554 and 574 Forwarders Power Train Gearshift Pressures - Test - 574 Forwarder 1FM434-UP Caterpillar


Gearshift Pressures - Test - 574 Forwarder 1FM434-UP
`
1.1. Gearshift Valve Pressure Test and Adjust
2.2. Testing the Gearshift Valve Pressure
3.2. Adjusting the Gearshift Pressure
4.1. Eight Wheel Drive Disengage Pressure Test and Adjust
5.2. Testing the Eight Wheel Drive Disengage Pressure
6.2. Adjusting the Eight Wheel Drive Disengage Pressure

The following procedure is used in order to verify that the correct oil pressure to the transmission gearbox is within specification. The specifications are listed in Table 1 and Table 2.

Table 1
Pressures to Shift the Transmission Gearbox    
Shift Pressure     Speed Selection    
-     Low Speed     High Speed    
Minimum Pressure    
1500 kPa (215 psi)    

1500 kPa (215 psi)    
Maximum Pressure    
3500 kPa (500 psi)    

3500 kPa (500 psi)    

Table 2
Pressure to Shift the Eight Wheel Drive Disengage    
Minimum Pressure     Maximum Pressure    

1500 kPa (215 psi)    

3500 kPa (500 psi)    

Table 3
Required Tools    
Qty.     Part No.     Description    
2     8T-0856     Pressure Gauge (0 to 6,000 kPa (0 to 870 psi))    

  1. The gearshift valve is located on the inside of the left frame rail under the cab.



    Illustration 1g00916293

    (1) Eight wheel drive disengage pressure tap. (1a) Gearshift pressure tap.

  1. Connect a 8T-0856 Pressure Gauge (0 to 6,000 kPa (0 to 870 psi)) to each pressure tap (1) .

    Note: Two pressure taps are installed on the gearshift valve. One pressure tap, (1a) reads the gearshift pressure. One pressure tap, (1) reads the eight wheel drive disengage pressure.

Gearshift Valve Pressure Test and Adjust

Testing the Gearshift Valve Pressure

  1. Start the machine.

  1. Warm the oil in the transmission gearbox and the hydraulic tank to the normal operating temperature.



    Illustration 2g00932267

    Mode Selector Switch

  1. Place the machine in the ROADING MODE.

  1. If a new solenoid valve was installed, shift the transmission at least 12 times into a gear that uses the solenoid valve.

  1. Place the direction selector switch in the NEUTRAL position.

  1. Place the parking brake switch in the ON position.

  1. Run the engine speed at low idle.

  1. Move the speed selector switch to the speed that is being tested. This will cause the gearshift valve to shift the gearshift cylinder that is located on the side of the transmission gearbox.

    Note: Do not depress the accelerator pedal.

  1. Read the pressure on the 8T-0856 Pressure Gauge (0 to 6,000 kPa (0 to 870 psi)) for the transmission gearbox speed that is being tested.

    The specified pressure for gear engagement is listed in Table 1.

  1. Move the direction selector switch to the NEUTRAL position and turn off the engine.

  1. If the gearshift pressures are within specification, disconnect the test equipment. Adjustment is not necessary. If the gearshift pressures are not within specification, proceed to the section that is entitled "Adjusting the Gearshift Pressure".

Adjusting the Gearshift Pressure

  1. If the gearshift pressure is not within specifications, use the following procedure in order to adjust the gearshift valve.

  1. Start the machine.

  1. Ensure that the hydraulic oil is at the normal operating temperature.



    Illustration 3g00932267

    Mode Selector Switch

  1. Place the machine in the ROADING MODE.

  1. Place the direction selector switch in the NEUTRAL position.

  1. Place the parking brake switch in the ON position.

  1. Run the engine speed at low idle.

  1. Move the speed selector switch to the speed that is being tested. This will shift the gearshift cylinder that is located on the side of the transmission gearbox.

    Note: Do not depress the accelerator pedal.




    Illustration 4g00916661

    Gearshift Valve

    Valve Removed from Machine for Clarity

  1. Loosen locknut (4) .

  1. Read the pressure on the 8T-0856 Pressure Gauge (0 to 6,000 kPa (0 to 870 psi)) while the following adjustment is being performed.

    The specified pressure for gear engagement is listed in Table 1.

  1. If the pressure is higher than specification, turn adjustment screw (5) counterclockwise in order to lower the pressure.

  1. If the pressure is lower than specification, turn adjustment screw (5) clockwise in order to raise the pressure.

  1. Tighten locknut (4). Ensure that the pressure reading on the gauge is correct.

  1. Move the direction selector switch to the NEUTRAL position and turn off the engine.

  1. Disconnect the test equipment.

Eight Wheel Drive Disengage Pressure Test and Adjust

Testing the Eight Wheel Drive Disengage Pressure

  1. If the eight wheel drive disconnect pressure is not within specifications, follow the procedure below in order to adjust the eight wheel drive disconnect valve.

  1. Start the machine.

  1. Warm the oil in the transmission gearbox and the hydraulic tank to the normal operating temperature.



    Illustration 5g00932267

    Mode Selector Switch

  1. Place the machine in the ROADING MODE.

  1. Ensure that the direction selector switch is in the NEUTRAL position.

  1. Place the parking brake switch in the ON position.

  1. Run the engine speed at low idle.



    Illustration 6g00916614

    Location of the Eight Wheel Drive Disengage Cylinder

  1. Move the eight wheel drive disengage switch to the ON position. This will cause the eight wheel drive disengage valve to shift the eight wheel drive disengage cylinder that is located inside the rear of the transmission gearbox.

    Note: Do not depress the accelerator pedal.

  1. Loosen purge plug (6) slightly in order to purge any air in the system prior to checking the pressure.

  1. Read the pressure on the 8T-0856 Pressure Gauge (0 to 6,000 kPa (0 to 870 psi)) for the eight wheel drive disengage.

    The specified pressure for the eight wheel drive disengage is listed in Table 2.

  1. Turn off the engine.

  1. If the eight wheel drive disengage pressure is within specification, disconnect the test equipment. Adjustment is not necessary. If the eight wheel drive disengage pressure is not within specification, proceed to the section that is entitled "Adjusting the Eight Wheel Drive Disengage Pressure".

Adjusting the Eight Wheel Drive Disengage Pressure

  1. If the eight wheel drive disengage pressure is not within specifications, use the following procedure in order to adjust the eight wheel drive disengage valve.

  1. Start the machine.

  1. Ensure that the hydraulic oil is at the normal operating temperature.



    Illustration 7g00932267

    Mode Selector Switch

  1. Place the machine in the ROADING MODE.

  1. Place the direction selector switch in the NEUTRAL position.

  1. Place the parking brake switch in the ON position.

  1. Run the engine speed at low idle.

  1. Turn the eight wheel drive disengage switch to the ON position. This will shift the eight wheel drive disengage cylinder that is located on the rear of the transmission gearbox.

    Note: Do not depress the accelerator pedal.




    Illustration 8g00916650

    Eight Wheel Drive Disengage Valve

    Valve Removed from Machine for Clarity

  1. Loosen locknut (2) .

  1. Read the pressure on the 8T-0856 Pressure Gauge (0 to 6,000 kPa (0 to 870 psi)) while the following adjustment is being performed.

    The specified pressure for the eight wheel drive disengage is listed in Table 2.

  1. If the pressure is higher than specification, turn adjustment screw (3) counterclockwise in order to lower the pressure.

  1. If the pressure is lower than specification, turn adjustment screw (3) clockwise in order to raise the pressure.

  1. Tighten locknut (2) .

  1. Turn the eight wheel drive disengage switch to the OFF position.

  1. Turn off the engine.

  1. When the eight wheel drive disengage pressure is adjusted correctly, disconnect the test equipment.

Information System:

120H, 12H, 135H, 140H, 143H, 160H and 163H Motor Graders Features
216 and 232 Skid Steer Loaders 3024 Engine Supplement Pump Mounting - Remove and Install
776D, 777D and 777D HAA Off-Highway Truck/Tractors Air System and Brakes Service Brakes and Retarder System Leakage - Check
CB-534D, CB-534D XW and CB-564D Vibratory Asphalt Compactors Propel System Drum Drive Group
CB-634D Paving Compactor Machine Electronic Control System Water Spray Is Always Off
3054E Industrial Engine Engine Oil Filter
793C XQ Off-Highway Truck and 793C Off-Highway Truck Engine Supplement Radiator - Install
561N Pipelayer Plate Locations and Film Locations
120H and 135H Motor Graders Safety Messages
561N Pipelayer Specifications
12H Motor Grader Reference Material
938G Series II Wheel Loader and IT38G Series II Integrated Toolcarrier Steering System Piston Pump (Steering) Margin Pressure - Test and Adjust
776D, 777D and 777D HAA Off-Highway Truck/Tractors Air System and Brakes Service Brakes and Retarder System Pressure - Test
938G Wheel Loader, 938G Series II Wheel Loader, IT38G Integrated Toolcarrier and IT38G Series II Integrated Toolcarrier Traction Control System Proportional Pressure Solenoid Valve - Test
120H, 12H, 135H, 140H, 143H, 160H and 163H Motor Graders Electronic Control Module (Power Train)
CB-534D, CB-534D XW and CB-564D Paving Compactors Machine Systems Radiator and Hydraulic Oil Cooler
Bench Test Procedure for a 784B, 784C, 785, 785B, 785C,785D, 789, and 789B Off-Highway Truck Transmission{3030, 3073}
226 and 242 Skid Steer LoadersEngine Supplement Pump Mounting - Remove and Install
2002/11/11 New Mirror Has Improved Durability and a New Support that Reduces Vibration {7319}
R2900 Load Haul Dump Steering Control
776D, 777D and 777D HAA Off-Highway Truck/Tractors Air System and Brakes Hoist, Torque Converter, and Brake System Troubleshooting
776D, 777D and 777D HAA Off-Highway Truck/Tractors Air System and Brakes Pulled Unit Hydraulics, Torque Converter, and Brake System Troubleshooting
574B Forwarder Power Train Power Train Charge System Pressure - Test
Air Conditioning and Heating R-12 All Caterpillar Machines Machine Preparation for Disassembly and Assembly