Hot oil and hot components can cause personal injury. Do not allow hot oil or hot components to contact skin.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.
Refer to Special Publication, NENG2500, "AVSpare Tools and Shop Products Guide" for tools and supplies suitable to collect and contain fluids on AVSpare products.
Dispose of all fluids according to local regulations and mandates.
|Required Tools    |
|Part Number    ||Description    ||Qty    |
|4C-4890    ||Hydraulic Test Group    ||1    |
|8T-5320    ||Hydraulic Test Group    ||1    |
The maximum pressure in the steering system is limited to 22800 ± 350 kPa (3305 ± 50 psi) by the pump control section (pressure and flow compensator valve) of the steering/pilot pump.
Fully articulate the machine in order to achieve a stall condition. Maintain force on the steering wheel in order to achieve maximum pressure in the steering/pilot pump.
Use the following procedure in order to determine whether the steering pressure is being regulated correctly by the control section of the steering/pilot pump:
- Install the steering frame lock.
Steering Frame Lock
- Install a 27000 kPa (4000 psi) pressure gauge at pressure tap (1) .
Cab has been removed for photographic clarity.
(1) Pressure tap.
- Start the engine and run the engine at low idle. Allow the hydraulic oil to reach normal operating temperature.
- Now, operate the engine at high idle and turn the steering wheel against the steering frame lock.
- Note the reading on the pressure gauge. The reading should be 22800 ± 350 kPa (3305 ± 50 psi).
Rubber Stop Pad
Note: If the steering frame lock cannot be used, turn the steering wheel so that the machine is fully articulated. Continue to turn the steering wheel against the rubber stop pads on the frames.
- Stop the engine and remove the pressure gauge from the pressure tap.
Note: Do not keep the steering/pilot pump at stall condition for more than ten seconds. If necessary, release the steering wheel and wait for 30 seconds before you repeat the procedure.
Reference: For the correct test procedure, refer to Testing and Adjusting, " Piston Pump (Steering) Margin Pressure - Test and Adjust".