PLATE 9V9330 - Caterpillar

Personal injury can result from hydraulic oil pressure and hot oil.Hydraulic oil pressure can remain in the hydraulic system after the engine has been stopped. Serious injury can be caused if this pressure is not released before any service is done on the hydraulic system.Make sure all of the attachments have been lowered, oil is cool before removing any components or lines. Remove the oil filler cap only when the engine is stopped, and the filler cap is cool enough to touch with your bare hand.
Sudden movement or accidental starting of the machine can cause personal injury or death to persons on or near the machine.To prevent personal injury or death, perform the following:Park the machine on a smooth, level surface.Lower the work tool to the ground and engage the parking brake.Stop the engine and remove the key.Block the wheels and install the steering frame lock.
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 Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on Caterpillar products.Dispose of all fluids according to local regulations and mandates.
Table 1
Required Tools    
Part Number     Description     Qty    
8T-5320     Hydraulic Test Group     1    
6V-9508     Plug     1    
6V-8397     O-ring     1    
6V-9829     Cap     2    The pilot diverter solenoid valve is an electrohydraulic valve. The pilot diverter solenoid valve controls the pilot oil pressure to either the tilt control valve spool or the fourth function control valve spool. When the fourth function switch is actuated the pilot diverter solenoid valve supplies pilot oil to the fourth function control valve spool. This procedure will measure the pilot oil pressure that is going to the fourth function control valve spool. This will verify that the pilot diverter valve is operating correctly.
Start the engine. Run the engine at high idle. Operate the control levers and move all the cylinders in order to increase the temperature of the hydraulic oil to normal operating temperature.
Lower the bucket to the ground or onto jack stands. Remove the cover that is over the main control valves in order to access the fourth function valve spool.
Stop the engine.
Move the control levers through the full range of travel several times. This will relieve any pressure that may be present in the implement hydraulic system.
Push on the hydraulic tank breaker relief valve in order to relieve the pressure in the hydraulic oil tank. Push in the plunger until all pressure is released from the hydraulic oil tank.
Illustration 1 g00503284
General Location of the Solenoid Valve and the Fourth Function Control Valve
Illustration 2 g00502959
Main Control Valve Group (Lift and Auxiliary)
Disconnect tube assemblies (1) and (2).
Attach the 8T-5320 Hydraulic Test Group to one of the tube assemblies. Install