DRAIN GP-ENGINE OIL 3318144 - Caterpillar

Testing Procedures
Table 1
Required Tools    
Tool     Part Number     Description     Qty    
A     198-4240     Digital Pressure Indicator     1    
B     198-4237     Pressure Sensor Gp (500 PSI)     2    
Illustration 1 g01363262
(1) Rear charge pump (right side) (2) Forward charge pump (left side) (3) Test port for the rear charge pump (4) Rear piston pump (right side) (5) Forward piston pump (left side) (6) Test port for the forward charge pump
Connect pressure sensor (B) onto test ports (3) and (6). Connect pressure sensor (B) to pressure indicator (A). Ensure that pressure indicator (A) is visible from the cab.
Start the engine.
Warm the hydraulic oil to 50 °C to 60 °C (122 °F to 140 °F).
Set the engine speed to low idle. Record the readings from pressure sensors (B) .
Set the engine speed to high idle. Record the readings from the pressure sensors (B) .
Set the engine speed to low idle. Engage the All Wheel Drive (AWD system) at maximum aggression. Shift the machine to "1F". Record the readings from pressure sensors (B) while the machine is being driven.
Set the engine to high idle. Continue driving the machine in "1F". Continue to drive the machine with the AWD system at maximum aggression. Record the readings from pressure sensors (B) .ReferenceRefer to Table 2 for acceptable ranges for the charge pressures.Note: The charge pressure at the front pump is higher than the charge pressure at the rear pump when the AWD system is "OFF". The pressures may be outside of the specified range if this test is performed outside of the prescribed temperature range.
Table 2
AWD Charge Pressure    
AWD State     Engine Speed     Left Hand Charge Pressure     Right Hand Charge Pressure    
        Acceptable Tolerance (200 kPa) (29 psi)    
"OFF"     Low     (1900 kPa) (275 psi)     (2100 kPa) (305 psi)    
"OFF"     High     (2400 kPa) (350 psi)     (2600 kPa) (375 psi)    
"ON", Max Aggression, Operating in "1F"     Low     (1900 kPa) (275 psi)     (1900 kPa) (275 psi)    
"ON", Max Aggression, Operating in "1F"     High     (2400 kPa) (350 psi)     (2400 kPa) (350 psi)    
Stop the machine.
Shift to "NEUTRAL". Disengage the AWD system. Set the parking brake.
Shut down the machine.
Perform the following steps if the following conditions occur: low charge pressure for either pump and no increase in the charge pressure with the increase in the engine speed, perform the following steps:
Replace the AWD charge filters.
Check for restrictions in the lines for the charge filter.
Replace the cold start valve in the charge pump.
Replace the charge pump.
The Testing and Adjusting, "Piston Motor Case Drain Flow - Test" should be accomplished if other symptoms occur.Diagnostics
Low charge pressure and high flushing flow is recorded.
This indicates one of the following:
The motor is worn.
The flushing valve in the motor has failed.
Replace the motor for either symptom.
The following items are recorded: low charge pressure, low