Test and Assembly Work on Power Steering

General
Damage to the power steering is caused by a shortage of oil in the hydraulic system. Even small leaks can cause the fluid to escape and damage the servo pump as a result of the high oil pressure occurring in the hydraulic circuit.
"Grunt-like" noises when the steering is locked or foam formation in the reservoir indicates a shortage of oil and/or that air has also been sucked in. Before filling the reservoir, any existing leaks must be eliminated on the suction side. Alternatively, the defective part on the pressure side should be replaced.





Power steering and clutch operation are supported by hydraulic auxiliary forces. The common reservoir -A- is located in the engine compartment.
Only Pentosin CHF 11 S may be filled into the reservoir.

Note:
- There is a second tank in the luggage compartment for clutch operation. This container is located under a cover.
- Rack-and-pinion steering gear and servo pump must not be repaired or dismantled.

Checking Hydraulic Fluid Of Power Steering And Servo Clutch

Note:
- Power steering and clutch operation are supported by hydraulic auxiliary forces.
- The reservoir is located in the engine compartment.
- There are two marks on the dipstick located on the reservoir cap. One side bears the mark Cold for a cold engine (approximately 20°C) and the other Hot for a hot engine (approximately 80°C).

Pentosin Reservoir





- Check the fluid level (Pentosin CHF 11 S) with the engine stationary and cold (approximately 20°C).

Caution: Danger of damage to property if too much Pentosin CHF 11 S is filled or it it comes in contact with the coolant hoses when topping up or tilling in.

- Observe the following specifications in order to avoid overfilling and thus overflowing.
- Multiple steering operations (maneuvering) or/and actuating the clutch with the engine switched off change the fluid level in the reservoir. Fluid level rises. In this case, the engine must be run for approximately 20 seconds immediately prior to the fluid level check.
- If coolant hoses come into contact with Pentosin, thoroughly clean them with water IMMEDIATELY.
- Replace visibly swollen coolant hoses.

1. Start engine and run it at idle speed for approximately 20 seconds. Switch off engine.
2. Open the engine cover.
3. Open reservoir cap.
4. Wipe off the dipstick. Close and then reopen the cap. The fluid level should lie in the hatched area beneath the "Cold" mark (mark = maximum level at 20°C). Top up with Pentosin if necessary. *The upper "Hot" mark is intended for a fluid temperature of 80°C.

- Do not add too much Pentosin. The respective marks are for the maximum fluid level at the "COLD" or "HOT" temperature.

Note:
- If assembly work was performed previously, check the fluid level with the engine idling and without operating the steering.
- Multiple steering operations (maneuvering) or/and actuating the clutch with the engine switched off change the fluid level in the reservoir. Fluid level rises. In this case, the engine must be run for approximately 20 seconds immediately prior to the fluid level check.
- When topping up or filling in Pentosin, make sure that it does not come into contact with the coolant hoses.
- Observe the specifications in order to avoid overfilling and thus overflowing.
- If coolant hoses come into contact with Pentosin, thoroughly clean them with water IMMEDIATELY.
- Replace visibly swollen coolant hoses.





Bleeding the steering system

1. To fill the whole system after the installation of new steering components or lines or after a substantial loss of hydraulic fluid, briefly start the engine a few times and, when it fires, switch it off again immediately. This procedure causes the fluid level in the reservoir to fall rapidly, so constantly add Pentosin CHF 11 S. The reservoir must not be sucked dry.

2. If the fluid level in the reservoir does not fall any further when the engine is briefly turned over, start the engine and let it run at idling speed.

3. Rapidly turn the steering wheel from stop to stop several times so that the air can escape from the cylinders. At the end positions of the piston, do not pull the steering wheel with more force than is necessary in order to turn the steering (to prevent unnecessary build-up of pressure initially).

4. Observe fluid level during this procedure. If it continues to fall, add fluid until the level in the reservoir remains constant and no more air bubbles rise in the reservoir when the steering wheel is turned.

5. Switch off engine.

6. Wipe off the dipstick. Close and then reopen the cap. The fluid level should be in the designated "Cold range" (min./max. level at 20°C). Top up with Pentosin if necessary. Do not add too much Pentosin. In warmed-up condition, the fluid level must not exceed the "Hot max" mark.