MOTOR & MTG GP-TRAVEL 1437993 - Caterpillar

Specifications
Table 1
Implement Pump Standby Pressure
Date Equipment ID Code
Item Specification Actual
Check Standby Pressure at pressure tap (HA). Check pressure at "LOW IDLE". 3000 + 600 - 900 kPa (435 + 87 - 131 psi) Introduction
Implement pump standby pressure is the pressure at the pump discharge port when all implement controls are in the neutral position. Low-pressure standby for the implement pump is not adjustable and the pressure will vary among machines. Low-pressure standby also varies on the same pump over time as leakage in the system increases. Standby pressure will decline as system leakage increases. If significant system leakage is present, standby pressure will equal margin pressure. Standby pressure in some systems is used to provide pilot pressure for controls and valves.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 1 198-4238(1) Pressure Sensor Gp
(0 to 34,450 kPa (0 to 5,000 psi))
T1c 1 198-4236 Adapter Cable As
(1) This sensor must be purchased separately. The sensor is not included in the 198-4240 Digital Pressure Indicator GpReference: 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 extra guidance with preparing the machine for testing, refer to the Testing and Adjusting manual or the Troubleshooting manual for your machine.
Illustration 2 g06309613
Inlet manifold (implement control valve)
(HA) Pump Discharge Pressure tap
(HB) Pressure tap (signal oil)
Install the Tool (T1) on pressure tap (HA).Test Procedure
Remove the operator seat and the floor panel from the machine.
Start the engine and run at minimum rpm. Make sure that the parking brake is fully engaged.
Leave all controls in the HOLD position.
The reading on the Pressure Gauge should be approximately 3000 kPa (435 psi). The reading is the pump pressure output in the low-pressure standby condition.
If the pressure reading is below 2100 kPa (305 psi) or above 3600 kPa (520 psi), refer to "Adjustment Procedure".Adjustment Procedure
Note: Do not adjust the pump output based on the results of the test. If the results are not correct, the Margin Pressure Test should be run.