ALTERNATOR GP 3416271 - Caterpillar

Table 1
"Relief Valve (Main) - Test and Adjust"    
Date     Machine Serial Number    
Machine Settings     Engine Speed    
Speed Dial "10"
AEC switch OFF
Item     Specification     Actual    
Main Relief     35000 + 500 - 1000 kPa (5076 + 73 - 145 psi)        
Position the machine on level ground and stop the engine.
Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release".
Illustration 1 g01221037
Pump compartment (1) Pressure tap (delivery pressure for drive pump) (2) Pressure tap (delivery pressure for idler pump) (3) Pressure tap (power shift pressure)
Attach a 60000 kPa (8700 psi) pressure gauge to pressure tap (1) .
Start the engine.
Place the machine controls at the following settings: Engine speed dial "10" and AEC switch OFF.ReferenceMake reference to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for engine rpm settings.
Increase the hydraulic oil temperature to 55° 5°C (131° 9°F).
Open the bucket until the bucket cylinder rod is at the full retraction.
Check the main relief valve pressure setting at pressure tap (1) .
Illustration 2 g01241266
Top of main control valve (4) Adjustment screw (5) Locknut (6) Main relief valve
Return the control lever to the NEUTRAL position. Adjust the main relief valve pressure to 35000 + 500 - 1000 kPa (5076 + 73 - 145 psi).
To adjust the main relief valve pressure, loosen locknut (5) and turn adjustment screw (4) until the pressure gauge reading at pressure tap (1) is 35000 + 500 - 1000 kPa (5076 + 73 - 145 psi).
Tighten locknut (5) to a torque of 50 10 N m (37 7 lb ft).Note: Turning adjustment screw (4) clockwise increases the pressure. Turning adjustment screw (4) counterclockwise decreases the pressure.Note: Always make final pressure adjustments on pressure rise.Temporary Setting of the Main Relief Valve
Note: A temporary setting of the main relief valve is required before any line relief valve can be adjusted.
Illustration 3 g01221037
Pump compartment (1) Pressure tap (delivery pressure for drive pump) (2) Pressure tap (delivery pressure for idler pump) (3) Pressure tap (power shift pressure)
Position the machine on level ground.
Stop the engine.
Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release".
Connect a 60000 kPa (8700 psi) pressure gauge to pressure tap (1) .
Start the engine.
Increase the hydraulic oil temperature to 55° 5°C (131° 9°F).
Place the machine controls at the following settings: Engine speed dial "10" and AEC switch OFF.ReferenceMake reference to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for engine rpm settings.
Open the bucket until the bucket cylinder rod is at the full retraction.
Check the main relief valve pressure setting at pressure tap (1) .
Illustration 4 g01241266
Top of main control valve (4) Adjustment screw (5) Locknut (6) Main relief valve
Be sure that the main relief valve pressure is set at 35000 + 500 - 1000 kPa (5076 + 73 - 145 psi).Note: Always make final pressure adjustments on pressure rise.
Loosen locknut (5) . Turn adjustment screw (4) clockwise