SPRING 4505859 - Caterpillar

Adjustment (Boom Cylinder Rod End)
Note: 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.
Loosen locknut (11) on the line relief valve for the BUCKET OPEN function. Turn adjustment screw (12) by one quarter turn in a clockwise direction. Tighten locknut (11) on the line relief valve for the work tool cylinder.
Move the joystick for the work tool to the full BUCKET OPEN position (full retraction of bucket cylinder). 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 38000 + 2000 - 2500 kPa (5511 + 290 - 363 psi). 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 (11) on the boom line relief valve. Turn adjustment screw (12) until the pressure gauge reading at pressure tap (1) is 38000 + 2000 - 2500 kPa (5511 + 290 - 363 psi).Note: Turn adjustment screw (12) clockwise to increase the pressure. Turn adjustment screw (12) counterclockwise to decrease the pressure.Note: Always make final pressure adjustment on pressure rise.
Tighten locknut (11) 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.Note: If an appropriate location is not available to fully extend the boom cylinders, exchange the functions of the boom line relief valves. Remove the line relief valve for the boom cylinder head end and the line relief valve for the boom cylinder rod end from the main control valve. Exchange the location of the line relief valves. Adjust the pressure of the boom line relief valve that is now attached in the head end. After completion of line relief valve adjustment, return the respective line relief valves to the original locations.Adjustment (Stick Cylinder Rod End)
Illustration 7 g01606773
Stick lowering control valve
(11) Locknut
(12) Adjustment screw
(15) Line relief valve (stick cylinder rod end)
Mark the location of adjustment screw (12) on relief valve (15).
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