Hyster Forklift RS46-38L IH

!NOTE: Never remove the safety stand pipe to avoid dirt from entering the hydraulic system.

Engine shut down and parking brake applied

Yellow button on the indicator pressed to release pressure

Cap loosened by turning counterclockwise

Inside of the housing cleaned with solvent

Cap installed by turning clockwise

Engine started and operation of indicator checked

NOTE: Only use plugs that have been cleaned in solvent.

NOTE: In the event that seals are missing, check manifold for missing seals and remove.

NOTE: Cartridge valves are not field serviceable with exception of external seals and electrical solenoids. In event of a defective component, completely replace valve.

NOTE: Check load holding valve for cracks. If there are cracks in load holding valve, the load holding valve must be replaced.

The valve seals are serviceable parts of the load holding valve. Use the following procedures for repair:

Unscrew the cartridge valve from the load holding valve. See Figure 8.

Check that all seals are attached to cartridge valve.

Install a temporary plug in place of cartridge valve.

Sign off on the Derricking Circuit Disassemble

WARNING: Lower boom completely before working on control valve or hydraulic system. The boom can lower suddenly and cause injury if the boom is not lowered.

Is the truck placed on a solid and level surface?

Is the boom lowered and the shutoff valves at the bottom of the hydraulic tank platform closed?

WARNING: Move all control levers back and forth a minimum of 20 times to remove all hydraulic pressure from pilot system.

Are the covers on the topside of the frame removed?

Are tags for identification put on hydraulic lines?

Are the hydraulic lines disconnected from the cab manifold?

Are caps put on the open lines, ports or other connectors?

!WARNING: Lower boom completely before working on control valve or hydraulic system. The boom can lower suddenly and cause injury if the boom is not lowered. This procedure will make sure that the boom cannot lower suddenly and cause injury or death.

!NOTE: All valves and other associated items installed on the load holding valve can be replaced. Before removal of any part, check that the area is clean and protected against dirt and fluid contamination.

Place the truck on a solid and level surface.

Lower boom and close the shutoff valves at the bottom of the hydraulic tank platform.

!WARNING: Move all control levers back and forth a minimum of 20 times to remove all hydraulic pressure from pilot system.

Put tags for identification on electrical wires. Disconnect the electrical wires from the load holding valve.

Put tags for identification on hydraulic lines. Disconnect the hydraulic lines from the load holding valve. Put caps on the open lines, ports or other connectors.

Remove the four capscrews that fasten the load holding valve to the derricking cylinder.

Two methods are given for checking the volume of flow from the hydraulic pump. The first method uses a flow meter, a pressure gauge, and a needle valve. The second method uses a needle valve, a pressure gauge, a container, and a timer.

1. If the flow meter is available, install flow meter between needle valve and outlet port of pump. See Figure 5. Pressure gauge must be between needle valve and pump. Make a separate check for each system.

When hydraulic oil is at operating temperature, run engine at 2100 rpm with no load on hydraulic system. Note reading of flow meter. Compare output rate of pump with specification found in the Specifications section.

!WARNING: Hydraulic oil can be hot. Do not touch oil during tests.

2. Run engine at high limit. Slowly close needle valve until gauge indicates a pressure just below specification for relief valve setting. Pump out- put at high pressure must be within 25% of out- put with no load. If output at high pressure is less than 75% of low pressure output, pump has a problem.

1. Another method of checking pump output is to measure the amount of oil moved in a given amount of time. See Figure 6. Run engine until oil is 55 to 65 C (130 to 150 F).

Disconnect line from outlet port of pump. Install a 0 to 21 MPa (0 to 3050 psi) pressure gauge on a tee fitting connected to a hose from outlet port. Install needle valve on end of hose.