RIM AS 8R4877 - Caterpillar

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(22) Axle reverse combination valve
Locate the (reverse) axle combination valve (22) .
Use the following procedure to adjust the combination valve:
Clean the area around the valve of any dirt and contamination.
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Valve Cartridge Assembly (1A) Cap (2A) Backup ring (3A) O-ring
Turn the combination valve cap counter-clockwise 180 degrees to loosen, then turn clockwise approximately 160 degrees. This will help re-seat the O-ring , backup ring, and break loose any paint around the cap. Clean the area again before removing the valve assembly.Note: The combination valve O-ring may be damaged from the treads during installation or removal. If any O-ring material is found, the O-ring must be replaced.
Remove the cap, and combination valve cartridge from the pump. Inspect the O-ring, and backup ring for damage. Inspect the valve and housing threads for possible damage and contamination. Reinstall the cap in order to prevent oil from leaking out the port
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Arrows indicate clamping position.
Clamp the combination valve cartridge in a soft vise jaw. Loosen locking setscrew (23) with a 3 mm Allen wrench.Note: The spring must be compressed in the next step. Turning spindle (24) without the spring being compressed will damage the spindle.
Evenly compress the spring. Use a 5 mm wrench to turn spindle (24) . Turn the spindle clockwise in order to increase pressure. Turn the spindle counterclockwise in order to decrease pressure.Note: One full revolution of spindle (24) changes the pressure setting by approximately 4400 kPa (638 psi).
Tighten locking setscrew (23) .
Remove the combination valve cartridge from the vise.
Remove the cap. Inspect the O-ring, and backup ring for damage. Inspect the valve and housing threads for possible damage and contamination. Install the combination valve cartridge in the pump. .
Reinstall the cap, hand tight. If resistance increases or binding occurs, turn cap counter-clockwise one revolution and then clockwise until tight. this procedure will help to reposition and prevent O-ring damage. Tighten the cap to a torque of 250 N m (185 lb ft). Check for leaks after machine operation.
Repeat Steps 16 through 28.
Disconnect Tool "B" from tap (19) in port "MB". Connect Tool "B" to tap (25) in port "MA".
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Right-hand side view
With the engine start switch in the RUN position and P1STC still connected with the machine, the COR test mode should be displayed; if not repeat Steps 16 through 18 and proceed to the next step.
Move engine start switch (4) to the START position. Release the switch when the engine starts.
Monitor the hydraulic oil temperature with Tool (H) . Operate the machine until the oil temperature reaches 38° C (100° F) minimum.Note: The machine may move in the next step. Make sure that the area around the machine is clear of personnel and obstacles.
Move the parking brake switch to the OFF position.
Select/Click "AXLE COR" in P1STC and the engine RPM should increase to maximum RPM. Watch Tool (A) or Tool (A2) . Needle in Tool (A) should reach a peak and then stabilize at a lower constant pressure while moving the propel lever to the forward