FUEL SYSTEM 5P9338 - 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 work tools have been lowered to the ground, and the 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.
To prevent personal injury when checks are made while the machine is in operation, make sure only approved personnel are on the machine. Keep other personnel off the machine and in view of the operator. Make sure checks are done in an open area.
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     Quantity    
198-4240     Digital Pressure Indicator     1    
Prepare the machine for adjustment.Reference: Testing and Adjusting, "Preparation for Troubleshooting".Note: Position the pressure gauge and the hydraulic lines in order to prevent damage from any moving components on the machine. Position the test equipment in order to allow either a second technician or the operator that is in the cab to observe the test equipment.
Illustration 1 g00921645
Remove the bolt and the nut from transport pin (1). Remove transport pin (1). Ensure that transport guard (2) is installed on the felling head.
Warm the hydraulic oil to normal operating temperature. Normal operating temperature is 45 °C (115 °F) to 70 °C (160 °F). Use the following procedure in order to warm the hydraulic oil.
Operate the engine at 1800 RPM to 2000 RPM.
Extend the lift arms until the cylinders bottom out.
Operate the tilt cylinders back and forth until you reach the normal operating temperature.
Attach the 198-4240 Digital Pressure Indicator to the proper pressure tap for the function that is being operated.
Do not hold any function in the stalled position for more than 10 seconds. Hydraulic oil is heated very rapidly when the oil is forced over the relief valve. Component damage could result.
Actuate the function until the function is in the stalled state. Record the pressure on the pressure gauge while the function is stalled.
Operate each function of the felling head.
Grapple arms
Accumulator arms
The pressure that is recorded should correspond with the pressure for the machine that is listed in Table 2.
Table 2
Line Relief Valve Pressures    
Function     Position     Pressure    
Grapple Arms     OPEN    
27600 kPa (4000 psi)    
CLOSE
Accumulator Arms     OPEN    
CLOSE Note: If the pressure