COUPLING GP 1862989 - Caterpillar

Specifications
Table 1
Pressure Test for the Transmission Main Relief Valve
Date
- Product or Component SN
-
Item Specification Actual
Engine speed Low Idle
LOW IDLE at pressure port (P1) 2585 105 kPa (375 15 psi)
Pressure at clutch 5 2250 170 kPa (325 25 psi) Introduction
The transmission relief valve maintains the maximum pressure of the power train oil that is delivered to the transmission clutches by the transmission modulating valves. Also, the transmission relief valve protects the transmission hydraulic system from any high-pressure spikes.The following test procedure will verify whether the pressure setting is within the specified limits. The adjustment procedure provides the information that is needed to adjust the transmission relief valve to the specified value. The pressure setting of the transmission relief valve should be set with the engine at LOW IDLE.Required Tools
Illustration 1 g02571852
Tooling (A) 198-4240 Digital Pressure Indicator Gp
Table 2
Required Tools
Tool Item Qty Part No Description
A 198-4240 Digital Pressure Indicator Gp
A1 1 198-4234 Digital Indicator
A2 1 198-4237 Pressure Sensor Gp
(0 to 3,445 kPa (0 to 500 psi))
A3 1 198-4236 Adapter Cable As Test Preparation
Move the machine to a smooth horizontal location.
Place the steering control lever in the NEUTRAL position.
Engage the parking brake.
Illustration 2 g03806701
Verify that the bolt and washer are removed from location (1) on the counterweight frame and stored properly in the block indicated in illustration 2.
Extend the counterweight approximately 30.5 cm (12 inch).
Stop the engine.
Turn the key to the ON position, but do not start the engine.
Verify that the implement lockout switch is in the UNLOCKED position.
Move the thumb rocker for the counterweight control to the EXTEND position. The counterweight should move outward to the neutral position.
Move all hydraulic controls through all positions in order to relieve hydraulic pressure. Repeat this step until all hydraulic pressure is released. This procedure should relieve any pressure that may be present in the implement hydraulic system.
Illustration 3 g03811788
Attach Tooling (A) to test port (P1) on the rear of the transmission housing. Test Procedure
Start the engine. Warm the power train oil to a temperature of 84° 8°C (183° 14°F).
Operate the engine at LOW IDLE.
Ensure that the transmission is in NEUTRAL.
Disengage the parking brake.
Check the pressure at tooling (A). The pressure at tooling (A) should be 2585 105 kPa (375 15 psi).
If the pressure at tooling (A) is not within the specified limits, perform the following adjustment procedure. Adjustment Procedure
Illustration 4 g03815255
(2) Cover
(3) Bolts
The transmission relief valve is located behind cover (2).
Loosen and remove bolts (3).
Remove cover (2).
Illustration 5 g03811959
(4) Relief valve
(5) Locknut
(6) Adjustment screw
Loosen locknut (5) on relief valve (4). Maintain the position of adjustment screw (6). Note: One turn of the adjustment screw changes the relief valve setting by 235 kPa (34 psi).
Turn adjustment screw (6) clockwise in order to increase the relief pressure. Turn adjustment screw (6) counterclockwise in order to decrease the relief pressure.
After the pressure is adjusted within the specified limit, tighten locknut (5). Make sure that you hold adjustment screw (6) in