142 Hydraulic SystemFigure 5-20 Relief valveUsing a ½” Allen key, turn the adjustment screw clockwise to increase pressure or counter-clockwise to reduce pressure.Use a 1½” key to screw/unscrew the locknut.6. Reconnect the packer extend proximity switch.Adjusting the Body Relief Valve (Electro-Hydraulic)To adjust the body relief valve:1. Once the body vane pump relief valve is adjusted, back out the main relief (see F on Figure 5-21).2. Install the pressure gauge at the valve inlet cover (see E on Figure 5-21).3. Disconnect the packer extend proximity switch. Activate the packer extend until it reaches theend of stroke.4. If this is not reading, adjust the utility section of the electric valve (see page 142).5. Set the pressure at idle to 2000 psi for a single axle or to 3000 psi for tandem chassis.Adjusting the Utility Section (Optional Electric Valve only)To adjust the utility section:1. Disconnect the tailgate solenoid.2. Turn on the pump; press the TAILGATE DOWN switch on the control panel.3. Connect a 0–600 psi pressure gauge to the inlet cover (see E on Figure 5-21).4. Back out the generated pilot pressure valve (see A on Figure 5-21) and the pressure reducingvalve (see B on Figure 5-21).5. Disconnect the body-up coil (see C on Figure 5-21).6. With the engine at idle, adjust the generated pilot pressure (see A on Figure 5-21) to 420 psi(± 30 psi) while the Body Up function is activated. The valve adjustment screw is located on theright-hand side of the valve section when facing it.7. Reconnect the body-up coil.LocknutAdjustmentscrew
