NIPPLE-PIPE 0058615 - Caterpillar

The relief valve is part of the control valve. The control valve is below the level of the oil in the hydraulic tank. When an adjustment is needed for the relief valve, hydraulic oil must be drained from the tank.Relief Valve Test
Lower the body and stop the engine. After the engine stops, move the control lever to RAISE and LOWER positions, then put the lever in the FLOAT position.
LOCATION FOR RELIEF VALVE TEST (CAPS SHOWN OVER QUICK DISCONNECT NIPPLES)
1. Hoist cylinder (left). 2. Quick disconnect nipple (for pressure during RAISE). 3. Quick disconnect nipple (for pressure during LOWER).Connect a hose assembly with a 28 000 kPa (4000 psi) pressure gauge to the quick disconnect nipple assembly (2) on the rod end of hoist cylinder (1).Start the engine and lift and lower the body many times to get the temperature of the hydraulic oil to more than 38°C (100°F).Run the engine at high idle speed and move the control lever to the RAISE position. After the body has been lifted to dump position, look at the gauge and move the control lever and hold it in the RAISE position. The high indication on the gauge is the pressure setting of the relief valve. The correct setting for the relief valve is 15 370 170 kPa (2225 25 psi).Adjustment for Relief Valve
Start and run the engine and move the control lever to the FLOAT position for approximately 20 seconds. Stop the engine.
COVER ON REAR OF HYDRAULIC TANK
COVER REMOVED FROM TANK
1. PlugDrain the oil from the hydraulic tank until the oil is below the cover of the tank. Remove the cover.Remove plug (1) and adjust as follows: To increase pressure setting either add shims (2) in plug (1) or remove shims (4) from under plug (1).To decrease pressure setting either remove shims (2) from inside plug (1) or add shims (4) to plug (1).Pilot valve spring (5) and pilot valve (3) must be in position when plug (1) and he shims are installed on the relief valve. The torque for plug (1) is 108 7 N m (80 5 lb. ft.)
6J3400 RELIEF VALVE
1. Plug. 2. Shims. 3. Pilot valve. 4. Shims. 5. Pilot valve spring. Fill Oil Tank Procedure
Make reference to on first page of HYDRAULIC SYSTEM TESTING AND ADJUSTING section.
Use two different oils when filling or adding to the hydraulic tank. Use SAE 30 when filling the transmission oil tank and SAE 10W when filling the hydraulic oil tank.
1. Put the oil in hydraulic tank until the oil can be seen in the gauge.2. Start and run the engine at low idle rpm. With the engine running, add oil to the tank to keep the level of the oil in the gauge.3. When no more oil is needed to keep oil in the gauge, raise