Examination
1. Check the tension of the pump drive belt.
Belt deflection in 98 N:
- New belt - 8-10 mm
- Old belt - 10-15 mm
Note: "New belt" this is a belt that has worked on a running engine for no more than five minutes.
Checking the level of hydraulic booster fluid
1. Park the machine on level ground.
2. Warm fluid up to operating temperature.
With the engine running at 1000 rpm or less, turn the steering wheel a few times in one direction until it stops, then in the other direction to warm up the fluid.
- Liquid temperature - 80°C
3. Check for foaming and emulsification.
Note: Foaming or emulsification indicates air in the system or low fluid level.
4. Check and top up the working fluid in the tank.
- Fluid type: ATF DEXRON or DEXRON II
Note: Check that the fluid level was at the HOT LEVEL mark on the dipstick (hot level). When the engine is cold, the fluid level should be at the COLD LEVEL mark on the dipstick.
Power steering fluid replacement
1. Jack up the front of the machine and support it.
2. Remove the fluid return hose from the system reservoir and drain the fluid into a suitable container.
3. Turn the steering wheel from one extreme position to another while draining the fluid. Stop the engine.
4. Fill the system reservoir with fresh fluid.
5. Start the engine and bring it to idle mode with a crankshaft speed of no more than 1000 rpm.
After 1 or 2 seconds, liquid will begin to pour out through the return hose. At this point, stop the engine immediately.
Warning: Make sure some fluid remains in the reservoir.
6. Repeat steps #4 and #5 four or five times until there is no more air left in the liquid.
7. Connect the return hose to the system tank.
8. Release the air from the power steering system.
Power Steering System Bleeding
1. Check the fluid level in the system reservoir.
Check fluid level and add fluid if necessary.
2. Start the engine and turn the steering wheel from one extreme position to another three or four times when the engine is running at a speed of no more than 1000 rpm.
3. Check that the fluid in the reservoir is not foamy or cloudy and does not rise above the maximum level when the engine is stopped.
Measure the fluid level with the engine running. Stop the engine and check the fluid level again.
- Maximum increase - 5 mm
If the discrepancy is not eliminated, then the steering gear should be repaired.
Fluid pressure test
1. Connect a pressure gauge.
A) Disconnect the pressure line fitting.
b) Connect the pressure gauge with the measurement side to the power steering pump and the valve side to the pressure line.
V) Release the air from the system. Start the engine and turn the steering wheel from one extreme position to another two or three times.
G) Check for correct fluid level.
2. Check that the fluid temperature is at least 80°C.
3. Start the engine and bring it to idle.
4. With the pressure gauge valve closed, take a reading.
- Minimum pressure - 75 kg / cm2
Warning: Do not keep the valve in the closed position for more than 10 seconds. It is not allowed to warm up the working fluid to too high a temperature.
If pressure is low, repair or replace power steering pump.
5. Fully open the valve.
6. Check and read pressure at 1000 rpm.
7. Check and read pressure at 3000 rpm.
Check that the pressure difference at 1000 and 3000 rpm does not exceed 5 kg/cm2.
If the difference is greater, repair or replace the pump flow control valve.
8. Check up indications on pressure at turn of a steering wheel in extreme position.
Make sure the pressure gauge valve is fully open and the engine is idling.
- Minimum pressure - 75 kg / cm2
Warning: Do not hold the steering wheel in the end position for more than 10 seconds. It is not allowed to warm up the working fluid to too high a temperature.
If the pressure is low, the steering gear case has an internal leak and should be repaired or replaced.
9. Measure effort on a steering wheel.
A) With the steering wheel in the middle position, bring the engine to idle.
b) Using a dynamometer, measure the force on the steering wheel in both directions.
- Maximum force on the steering wheel: 5.9 Nm.
If more effort is applied to the steering wheel, repair the power steering assembly.
Note: Before making your diagnosis, you should consider the type of tires, their pressure and contact surface.