Hydraulic System 151Figure 5-30 Pressure adjustment valuesPressurizing the Tank SystemNOTE: For chassis-mounted tanks only. No pressurization is needed for behind-the-cab mountedtanks; gravity is enough to cause the oil to flow.Cavitation inside the pump generates excessive wear and noise.To prevent cavitation, air pressure inside the hydraulic tank must be set between 3 and 3.5 psi. Agauge and a pressure regulator are installed to adjust air pressure inside the tank. This gauge is locatedinside the frame rail on the curbside of the chassis; it can be accessed only when the body is raised.To adjust the pressure, turn the knob until the pressure reaches 3 to 3.5 psi. The hydraulic tank is alsoequipped with a 5-psi relief valve and a pressurized screw-on filler cap.Danger! Install body safety prop before performing any work under the body.Adjust to1800 psiAdjust to1200 psi Adjust to1200 psiArm horizontal movementArm vertical movementGripperCrusher panel
