, and replacementwon of parts. Carburetor overhaul kits are available.
NEEDLE \ BEND TANG HERE TO BEND FLOAT ARM HERE TO FUEL Cleaning and Repair Reassembly and Installation 1. Soak all metal components not replaced in carburetor cleaner. Do not soak non-metal floats or other non-metal parts. Follow the cleaning manufacturer's recommendations. 2. Clean all carbon from the carburetor bore, especially careful where the throttle and choke plates Be seat. not to plug the idle or main fuel ports. 1. Install needle valve, main jet, and float assembly.
PULSATING-DIAPHRAGM FUEL PUMP Pulsating-diaphragm fuel pumps, or pulse pumps, rely on changesin crankcase vacuum to create a pulsating movementofthepumpdiaphragm. As the engine's pistons moveoutward, a vacuum is created.This it vacuum is transmitted to the pump diaphragm causing to pull back and suck fuel into the pump. As the engine's pistons move inward, crankcase vacuum is reduced and the diaphragm return spring pushes the pump diaphragmforward, forcingfuelthroughthepump outlet.
Supplement to492-4006,492-4007 Date:1-95 P216/P218/P220/P224/P220V Service Manual PURPOSE This supplement transmits the revisions to the Service Manual necessary for covering the Spec G engines listed above. Note that the nameplate on a Spec G engine will have the statement: “This engine meets1995-1998 California emissions regulations for ULGE engines.
CARBURETOR (BEGINNING SPEC G) Carburetor Replacement Other than replacing the carburetor main fuel jet (fixed-type) with the optional high-altitude jet (Figure &), fuel mixture adjustments should not be attempted. Nor should the carburetor be overhauled. Instead, a malfunctioning carburetor shouldbe replaced.
AIR CLEANER ELEMENT AIR PLATE . FIGURE 5. AIR CLEANER ASSEMBLY AIR CLEANER If air cleanerbecomes too dirty, engine will not receive sufficientair to run properly. Symptoms: Loss of power, flooding, hard starting and overheating. Engine is equipped with a paper element. If the engineis it must be removed, equipped with an element wrapper, cleaned, and oiled every 25 hours of operation; more often under extremely dusty conditions. 1.
THROTTLE STOP SCREW GOVERNOR CONTROL LINKAGE GOVERNOR SPRING SIDE PULLGOVERNOR FRONT PULLGOVERNOR FIGURE 6. VARIABLE SPEED GOVERNOR ADJUSTMENTS On sidepull governors the governor spring is set by the factory in the third hole of the governor arm (third hole from pivot). On front pull governors the governor spring is set by the factory in the second hole of the governor 1. Disconnect linkage(A) from one of holes(C). armadapter(secondholefrompivot).
Ignition and Battery Charging IGNITION SYSTEM DESCRIPTION Failure to ground spark tester away from spark plug hole may result in ignition of cyiinder gasesandmay cause severe personal injury. Thisengine is equippedwithanelectronicbattery ignition system. Both spark plugs fire simultaneously, thustheneedforadistributor is eliminated.The electronic ignition module is located on the enginegear 2. Pull spark plug wires off spark plugs and remove cover behind the flywheel.
IGNITION TIMING The ignition timing is preset at the factory and is not adjustable. For troubleshooting purposes,it is possible to make an approximate check of the ignition timing usingreferencemarksontheblowerhousingand flywheel (Figure 2). This check can be performed by a continuity test. 4. Rotate the flywheel slowly by hand in the clockwise direction until the voltmeter reading switches from approximately 1 volt to battery voltage.
SPARK PLUGS Keep the battery terminals clean and tight. Push the cable terminal down flush with or slightly below the top 6). After making connections, of the battery post (Figure Check or replace spark plugs as recommended in the coat the terminals with light a application of petroleum Periodic Maintenance Schedule(located in Operator's jelly orgrease to retard corrosion. Manual). Replace spark plugs that show signs of fouling or electrode erosion.
Do not allow the posltive and negativecable ends to touch each other because itwill short the battery causing hazardous arcing, which can cause severe personal injury. 4. Attach one end of the negative booster cable (black) to negative (-) terminal of booster battery. Attach otherendofnegativecable ground on to asolidchassis Never jump start a frozen battery. To do so can cause the battery to explode.
Keep these points in mind when testing or servicing the flywheel alternator: ALTERNATOR OUTPUT TEST Use a volt-ohmmeter, such as the Simpson 270, when testing the charging system. 1. Be sure engine is being run long enough and fast enough to recharge battery after each start. Charging system tests requirefulla charged battery. Alternator 1. Check battery voltage with unit not running. If not output is reduced in direct proportion to engine rpm.
TABLE 1. TESTING 20 AND 35 AMPERE SYSTEMS STATOR RESISTANCE PROCEDURE Refer to Alternator Output Test 0.06 to 0.10 Ohms 0.10 to 0.19 Ohms 13.6 to 14.7 VDC Approximately 24 VAC 0.06 to 0.
TYPICAL WIRING DIAGRAM STARTER *AMMETER (OPTIONAL) ACCESSORIES START OIL PRESSURE SWITCH N C LOW PRESSURE WARNING LIGHT OR HORN WITH OIL PRESSURE SWITCH FOR LIGHT & y e - *FUSE STARTER *AMMETER These typical wiring diagrams show the basic wiring necessary for operation of the engine. Your engine may differ in circuitry and features depending on how the equipment manufacturer chose to configure the final product.
Starting System ELECTRIC STARTER 1. Remove both battery cables from battery. Discon- nect ground cable first. Normally the starter will require little or no service other if through thanpossiblebrushreplacementHowever, accident or misuse, the starter requires service or from starter. will providetheinformation overhaul,thefollowing necessary to perform this service. 2. Disconnectbatterycableand electrical leadwires 3. Remove starter motor.
ring 8. Push stopper toward pinion and remove snap (Figure 2). 9. Removestopper and overrunning clutch from armature shaft. CLUTCH \ STOPPER a=- ST SNAP RING FIGURE 2. REMOVINGOVERRUNlNG CLUTCH 10 Inspect starter for damaged or worn parts. 11. Repair or replace all damaged or worn parts as needed. Starter Assembly I 4. Lubrication:When starter motor is assembled apply grease to each of the following points (Recommended grade: Multitemp PSNo.
10. Install and tighten the two through capscrews. 11. Install solenoid plunger in lever. Secure solenoid to front bracket with two machine screws. COMMUTATOR BARS 12. Install wire lead to the terminal “M” on solenoid. 13. Afterassembly,adjust pinionclearance.Pinion be 0.02 to 0.08 inch (0.5 to 2.0 mm); clearance should if not, check as follows (Figure 4): A. Connect starter to a battery. Close switch. This will shift pinion into cranking position. B.
Commutator Inspection:If commutator is dirty or dis00 to 000 commutator colored,cleanwithnumber paper. Blow grit out of armature after cleaning. Overrunning Clutch:Inspect pinion and spline teeth for wear or damage. If commutator is scored, rough, or worn, turn it down in a lathe. If pinion gear is worn or damaged, inspect flywheel ring It should turn free when turned gear also. Rotate pinion. in one direction, andlock when turned in the opposite direction.
Brush Replacement Cut oldpositivebrushfrompigtail at the brush.Be careful not to damage field coil. Clean 1/4 to 3/8 inch (6.5 to 9.5 mm) of brush end of pigtail with sandpaper or emery cloth. (Figure9). Starter Mounting Before installing starter motor. make sure the starter mounting Surface on the engine base is clean and free of oil. To installstarterusethefollowingprocedure.The starter pinion gear lash does not require adjustment 1.
Engine Disassembly DISASSEMBLY/ASSEMBLY Whencompleteenginedisassembly is necessary, first remove all complete assemblies. Individual assemblies such as fuelpumpandcarburetorcanbedisassembledgear. and repaired at another time. Suggested Disassembly Order 1. Drain crankcase. 2. Disconnect all exhaust and electrical lines. 3. Remove engine fromits mountings and place on a suitable bench or work stand. 4. Remove all housings, shrouds, blower housings, etc. 5. Remove flywheel, using a puller. 6.
VALVE SYSTEM Tappet Adjustment The engine is equipped with adjustable valve tappets. A properly functioning valve system is essential for good The valve tappet clearance should be checked and engine performance.All engines utilize an L-head type adjustedasspecified in the PeriodicMaintenance valve design as shown in Figure 1. Access to the valve Schedule (located in the Operator’s Manual).
Warpage occurs chiefly in the upper stem due to its exposure to intense heat. Out-of-round wear follows when the seatis pounded bya valve whose headis not If a valve faceis burned in line with the stem and guide. or warped, orif the stem is worn, install a new valve. Drivlng out old guides can damage thee guide or tappet bores. Be careful not tostrike guide bores with driveror allow guide to strike tappet bores during removal.
Valve Spring: Check valve springs for cracks, worn Valve Seat Removal: Remove carbon and combustion ends, distortion, and tension.If spring ends are worn, depositsfromvalve seat Selectproperpullersize check valve spring retainer for wear. Check for spring determined by inside diameter of valve seat On some distortion by placing spring on a flat surface next to a pullers use a new seat as a guide to adjust puller depth square. Measure height of spring and rotateit against (Figure 4).
TAPPETS Very little wear takes place on tappet diameters orin tappet bores. If the clearance between tappet and bore in cylinder block exceeds specifications, replace the tappet. Inspect the tappet faces which contact camshaft lobes for roughness, scuffing, or concave wear. Replace any worn tappets. If tappets are worn, inspect camshaft for wear. VALVE FACE AND SEAT GRINDING Before installingnew valves or previously used valves, If used inspect valve seats for proper valve seating.
GEAR COVER FLYWHEEL Removing the flywheel is a relatively simple process, but After removing the mounting screws, tap the gear cover thefollowingprocedure must be followedtoavoid gently with asoft faced hammerto loosenit. damage to the gear case and possible injury to the operator. When installing the gear cover, make sure pin thein the gear cover engages the nylon lined (smooth) in thehole 1. Turn the flywheel mounting screw outward about governor cup. Turn the governor so cup the nylon lined two turns.
THE DIMENSION S H O W N O N DRAWING WILL A S INDICATED CENTER PIN SNAP BALL GOVERNOR GOVERNOR CUP FIGURE BALL GOVERNOR GOVERNOR CUP DETAILS GOVERNOR CUP With the gear cover removed, the governor cup can be taken off after removing the snap ring from the camshaft center pin. Catch the flyballs while sliding the cup-off (Figure 10). TIMING GEARS If replacement of either the crankshaft gear or the camshaft gear becomes necessary, always install both gears new.
CRANKSHAFT 4. Turn the crankshaft until the piston is at the bottom rod nuts. Lift of itsstroke and remove the connecting the rod bearing cap from therod and push therod and piston assembly out through the top of the cylinder using hammer a handle.Do not scratch the crankpin andcylinderwallwhenremovingthe piston androd. GEAR PULLER 5. Mark each piston and rod assembly so they canbe returnedto their respective cylinders after overhaul. Keep connecting rod bearing caps with their respectiverods. 6.
FIGURE 15. CHECKING RING SIDE CLEARANCE have deep nicks, signs of fractures, scored bores, bores with dimensions which exceed that specified in DIMENSIONSAND CLEARANCES. Measuring Pistons: 1. Proper piston tolerances must be maintained for satisfactory operation. k FIGURE 14. PISTON GROOVE CLEANING Refer to DIMENSIONS AND CLEARANCES to determine where to measure piston be to sure the total clearance follows specifications. Follow the procedures given below when inspecting pistons and connectingrods.
Measuring PistonRings: 1. Install the piston ring in the cylinder bore. Invert the piston and push the ring to the endof ring travel, about halfwayinto the bore, which trues the ring end gap. Check the gap with a feeler gauge (Figure17). After removing pistons, crankshaft, cylinder heads, etc., inspect block for cracks and wear. If block is still serit for cleaning as follows: viceable, prepare 1. Scrapeall old gasket material from block.
2. Record measurements taken at top andbottom of piston travel as follows: A Measure and record as “ A the cylinder bore diameter (parallel to crankshaft) near the top of cylinder bore. B. Measureand record as “B’ cylinder bore diameter (parallel to crankshaft) at the bottom of piston travel. RING WEAR AREA C. Measureand record as “C” cylinder bore diameter (perpendicular to crankshaft) near the top of cylinder bore. D.
DeglazingCylinder Bores Deglaze the cylinder bores ifthere are noscuff marks andnowear or out of round beyond specifications before installing new rings. Deglazing gives a fine finish, 4. Make aninitial rough cut, followed by a finish cut. but doesnotenlarge cylinder diameter,so the original Then hone cylinder bore to the specified oversize. pistons with new rings may still beused. 3. Cleanbaseofboringbarbeforebar is setup.
CRANKSHAFT Clean crankshaft thoroughly and inspect journals for scoring, chipping, cracking, or signsof overheating. If crankshaft has overheated, is scored, or excessively worn, reconditioning or replacement will be required. Examine bearing journals for cracks if overheating has occurred. Measure crankshaft main bearing and connecting rod to check for journals at several places on their diameter roundness and taper.
In the rear bearing plate, install the bearing flush to 1/ 6 4 inch (0.40 mm) below theend of the bore. Be sure to align the oil holes in the bearing with the oil holes in the bearing bore (Figure 21). The oil passage must be at least halfopen. Lubricate bearing after installation. If head of lockpin isdamaged, use side cutters or Easy Out tool to remove and install new pin. Oil grooves in thrust washers must face the crankshaft, and washers each washer must be flat (not bent).
CHECKING CONNECTINGROD BEARING CLEARANCE WITH PLASTIGAUGE 1. Make certain that all parts are marked or identified so they are installed in their original positions. Using a clean dry cloth, thoroughly clean all oil from rod. If connecting crankshaft journal and connecting rod bearing inserts are being replaced (P224 only), install them in rod and cap. 2. Place a piece of correct size Plastigauge in the bearing cap the full width of the journal surface and about 1/4 inch (6.35mm) off center (Figure24). 3.
P216, P216, P220 Install one fastener and tighten to 5 ft-lbs (7 Nm). Repeat this for the other fastener. Tighten both fasteners down to the torque specified in ASSEMBLY TORQUES. PISTON ASSEMBLY 1. Lubricate all parts with engine oil. 2. Position piston on its respective rod and install the pin. P224 Install and tighten the nuts evenly in steps, to the torque specified in ASSEMBLY TORQUES. 3. Install the rings on the pistons starting with the oil control ring (Figure 26).
CYLINDER HEADS 3. Use new head gaskets and clean both heads the and the cylinder block thoroughly where the head Remove the cylinder heads for carbon cleaning and gaskets rest. gasket change at intervals specified in the Periodic MaintenanceSchedule (located in theOperator's Manual). 1. Use a 1/2 inch (13 mm) socket wrench to remove cylinder headbolts or nuts. Lift headsoff. (37°C) beforeremoval.
P224 Installation 1. Place a head gasket on the cylinder head and alignengine damage. the stud holes in the gasket with the instud the holes cylinder head. While holding the gasket against the3. cylinder head, carefully install the cylinder head on the engine. Do not attempt to slide the gasket over the studs without the cylinder head behind it or the gasket may tear. Follow the head torque sequence shown in Figure 30.
I Product information andspecificationsare shown herein as of thetime of printing. Wheel Horse Products, Inc. reserves the right to change productspecifications. designs and standard equipment without noticeand without incurring obligation.
