ELBOW 0007444 - Caterpillar

Hydraulic oil pressure can remain in the hydraulic system on this machine after the engine and pump have been stopped. Serious injury can result if this pressure is not released before any service is done on the hydraulic systems. In order to prevent possible injury, release the hydraulic system pressure before working on any fitting, hose, or hydraulic component.Lower all attachments to the ground before service is started. If the hydraulic system must be serviced, tested, or adjusted with the attachment in the raised position, the attachments and lift cylinders must be supported properly.Always move the machine to a location away from the travel of other machines. Be sure that other personnel are not near the machine when the engine is running and tests or adjustments are being made.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Dispose of all fluids according to local regulations and mandates.
Use the following procedure in order to check the pressure setting for the torque converter inlet relief valve.Introduction
The torque converter inlet relief valve limits the maximum pressure to the torque converter section of the torque divider. The torque converter inlet relief valve also prevents damage to the torque converter when the engine is started and the oil is cold. The following test will check the maximum pressure of the oil that is delivered to the torque converter section of the torque divider.Required Tools
Illustration 1 g01089423
Tooling (A)
Table 1
Required Tools    
Tooling    Item    Part
Number    Description    Qty    
A     A1     8T-0855     Pressure Gauge
0 to 4000 kPa (0 to 580 psi)     1    
A2 6V-3989     Fitting     1    
A3 6V-4143     Coupler     2    
A4 177-7861     Hose As
0 to 6000 kPa (0 to 870 psi)     1    Test Procedure (Torque Converter Inlet Relief Valve)
Move the machine to a smooth horizontal location.
Lower all of the implements. Engage the parking brake. Turn the engine OFF.
Illustration 2 g01195176
The pressure tap for the torque converter inlet relief valve is located behind the access door on the right fender of the machine. (M) Pressure Tap for the Torque Converter Inlet (N) Pressure Tap for the Torque Converter Outlet
Attach tooling (A) to pressure tap (M) .
Start the engine. Do not warm the hydraulic oil.
Operate the engine starting at LOW IDLE (800 rpm) and slowly increase the speed. Make sure that the steering control lever is in the NEUTRAL position.
Watch the pressure at tooling (A). The pressure should rise with the engine speed until the pressure reaches 900 kPa (130 psi).
The torque converter inlet relief valve is not adjustable. If the pressure continues to rise above 900 kPa (130 psi), replace the relief valve.Note: The torque converter inlet relief valve is located under the lubrication distribution manifold.Note: The torque converter inlet relief valve is not adjustable. If