PUMP GP 1661006 - Caterpillar

Specification
Table 1
Cutoff Pressure
Date Equipment ID Code
Item Specification Actual
Cutoff Pressure 26200 500 kPa (3800 73 psi) Introduction
Cutoff Pressure is the maximum pressure that can exist in the implement hydraulic system before the relief valve opens. A low cutoff pressure setting can decrease performance of the implements. A high cutoff pressure could damage components. Use the following procedures to test or adjust the cutoff pressure.Required Tools
Illustration 1 g06221007
Tooling (T1) 198-4240 Digital Pressure Indicator Gp
Table 2
Required Tools
Tool Item Qty Part No Description
T1 198-4240 Digital Pressure Indicator Gp
T1a 1 198-4234 Digital Indicator
T1b 1 251-9600(1) Pressure Sensor Gp
(0 to 68,900 kPa (0 to 10,000 psi))
T1c 1 198-4236 Adapter Cable As
(1) This sensor can only be used on large diameter pressure taps like 6V-3965 Fitting.Reference: Refer to Tool Operating Manual, NEHS0818, "Using the 198-4240 Digital Pressure Indicator Group" for more information on using Tooling (T1).Test Preparation
Move the machine to a flat open area.
Lower all implements to the ground.
Stop the engine.
Turn the key to the ON position, but do not start the engine.
Verify that the implement shutoff control is in the UNLOCKED position.
Move the implement control levers and the transmission control lever through the full range of travel several times. This movement should relieve any pressure that may be present in the implement hydraulic system and the power train system.
Make sure that the pressure in the entire hydraulic system has been released.Reference: For guidance with preparing the machine for testing, refer to the Testing and Adjusting manual or the Troubleshooting manual for your machine.
Remove floor plate in front of seat.
Illustration 2 g06309613
Inlet manifold (implement control valve)
(HA) Pump Discharge pressure tap
(HB) Pump Signal pressure tap
Install Tool (T1) to pressure tap (HA).Test Procedure
Start the engine and run at HIGH IDLE.
With the engine at HIGH IDLE, move the ripper tip control lever to the maximum RETRACT position. After the cylinder is at the end of the stroke, the implement pump is at the stall condition.Note: For machines that are not equipped with a ripper, blocking plates may be used on the hoses for the bulldozer lift circuit for the test.Note: Do not hold the machine in the implement stall condition for more than 15 seconds at a time.
The pressure reading on Tool (T1a) should be 26200 500 kPa (3800 75 psi).
If the maximum pressure is too high or too low, the pressure cutoff needs adjusted. Refer to "Adjustment Procedure"Adjustment Procedure
Illustration 3 g00491586
Implement Pump Pressure Compensator Valve
(1) Screw
(2) Locknut
(3) Margin spool
(4) Screw
(5) Locknut
(6) Pressure cut off spool
Illustration 4 g00527724
Pressure Compensator Valve
(3) Margin spool
(6) Pressure cut off spoolIf an adjustment to the pressure cutoff spool is required, use the following procedure:
Lower all implements to the ground.
Shut off the engine and move all the implement control levers to release the system pressure.
Hold screw (4) with a hex wrench and loosen locknut (5) with a combination wrench. Turn screw (4) counterclockwise to decrease the pressure setting and turn the screw clockwise to increase the setting.
When the pressure setting is adjusted,