SB4253E02 Jan.
Important Safety Information Most accidents involving product operation, maintenance and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills and tools to perform these functions properly.
Index Specification Testing and Adjusting Torque Converter.............................................. 5 Forward and Reverse Control Group................. 5 Transmission Solenoid...................................... 5 Forward / Reverse Clutch Elements .................. 6 Valve Block Elements ....................................... 7 Valve Spring in Transmission Bearing Plate ...... 8 Tightening Torques ........................................... 9 Transmission .......................................
Specification Forward and Reverse Control Group Torque Converter (1) Torque for screws (four) that hold clamp to hand control switch………..3.4 to 3.9 N·m (30 to 35 lb·in) (2) Torque for bolts (two) that hold clamp to steering column……………….2.8 to 3.4 N·m (25 to 30 lb·in) (1) Torque for six bolts that hold torque converter drive plate to the flywheel ........... 45 ± 7 N·m (33 ±5 lb·ft) Apply a bead of LOCTITE NO.242 Sealant to inner radius of the clamp, prior to assembly.
Forward / Reverse Clutch Elements New 0.5mm (0.0197 In) 2.2 0.08 (0.0866 0.0031 In) New Snap ring Wom 0.35mm(0.0138 In) minimum a) Outer clutch Disc d) Piston return spring Length under test force ................ 23.1 mm (0.91 in) Test force ........................969.9 ±5 N (218.0 ± 11 lb) Free length after test (nominal) ......... 51 mm (2.0 in) Outside diameter.......................... 95.5 mm (3.74 in) 3 0.05mm (0.1181 0.0020 In) e) Clearance between piston and pressure disc ..................
Valve Block Elements Tighten to 50±7 N·m (37±5 Ib·ft) Tighten to 0.6 N·m (0.44 Ib·ft) min SECTION A-A Tighten to 25±4 N·m (18.5±3 Ib·ft) Tighten to 5±1 N·m (3.7±1 Ib·ft) Tighten to 5.5±1.5 N·m (4±1 Ib·ft) A C Tighten to 50±5 N·m (37±3.7 Ib·ft) D,E Tighten to 50±7 N·m (37±5 Ib·ft) B Tighten to 50±7 N·m (37±5 Ib·ft) D) Spring (outer) Length under test force…………22.22 mm (0.87 in) Test force………………...29 to 34 N (6.5 to 7.6 lb) Free length after test (nominal)….31.7 mm (1.25 in) Outside diameter………………..
Valve Spring in Transmission Bearing Plate Tighten to 45 N·m (33.2 Ib·ft) Converter Inlet Valve A 2-Springs Tighten to 45 N·m (33.2 Ib·ft) Converter Outlet Valve A) Spring Length under test force…………….30 mm (1.18 in) Test force…………….......18.1 ± 1.8 N (4.07±0.4lb) Free length after test(nominal)...43.25 mm (1.70 in) Outside diameter…………………10.7 mm (0.
Tightening Torques Transmission Power Train 9 Specifications
Power Train 10 Bolt 28 N m (20.7 Ib ft) Apply Loctite 242 to thread Bolt 115 N m (84.9 Ib ft) Apply Loctite 242 to thread Bolt 115 N m (84.9 Ib ft) Apply Loctite 242 to thread _8 N m (59.0+ _5.9 Ib ft) Bolt 80+ Adjust to (Slightly Oiled) 19.6 N m (14.5 Ib ft) drag (See Instructions) Shims (See Instructions) Grease Bearing Bolt 285 N m (210.3 Ib ft) With Molycote BR2 Apply Loctite 242 to thread Nut 50 N m (36.9 Ib ft) (See Instructions) Spacer and Shims (See Instructions) Nut 150 N m (110.
Final Drives and Wheels D, G Model Trucks Dual Drive wheels GC Model Trucks 1 1 2 2 3 4 3 4 5 5 6 Oil Cooled Disc Brake Type Oil Cooled Disc Brake Type (1) Apply LOCTITE NO.242 Thread Lock to threads of spindle bolts. Torque for bolts that hold spindle to drive axle housing ....................115 ± 14 N·m (85 ± 10 lb·ft) (1) Apply LOCTITE NO.242 Thread Lock to threads of spindle bolts. Torque for bolts that hold spindle to drive axle housing……………..
Drive Tire Installation GC20, GC25 Models GC30, GC32 Models-Wide Axle WARNING The drive tire must be installed as shown below. Failure to do so will decrease the stability of the truck, and can cause injury to the operator. GC20, GC25 Models Install the tire so that the edge of the tire is even with the outside edge of the wheel. GC30, GC32 Models GC30, GC32 Models-Narrow Axle Narrow Axle : Install the tire so there is distance (X) between the edge of the tire and the inside edge of the wheel.
Drive Wheel Installation D, G Model Trucks GC Model Trucks 1 1 (1) Tighten wheel mounting bolts to a torque of ……………………….644 ± 34 N·m (470 ± 25 lb·ft) Use a crisscross procedure to tighten nuts. (1) Tighten wheel mounting bolts to a torque of ……………………….
Drive Axle Mounting Group 1 Special shoulder Bolt Chassis Standard Bolt Drive Axle Housing 2 (1) Torque for two nuts that hold the axle to the chassis……………..…488 ± 27 N·m (360 ± 20 lb·ft) (2) Torque for two nuts that hold the axle to the chassis.......... ..…..….
System Operation General Information 3 4 1 Power Flow (1) Drive axle. (2) U-joint. (3) Transmission. (4) Engine. The basic components of the power train are engine (4), Transmission (3), U-Joint(2), Drive axle(1) and the final drives and wheels. Power from yoke of drive axle is sent through a spiral bevel gear set to the differential. The differential sends power out through the axles to the final drives and wheels. Two axle shafts connect the differential to two final drives.
The torque converter has four main parts : housing (4), impeller(pump) (3), turbine(1) and stator(2). The housing is connected to the engine flywheel through a flexplate. Impeller (3) and housing (4) are welded together and turn with the engine flywheel at engine speed and in the direction of engine rotation. Turbine (1) turns the transmission input shaft. Stator (2) is installed stationary on stator support (5) by a freewheel clutch that allows one way rotation of the stator.
Transmission 11 3 9A 10 2 1 4 9 16 5A 6 14 5 15 14A 8 7 13 12 (1) TC Housing. (2) TM Bearing Plate. (3) TM Housing. (4) Torque Converter. (5) Input Shaft. (5A)Input Shaft Gear. (6) Oil Pump. (7) Forward Gear. (8) Forward Clutch. (9) Reverse Shaft. (9A) Reverse Shaft Gear. (10) Reverse Clutch. (11) Reverse gear. (12) Output gear. (13) U-joint. (14) Quill Shaft. (14A) Coupling. (15) PTO Pump. (16) Axle Lubrication Pump.
Transmission Power Flow – Forward With the transmission control in forward, which will pressurize the forward clutch (8), power will flow from the engine through the torque converter to drive the oil pump (6) and the input shaft (5), also the quill shaft (14). Since the forward clutch (8) locks the forward gear (7) to the input shaft, the power flows through the forward clutch (8), the forward gear (7) to output gear (12) which is in mesh with the forward gear.
Transmission Power Flow – Reverse With the transmission controls in reverse, which will pressurize the reverse clutch (10), power will flow from the engine through the torque converter to drive the oil pump (6) and the input shaft (5) also the quill shaft (14). Since the reverse clutch (10) is closed, power will flow through input shaft gear (5A) which is in mesh and drives reverse shaft gear (9A) and reverse shaft (9).
Transmission Lubrication Schematic Oil Cooler TC Relieve Valve Oil for lubrication of the clutch shaft bearings and cooling the clutch discs and plates comes from the outlet passage of oil cooler. Lubrication oil is also splashed inside the transmission case. Lubrication oil is especially important for cooling the clutches. High temperatures can be caused during repeated shifting of the lift truck.
Transmission Hydraulic System (1) Transmission Oil Sump. (2) Oil Pump. (3) Primary Filter. (4) Main Valve. (5) Orifice. (6) Inching Valve. (7) Modulating Valve. (7A) Load Piston. (7B) Modulating Valve Orifice. (8) Selector Valve. (9) Solenoid Valve Forward. (10) Solenoid Valve Reverse. (11) Forward Clutch. (12) Reverse Clutch. (13) Relief Valve. (14) Torque Converter. (15) Relief Valve. (16) Converter Bypass. (17) Oil Cooler. (18) Torque Converter Supply Bypass.
The transmission hydraulic system is explained in three sections. The first section is the oil pump, filter, torque converter and oil cooler systems. The second section is the transmission lubrication system. The third section is the transmission hydraulic control system which controls the lift truck direction control. 4 Pump, Filter, Torque Converter and Oil Cooler Systems 6 The oil for the operation and lubrication of the transmission is made available by pump (2).
Power Train 23 Systems Operation
Neutral Position When the transmission is in NEUTRAL position with the engine running, oil is pulled from reservoir and the strainer assembly (1) to pump (2). From there, pump oil flows through the primary filter (3) to main relief valve (4). Oil will also flow through orifice (18) to lubricate the torque converter during hot, low speed conditions. When the pump pressure reaches 895 kPa (130 psi), relief valve spool (4A) will move to the left side and most of the pressure oil flows to the torque converter.
Power Train 25 Systems Operation
Forward Direction When the transmission is in FORWARD, the oil flow from the reservoir, through the pump, primary filter, torque converter and oil cooler circuits will be the same as explained in NEUTRAL position. Oil will flow from the main relief valve to inching valve (6). Without inching (inching pedal up and valve in), oil flows around and through the center of reducing spool (6A) to the bottom of the spool. The oil, at the bottom, pushes the spool up to the position shown.
Power Train 27 Systems Operation
Reverse Direction When the transmission is in REVERSE, the oil flow from the reservoir, through the pump, primary filter, torque converter and oil cooler circuits will be the same as explained in NEUTRAL position. Oil will flow from the main relief valve to inching valve (6). Without inching (inching pedal up and valve in), oil flows around and through the center of reducing spool (6A) to the bottom of the spool. The oil, at the bottom, pushes the spool up to the position shown.
Power Train 29 Systems Operation
Forward Direction During Inching When the transmission is in FORWARD (or REVERSE) during INCHING, the oil flow from the reservoir, through the pump, filter, torque converter and oil cooler circuits will be the same as explained in NEUTRAL position. Oil will flow from the main relief valve through a passage, to inching valve (6). Inching valve (6) lets the operator control the oil pressure to forward clutch (11) between 280 and 0 kPa (40 and 0 psi), which permits a partial engagement of the clutch.
Transmission Control Valve Basic Control Schematic DR DR DR FWD CLUTCH REV CLUTCH SOLENOID SOLENOID DR DR DR PUMP The control schematic is shown below. The system consists of 2 valve bores: 1. Modulating valve 2.
Modulating valve function SPRING MODULATING VALVE LOAD PISTON ORIFICE DR REACTION PLUG DR DR FLOW TO SELECTOR SPOOLS PUMP Figure 1 If Force 1 is too large then the valve would be forced to the right, opening the clutch circuit to supply, and increasing the value of Force 2 so it balances Force 1. By regulating clutch pressures between supply and drain, valve forces are balanced. The modulating valve consists of 5 basic elements: 1. Orifice 2. Springs 3. Load piston 4. Modulating valve 5.
Modulating valve movement during clutch fill Modulation of clutch to top pressure Figure 3 Figure 2 MODULA TION When a new direction is selected by the operator, the selector spools open up a circuit to the new clutch piston. System pressure drops as the new clutch piston is stroking. This drop in supply pressure causes a force imbalance on the modulating valve / reaction slug pressure becomes smaller.
Selector spools Figure 5 The selector spool circuits are arranged in such a way that once a gear (forward or reverse) is selected the opposite solenoid supply is shut off and drained. This is done to prevent any electrical or malfunction of the other solenoid from giving a sudden and unexpected shift. In addition the two selector spools are arranged so they cannot select both forward and reverse at the same time because they mechanically interfere with each other. The selector spools have two areas: 1.
Drive Axle 8 10 9 3 7 6 11 12 4 5,5A,5B,5C 2 1 11 6 12 7 3 9 8 10 (1) Axle Housing. (2) Carrier (3) Brake Housing Left/Right. (4) Pinion. (5) Crown wheel/differential. (6) Drive Shaft Left/right. (7) Ring Gear/Hub. left/right. (8) Pneumatic Tire Wheel Flange Left/right. (9) Multi-disc brake left/right. (10) Spindle. (11) Axle Mounting Pads. (12) Mast Mounting Hooks. The Axle Consists of 4 main sections a) The carrier housing (2), pinion (4) and crownwheel with differential assembly (5).
Axle power flow Power is transmitted by the transmission output shaft to the pinion (4) which meshes with and drives the crownwheel (5), which is mounted to the differential. 4 5 The differential is part of the drive axle. It is a single reduction unit with a differential drive gear fastened on the differential case. When the lift truck moves in a forward direction and there is the same traction under each wheel, torgue in each axle and pinion gears (5B) are balanced.
Axle Lubrication Schematic PUMP PUMP 3 3 11 22 33 The axle is lubricated by means of the transmissionmounted lubricant pump (2) which gets oil from the axle suction port (1) and supplies it to the hub section pressure parts (3) to lubricate and cool hub drive and multi-disc brakes. Oil returns to the sump through the drive shaft bearings and axle housing.
3. Actuate the controls for the forward direction and then for the reverse direction. The actuation must give the same positive action to the hydraulic control circuit for clutch engagement in both directions. Testing and Adjusting Troubleshooting Troubleshooting can be difficult. A list of possible problems and corrections is on the pages that follow. 4. Remove and check the filter element for loose particles. Check the strainer behind the transmission oil plug for foreign material.
g. Leakage inside the transmission. Worn or broken metal seal rings on input or reverse shaft. Worn or broken seals around clutch piston. Modulating valve assemblies stuck Because of contaminated oil Check List during Operation Problem: Engine starts with directional control switch in FORWARD or REVERSE. Probable cause: 1. Directional control switch is defective 3. External oil lines are not connected correctly. Problem: Transmission shifts with parking brake engaged. 4.
7. Low oil flow through converter. Converter relief valve stuck open (converter bypass orifice plugged) Check List from Operation Noise Problem: Noise in NEUTRAL only. 8. Incorrect use of vehicle. Loads are too heavy for the lift truck. Probable cause: 9. Too much inching operation (slipping the clutch plates and discs). 1. Worn one-way clutch in torque converter. 2. Low oil level (pump cavitation). 10. Too much stalling of torque converter. 3. Worn bearing next to pump. 11.
6. Too much or too little gear backlash. 2. Loss at bevel input pinion shaft. 7. Loose or worn pinion bearings. a. Lubricant above specification level. 8. Loose or worn shaft bearings. b. Wrong kind of lubricant. 9. Loose or worn differential bearings. c. Restriction of axle housing breather. Problem: Noise at different intervals. d. Pinion oil seal worn or not installed correctly. Probable cause: Problem: Drive wheels do not turn. 1. Bolts on drive gear not tightened correctly.
Problem: Pressure to one clutch is low. Problem: High converter charge pressure. Probable cause: Probable cause: 1. Clutch piston seal alignment is not correct, oil leaks through. 1. A plugged converter bypass orifice. 2. A restriction inside the converter assembly. 2. Seal rings on shaft or clutch piston seals are broken or worn. 3. A plugged oil flow passage. 3. Modulating valve assembly stuck. Problem: Low converter charge pressure. Problem: Low pump pressure.
Problem: High stall speed in one direction. Problem: Modulation spool problems. Probable cause: 1. There is a leak in the clutch circuit. 1. Slow or no modulation of both clutches (If only 1 clutch does not modulate correctly then the problem is either with the selector spool or it is a problem in the transmission). 2. There is a failure in that clutch assembly (clutch slipping). Probable cause: Problem: Selector spool problems. 1. orifice plugged with debris 1.
Transmission Pressure Test Most problems in the hydraulic circuit can normally be found when the pump pressure is checked. If more information is necessary, gauges can be installed at each pressure tap location. Locations of the pressure taps and procedures for testing are given as follows. If any of the pressures are not correct, refer to Troubleshooting For Problems and Probable Causes. Tools Needed Pressure Gauge Group 1 WARNING 1.
Pressure Tap Locations – Transmission Control Group Main Pressure Tap 6 Reverse Pressure Tap 5 Forward Pressure Tap 4 Converter Charge Pressure Tap Converter Outlet Pressure Tap 2 Temperature Sensor To Cooler From Cooler Lubrication Pressure Tap 7 Power Train 45 Testing and Adjusting
7. Check lubrication pressure at pressure tap (7) with the transmission in neutral. Converter Stall Test NOTE: Make sure that the transmission oil is at the correct temperature for operation before tests are made. a. If lubrication pressure is low, see Problem: Low lubrication pressure in Troubleshooting. b. If lubrication pressure is high, see Problem: High lubrication pressure in Troubleshooting. The converter stall test is a test to check engine power.
The stall speed must be the same in FORWARD and REVERSE. If the stall speed is high in FORWARD and REVERSE, check the following: NOTICE To make sure that the transmission oil does not get hot, do not hold the transmission in a stall condition for more than ten seconds. After the transmission is stalled, put the controls in NEUTRAL and run the engine at 1200 to 1500 RPM to cool the oil. a. Check for air in the oil. b.
Maintenance Transmission Change Filter Grease Parking Brake Lever Oil Filler And Dipstick Pin And Nut Of Parking Brake Oil Drain Plug and Suction Strainer ATTENTION: When changing oil, replace filter and clean suction strainer.
Drive Axle Combined Oil Filler and Dipstick Brake Cooling Port Pump Suction Port Brake Cooling Port Oil Drain Plug Port ATTENTION: Clean suction strainer when replacing oil.
Electric Control System Tests Directional Control Switch Check 1. Put the directional control lever in neutral. Remove the cover from the front side of front cockpit unit. Tools Needed Digital Multimeter 1 NOTE : Refer to Schematic. Checks on the transmission directional control electrical circuit can be done with a Digital Multimeter. All voltage checks are made at the wiring harness connectors with the ignition switch ON, DO NOT start the engine.
5. Turn the ignition switch OFF and put the multimeter on the 200 ohm range. Transmission Control Harness Check 9. Disconnect the connector of Engine harness from the connector of transmission harness. Check the continuity of engine harness from one end to the other. Repair or replace the wiring harness if there is no continuity. 6. Check continuity between pins 4 and 7 of directional switch connector with the switch in neutral. Forward and then reverse the positions.
Transmission Directional Control Schematic for G15/35S-5 Power Train 52 Testing and Adjusting
Transmission Directional Control Schematic for D15/35S-5 (Cummins Engine A2300 / B3.
Transmission Directional Control Schematic for D20/33S-5, D35C-5 (Yanmar Engine 4TNV98) Power Train 54 Testing and Adjusting
Transmission Directional Control Schematic for D20/33S-5, D35C-5 (Yanmar Engine 4TNE98) Power Train 55 Testing and Adjusting
Inching Pedal Adjustment WARNING To prevent personal injury, when the inching pedal is adjusted, move the truck to a clear area that is level. Keep all other personnel away from the lift truck. Use lifting equipment or a safe method to lift the front of the lift truck until the drive wheels are off the floor. Put wood blocks or jack stands of the correct capacity under it to hold it in this position while the inching pedal is adjusted.
The adjusting procedure is as follows. Be sure that the air bleeding of brake system should be done in advance. 85.5 1 mm 3. Adjust the height (C) of inching pedal and brake pedal. (C) should be 110mm at the same level. (A) 82.5 mm 235 1 mm (B) (E) 4. Adjust the gap (D) for engaging brake pedal by inching pedal. (D) should be approx. 9.5mm. 1. Adjust the length (A) from the spool to the connection point of yoke. (A) should be 85.5 ± 1mm.
Adjustments on Drive axle 4. Calaulate the shimpack thickness according to the following formula. Shimpack thickness = A-(127+B+C) Example) if A=160.50, B=32.00, C=+0.05 Then, shimpack thickness =160.50-(127+32.00+0.05) = 1.45mm Axle, Pinion, crown gear * To minimize the measuring error, measure three places at least and average them. 1. Measure the depth from center of diff. carrier to the seat of pinion bearing cup. (Dimension A) 5. Shims of calculated thickness laid into bearing seat. 2.
8. Install bearing nuts for the correct cap position and lightly torque them to achieve bearing preload. 11. When drag is correct, mark position of nuts both on nuts and bridge. 9. Tap on differential on both sides to achieve correct bearing cone position, rotate differential (3-5 times). 12. After marking of position remove differential assy. 10. Check drag 19.6 N.m (14.5 lb.ft) on rotating differential.
Installation of Pinion 4. Tap bearing cone to correct position(Rotate pinion 3-5 times) 1. Install cup of rear pinion bearing 5. Assemble yoke and nut and tighten flange nut to 180 ±15 N·m (133±11 lb·ft) 2. Install spacer and shims on pinion (basic thickness 1.5mm (0.059 in)). 6. Measure the rolling torque. The value of rolling torque should be 1.5~2.0 N·m (1.1~1.5 lb·ft) 7. If the rolling torque exceeds 2 N·m, add one shim and if it is lower than 1.5 N·m, subtract one shim 3. Install bearing cone. 8.
Adjustment of Crown Wheel 3. Tap on both sides of the differential to achieve correct position of bearing cups. 1. Torque crown wheel bolts to 80 N·m (59 lb·ft). 4. Check backlash between pinion and crown gear in 3 different positions. Backlash shall be 0.15-0.20 mm (0.006-0.008 in) 2. Install differential assy., to previously mounted position (rotate both nuts simultaneously to maintain bearing preload). 5. Check contact face by rotating pinion in both directions, hold back crown wheel.
9. Position not correct. 6. Check contact area position and correct in accordance with specification if neccessary. 10. After correct adjustment of contact area secure differential nut with split pin. 7. Position not correct 8. Correct position.
Adjustment of Wheel Bearings 4. Remove wheel nut for lockwasher installation. 1. Assemble outer hub bearing without lockwasher. 5. Install lockwasher and nut. 2. Tighten wheel nut to 135 ± 14 N·m (100±10 lb·ft). 6. Tighten nut to 50 ±5 N·m (37±3 lb·ft). 3.
