SOCKET-16 MM 5531199 - Caterpillar

1-2 Equipment Arrangement
1-3 Pressure Adjustment Flow Chart
Main relief pressure, Overload relief pressure, Crossover relief pressure 1-4 Adjustment Preparation
(1) Release of internal pressure from hydraulic system 1. Place the machine on a level ground and stop the engine. Activate all control levers in all directions to release internal pressure from the hydraulic lines.(2) Release of air from hydraulic tank 1. Remove the bolts and loosen the cap protector so that the air breather cap can be turned.2. Slowly turn the air breather cap counterclockwise to release air from the hydraulic tank.(3) Disconnection of boom control rod from control valve (B) 1. Pull out the split pin from the clevis pin with a pliers.2. Pull out the clevis pin from the rod.3. Disconnect the rod from the control valve (B).(4) Installation of pressure gauge 1. Clean the pressure gauge installing area.2. Remove the plug from the delivery line.3. Install the connector to the delivery line.4. Connect the flexible hose of the pressure gauge to the connector. * The photo at the left shows the control valve A side.* The photo at the right shows the control valve B side.(5) Checking engine speed 1. Install the engine tachometer detector to the fuel injection line of the engine No.1 cylinder.2. Run the engine at low idle until the water temperature gauge registers the green zone.3. Move the accelerator lever fully backward and be sure that the engine speed reaches 1900 rpm or more.(6) Oil level check in hydraulic tank 1. To check oil level; Place the machine on a level ground. Fully extend the arm and bucket cylinders, lower the bucket to the ground and stop the engine.2. The oil level should be within the low temperature range 1. in ambient temperature [10 to 30°C (50 to 86°F)] or within the high temperature range 2. in normal operating condition. If below the specified level, add hydraulic oil to the hydraulic tank.(7) Setting of hydraulic oil temperature to specified level Perform engine warm-up operation, referring to the operation manual. 1. Check to be sure that the hydraulic oil temperature reaches 50 5°C (122 41°F) using a digital thermometer. * After engine warm-up operation, the water temperature gauge should register the green zone.* Improper temperature oil can not offer any actual pressure measurements. Too low temperature oil will give higher pressure measurements than actual and vice versa.1-5 Adjustment Procedure
* If a measured pressure differs from the specified pressure by 10 kgf/cm2 (142 psi) or more, check to see that the pressure gauge is functioning correctly.* Proper pressure adjustment can be made only when engine output and speed, and pump delivery flow are normal. If still not satisfactory after completion of pressure adjustment, it is necessary to check the pump and engine again.* 1/4 turn of the adjusting screw in the main relief valve will change the pressure approx. 40 kgf/cm2 (569 psi).1-5-1 Control valve A(1) Temporary set of main relief pressure 1. Operate the bucket cylinder to the full retraction position and