CYLINDER AS 5578469 - Caterpillar

Adjustment Procedures
Table 2
Required Tools    
Part Number     Description     Qty    
6V-2100     Multitach group     1    
6V-4161     Hydraulic testing group     1    
8T-0470     Thermometer group     1    
Table 3
Relief Valves    Pressure change with One Turn Of Adjustment Screw    
Main implement valves    
21600 kPa (3150 psi)    
Main travel valve    
28400 kPa (4100 psi)    
Line relief valve    
17700 kPa (2550 psi)    
Swing relief valve    
1225 kPa (180 psi)    
Relief valve for swing boom and blade control valve    
15700 kPa (2300 psi)    
Relief valve for blade cylinder    
17700 kPa (2550 psi)    
Pilot relief valve    
675 kPa (98 psi)    
Line relief valve (swing boom)    
7700 kPa (1100 psi)    Note: Pressure specifications in Table 3 are approximate values. Use a pressure gauge for adjustment.Preparation For Relief Valve Adjustment
Illustration 2 g00467147
Pump Compartment (1) Pressure tap (right pump delivery pressure) (2) Pressure tap (left pump delivery 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 either pressure tap (1) or pressure tap (2) .
Start the engine.
Extend and retract the stick cylinder several times in order to increase the hydraulic oil temperature to 55° 5°C (131° 9°F).
Place the machine controls at the following settings: Power Mode Switch OFF and engine speed dial in the HIGH IDLE position.ReferenceMake reference to Testing And Adjusting, "Operational Checks" for engine rpm settings.Note: Normal operations of the engine and pumps are necessary for the pressure adjustments. If the results of the pressure adjustment are not correct, then the engine and the pump characteristic curve needs to be checked. Slow output flow from the pump is an indication of air in the hydraulic system. Make sure that no air is present in the hydraulic system. Refer to Testing And Adjusting, "Hydraulic System Pressure - Release".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 g00392871
Top of main control valve (3) Plug (4) Hose (5) Locknut (6) Plug (7) Locknut (8) Main relief valve
Position the machine on level ground.
Stop the engine.
Disconnect hose (4) from main relief valve (8) .
Install 9S-5518 Plug in the open end of hose (4) .
Install 9L-8493 Cap on the opening of main relief valve (8) .
Slowly move the bucket control lever to the BUCKET OPEN position (full retraction of the bucket cylinder rod).
Be sure that the main relief valve pressure is set at 27500 490 kPa (4000 72 psi).Note: Always make final pressure adjustments on pressure rise.
Loosen locknut (7). Turn plug (6) clockwise for one quarter turn. The pressure gauge reading at pressure tap (1) or pressure tap (2) should be 33300 kPa (4850 psi).
Tighten locknut (7) .Note: Turning plug (6) clockwise increases the pressure. Turning plug (6) counterclockwise decreases the pressure.