290 Hydraulic System
3. Start the engine and engage the hydraulic pump.
4. Release the body vane pump relief valve.
To adjust the vane pump relief valve, tighten the main relief valve adjustment screw (see
Adjusting Directional Control Valve Pressure on page 290).
5. Disconnect the packer extend proximity switch.
6. Activate the packer extend until it reaches the end of stroke.
7. Adjust the vane pump relief valve according to the pressure chart (see Table 1).
8. Once the vane pump relief valve is adjusted, back out the main relief.
IMPORTANT: When the body and arm vane pump relief valves are adjusted to the proper pressure, adjust the
relief valve on the directional control valve according to the pressure chart (see page 288).
Adjusting Directional Control Valve Pressure
To adjust the pressure:
1. Start the engine and engage the hydraulic system.
2. Install a 0–4000 PSI pressure gauge on the quick-connect coupler located on the hydraulic valve.
Figure 5-33
0–4000 PSI pressure gauge
3. Disconnect the packer extend proximity switch.
4. Activate the packer extend until it reaches the end of stroke.
5. Check the gauge to make sure the pressure is building up in the system.
Warning!
Always make sure the shut-off valve on the suction line is fully open before starting your
truck. Failure to open the shut-off valve may damage the hydraulic system.