PUMP GP*R 7X8050 - Caterpillar

Rework Procedure
BEFORE ACCESSING MAIN CONTROL VALVE
Prior to performing this rework procedure, it will be necessary to become familiar with Service Publication, RENR8881. This publication, located in Caterpillar SIS-Web, contains important information required to safely access the main implement control valve.
1. Park the machine on flat, level surface away from traffic.
2. Install the steering frame lock.
(Refer to RENR8881 "Steering Frame Lock-Separate and Connect")
3. Access the main implement control valve by raising the boom arms, dumping bucket, and properly supporting the boom.
(Refer to RENR8881 "Main Control Valve & Mounting Plate-Remove")
4. Release all hydraulic pressure.
(Refer to RENR8881 "System Pressure-Release")
5. Clean area immediately surrounding the main implement control valve to prevent potential hydraulic contamination.
CROSS TORQUE/TURN PROCEDURE
(See Image 1.1.1, Cross Torque/Turn Sequence)
This rework procedure involves a process called "Torque and Turn". This procedure is required to assure that the proper clamping force is applied to the function blocks of the M3PC Main Implement Control Valve.
In applying this rework procedure it will be necessary to replace each tie rod and apply 50 Nm torque utilizing a "Back Up" wrench on the opposite nut. Each tie rod should be replaced and tightened to the proper torque before moving on to the next tie rod. The replacement of the tie rods should be performed in a "Cross Torque" fashion (See Image 1.1.1, Cross Torque Sequence), replacing in the order of "A", "B", "C", and then "D". After all four tie rods have been replaced, it will then be required to turn each nut 180 Degrees in a tightening fashion. This also will have to be done following the prescribed "Cross Torque" sequence. In order to insure that the opposite nut does not turn during this procedure, a "Back Up" wrench will once again be required. In order to verify the proper turning procedure, it will be necessary to mark the nut which is being turned in reference to the valve body and at 180 Degrees. It is also necessary to mark the nut being "Backed Up" in reference to the valve body. When the procedure is completed for each tie rod, these reference markings should be checked in order to verify that the nut was in fact tightened an additional 180 Degrees and that the "Back Up" nut has not rotated. If the "Back Up" nut has rotated, then the nut being rotated will require additional rotation by the corresponding amount.
Image1.1.1
REMOVE PILOT ACCUMULATOR AND FILTER TUBES
(See Image 1.2.1, Pilot Accumulator Tube Removal).
Image1.2.1
1. Remove the pilot accumulator tube and test fitting.
2. Remove the filter tube.
3. Install 6V-9829 Caps and 6V-9508 Plugs with 6V-8397 Seals on the tube connections and ports to minimize risk of contamination.
TIE ROD REPLACEMENT AND CROSS PRE-TORQUE PROCEDURE
All tie rod studs on 966H an 972H (2-Function) Machines can be removed from the front frame of the machine.
1. Remove Tie Rod Stud "A" and discard tie rod, nuts and washers.
2. Install new 238-1975 Tie Rod Stud, 9X-8257 Washers and 8T-4132 Nuts.
3. Utilizing a "Back-Up" wrench, pre-torque Tie Rod "A" to 50 Nm torque.
4. Repeat Steps 1-3 for Tie Rod Nuts B, C, and D in sequential order.
POST