Checking Operation of Power Steering With H-31 System
CHECKING OPERATION OF POWER STEERINGH-31 SYSTEM
- Engine At Operating Temperature -
Check hydraulic fluid level in tank. Check all hate connections and equipment (pump, brake booster, power flow regulator and steering gear) for leaks before checking operation.
Discharge Pressure:
Operate brake pedal about 20 times with engine stopped.
Instill pressure tester 32 4 000 between pump and power flow regulator.
1. = Power flow regulator or steering gear connection.
2. = Pump connection
A = Shut off value (low pressure: 0 to 15 bar or 0 to 213psi).
Caution!
Shut off value (A) must always be closed for high pressure tester to avoid damaging pressure tester.
B = Shut off value (high pressure: 0 to 150 bar or 0 to 2133 psi).
Open value (B).
Close valve (A).
Start engine - fill hydraulic fluid in tank.
Bleeding System:
Turn steering wheel two times each againest left and right lock.
Operate brake pedal 5 times, wait 30 seconds and operate pedal another 5 times. Hydraulic fluid temperature should be approx. 55°C (122°F) for all tests.
Turning steering wheel against locks with engine running could cause a rise in temperature.
1. Checking Flow Pressure:
Open valve (B).
Close valve (A) and run engine.
Open valve (A) and read pressure when pressure is less than 15 bar (213 psi).
Max. permissible flow pressure of 8 bar (114 psi) must not be exceeded.
Pressure Greater Than 8 Bar (114 psi):
2. Checking Pump:
Install pressure taster between pump and power flow regulator.
Close valve (A). Start engine.
Close valve (B) max. 10 seconds and read pressure.
Rated pump pressure ± 10 % should be reached.
Rated pressure exceeded replace pump
Rated pressure not reached, check drive belt tightness.
Repeat pressure still not reached, replace pump.
3. Checking Reservoir Charging Pressure:
Pressure tester between pump and power flow regulator.
System bled.
Engine not started.
Valve (B) open.
Valve (A) closed.
Start engine and observe pressure tester. Pressure must rise to max. 57 bar (811 psi) and then drop immediately to less than 8 bar (114 psi).
If max. permissible pressure of 57 bar (811 psi) is exceeded or there is no immediate pressure drop after reaching the maximum permissible pressure, replace power flow regulator.
4. Power Steering:
Pressure tester between pump and power flow regulator.
System bled.
Valve (B) open.
Valve (A) closed.
Engine not started.
Lift car.
Stop steering from reaching final left lock by 1/2 to 3/4 steering wheel turn with a piece of wood or something similar,
Start engine.
Pull steering wheel against final left lock with a force of force of 100 N (22 lbs.) (force meter) about 5 seconds and read pressure.
Limit final right lock and repeat test on right lock.
If pressure values are lower than pump pressure determined in point 2, replace steering gear.
5. Checking Mechanical Play of Steering.
- Pressure point adjusted.
- No play in steering column.
Pressure taster between pump and power flow regulator.
System bled.
Valve (B) open.
Valve (A) Closed.
Engine not started.
Steering drop arm held in straight ahead position with Special Tool 32 4 060.
Paste strips of paper on the steering wheel hub and casing upper Section.
Make mark (center) on steering wheel hub.
Start engine:
Open valve (A).
Read flow pressure.
Turn steering wheel counterclockwise until pressure tester shows 1 bar (14 psi) more pressure than the flow pressure value. Mark position of steering wheel hub Repeat this in clockwise direction If max. permissible travel (C) = 7 mm (0.276") is exceeded, replace the Steering gear.
Remove special tool holder and pressure tester. Bleed hydraulic system and, if necessary. add hydraulic fluid.