RING-PISTON 2848993 - Caterpillar

Pressure Compensator Adjustment
Adjustment Procedure
Illustration 6 g00903590
View on the left side of the machine (1) Test fitting for the load signal
Illustration 7 g01001801
(7) Cap nut (8) Adjustment screw (9) Locknut (10) SealNote: Make this adjustment only after trying to make the adjustment of the load sensing valve first.
Do not remove Tooling (B) . Operate the engine at low idle.
Remove cap nut (7) and seal (10) .
Loosen locknut (9) .
Turn adjusting screw (8) counterclockwise in order to reduce the setting of the pressure compensator. Turn the screw until the margin pressure begins to drop.
When the margin pressure begins to drop, turn adjusting screw (8) clockwise by a 1/4 turn. This ensures that the pressure compensator is set above the adjustment for the relief valve (load sensing oil).
Tighten locknut (9) while you hold screw (8) in place.
Install seal (10) and cap nut (7) .
Stop the engine and remove Tooling (B) from the machine.Low Pressure Standby Test
Introduction
When the machine is not being steered and all implement controls are in HOLD, the piston pump should operate in low pressure standby. The pump output pressure is at a minimum in low pressure standby.Reference: See Systems Operation/Testing and Adjusting, "Location of Hydraulic Components" for the location of the hydraulic components on the machine.Required Tools
Use the following test equipment in order to perform the following procedure:
Appropriate pressure gaugesTable 5 provides a list of required tools if pressure gauges will be used to perform the following test procedure.
Table 4
Required Tools    
Tool     Part Number     Part Description     Qty    
A     6V-7830     Pressure Gauge     1    Note: Ensure the use of 6V-7830 Pressure Gauge . During engine start-up, a 17250 kPa (2500 psi) pressure spike is possible.Test Procedure
Personal injury can result from removing hoses or fittings in a system under pressure.Failure to relieve pressure can cause personal injury.Do not remove or disconnect hoses or fittings until all pressure in the hydraulic system has been relieved.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
Ensure that the hydraulic oil is warm. Refer to Machine Systems Troubleshooting, RENR5195, "Machine Preparation for Troubleshooting" for further information.
Retract the boom and lower the boom. Ensure that the frame is level.
Stop the engine. Turn the steering wheel in both directions. This procedure helps purge pressure from the hydraulic system.
Connect Tooling (A) to test fitting (2) . Refer to Illustration 2.Note: Ensure the use of 6V-7830 Pressure Gauge . During engine start-up, a 17250 kPa (2500 psi) pressure spike is possible.
Start the engine and operate the engine at low idle. Do not turn the steering wheel and do not operate the implement controls. The output pressure