SEAL 4524138 - Caterpillar

Adjustment (Boom Cylinder Rod End)
Note: Make sure that the engine speed dial and the power shift pressure for the BOOM DOWN hydraulic circuit is set correctly. Refer to Table 2 for the correct setting.Note: In order to adjust the line relief valve pressure setting for the boom cylinder rod end, a temporary adjustment of the line relief valve for the bucket circuit must be performed. Line relief valve (8) for the bucket is located on top of the main control valve.
Illustration 8 g01201790
Line relief valve (typical example)
(14) Locknut
(15) Adjustment screw
Loosen locknut (14) on the line relief valve for the BUCKET OPEN function. Turn adjustment screw (15) by one half turn in a clockwise direction. Tighten locknut (14) on the line relief valve for the work tool cylinder.
Move the joystick for the work tool to the full BUCKET OPEN position (left). Hold the joystick for the work tool in this position. At the same time, move the joystick for the boom until the boom is at the full BOOM DOWN position (full retraction of boom cylinders). Hold the joystick for the boom in this position.
Check the pressure in the boom cylinder rod end on the pressure gauge at pressure tap (1).
Return the joystick to the NEUTRAL position.
The pressure gauge reading should be 37000 + 2000 - 1000 kPa (5366 + 290 - 145 psi). Refer to Table 2. If the pressure gauge reading at pressure tap (1) is not within the specification, adjust line relief valve (7) that is on the main control valve.
Loosen locknut (14) on the boom line relief valve. Turn adjustment screw (15) until the pressure gauge reading at pressure tap (1) is 37000 + 2000 - 1000 kPa (5366 + 290 - 145 psi). Refer to Table 2. Note: Turn adjustment screw (15) clockwise in order to increase the pressure. Turn adjustment screw (15) counterclockwise in order to decrease the pressure.Note: Always make final pressure adjustment on pressure rise.
Tighten locknut (14) on the boom line relief valve.
After completion of line relief valve adjustment for the boom cylinders, return the line relief valve pressure setting of the bucket to the specified pressure setting. Adjustment (Stick Cylinder)
Note: Make sure that the engine speed dial and the power shift pressure for the STICK OUT hydraulic circuit is set correctly. Refer to Table 2 for the correct setting.
To adjust the line relief valve pressure setting of the stick cylinder rod end, move the joystick for the stick until the stick is at the full STICK OUT position (full retraction of stick cylinder). Hold the joystick for the stick in this position.
Check the pressure in the stick cylinder rod end on the pressure gauge at pressure tap (2).
Return the joystick for the stick to the NEUTRAL position.
The pressure gauge reading should be 38000 + 2000 - 1000 kPa (5511 + 290 - 145 psi). Refer to Table 2. If the pressure gauge reading at pressure tap (2) is not within the specification, adjust line relief valve (12).
In order to adjust line