CONNECTION 0014223 - Caterpillar

Introduction
The main relief valve for the transmission maintains the maximum pressure of the oil that is delivered to the transmission clutches by the transmission modulating valves. Also, the main 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 limit. The adjustment procedure provides the information that is needed to adjust the main relief valve to the specified limit.Required Tools
Illustration 1 g01291479
Table 1
Required Tools
Item Part Number Part Description Qty
A 6V-7830 Tetragauge group 1 Test Procedure (Transmission Relief Valve)
Illustration 2 g00887535
View of the rear cover of the transmission
Install gauge (A) into pressure tap (P).
Warm the transmission oil to operating temperature.
Run the engine at HIGH IDLE. Note the pressure on the gauge. The pressure should be 3100 150 kPa (450 22 psi).
If the pressure that is observed is not 3100 150 kPa (450 22 psi), perform the steps in "Adjustment Procedure (Transmission Relief Valve)". Adjustment Procedure (Transmission Relief Valve)
Shut off the engine.
Remove cover (1).
Illustration 3 g00932183Note: The main relief valve is located behind cover (1) on the transmission hydraulic control.
Loosen locknut (2).
Turn adjustment screw (3) clockwise in order to increase the pressure setting. Turn adjustment screw (3) counterclockwise in order to decrease the pressure setting. Note: One full turn changes the pressure by approximately 235 kPa (34 psi).Note: Turn adjustment screw (3) counterclockwise past the desired pressure setting. Then, turn adjustment screw (3) clockwise to the correct pressure setting. This method of adjustment eliminates any movement in the threads.
Tighten locknut (2) to a torque of 30 4 N m (22 3 lb ft).
Perform steps in "Test Procedure (Transmission Relief Valve)".