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Hello,
Where I can find the complete procedure to change the power steering oil with EDC system?

The EDC rear damper share the power steering oil with steering power oil tank, now I want to change the oil, how to do?

Also, what type power steering oil I need for it? Just normal ATF oil for normal car or need special power steering oil? Thanks.
 

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Hello,
Where I can find the complete procedure to change the power steering oil with EDC system?

The EDC rear damper share the power steering oil with steering power oil tank, now I want to change the oil, how to do?

Also, what type power steering oil I need for it? Just normal ATF oil for normal car or need special power steering oil? Thanks.
Hi!
You just have to loosen the low-pressure side of the feed lines to the power steering reservoir fill in new fluid while letting the old out to flush the system
(engine running) When the outcoming fluid is clear/without recidues, stopp and top up the system.
I have never done this personally but I believe this is the correct procedure. Be careful not to spray the oil all over the engine bay.

NONONO!!!!! No ATF, PLEASE!!!!!!! Read the owners manual, the correct fluids are specified there. I addition the correct fluid type is printed on the reservoir cap.
As your car has the EDC (a 3.8 then) the fluid should be pentosin CHF 11S

:cheers:
Sakke
 

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Replacing pentosin procedure....how exactly?

Hi!
You just have to loosen the low-pressure side of the feed lines to the power steering reservoir fill in new fluid while letting the old out to flush the system
(engine running) When the outcoming fluid is clear/without recidues, stopp and top up the system.
I have never done this personally but I believe this is the correct procedure. Be careful not to spray the oil all over the engine bay.

NONONO!!!!! No ATF, PLEASE!!!!!!! Read the owners manual, the correct fluids are specified there. I addition the correct fluid type is printed on the reservoir cap.
As your car has the EDC (a 3.8 then) the fluid should be pentosin CHF 11S

:cheers:
Sakke
Found this post from Sakke. Still looking for the procedure though.
Question is: Which hose do I have to disconnect exactly? Is that the return pipe to the reservoir?
 

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Found this post from Sakke. Still looking for the procedure though.
Question is: Which hose do I have to disconnect exactly? Is that the return pipe to the reservoir?
Yes, the return pipe is the low pressure one.

I had to do this a while ago when I had to replace the cooling pipe that goes right in front of the car behind the grille.
 

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Flushing the system........

So I dsconnect the return pipe from the reservoir? And the reservoir does not empty itself at that moment?
The returnpipe in a bucket I reckon, start the engine en fill up the reservoir untill clear green stuff is coming out the return....something like this?

W
 

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I disconnected the other end of the pipe (at the pump) and let that drain into a bucket (placed under the PAS pump) until the reservoir was below the return pipe level.

I then reconnected the pump end of the pipe and detached the reservoir end and let that dangle in the bucket.

Put the engine on tickover and slowly kept topping up the reservoir until nice new liquid appeared out of the return pipe below.

I also took the opportunity of fitting a new filter and gasket while the reservoir level was low.
 

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Do you know if this procedure "renews" the oil in the rear shocks

Hi Mmm-Five.

According to the Bentley Manual, they recommmend turning the steering wheel from lock to lock 2 times. I suspect this forces all the old oil out the power steering box.

I also suspect the procedure above does not change the oil in the EDC shocks, as there are controlled by self levelling valve (SLV) connected to the rear sway bar. Once the car is in equilibrium, I suspect the SLV isolates the pressurised system from the shock absorbers whilever the car isn't trying to level the car.

When I removed the rear shocks from my car, there is an initial unload of CHF 11S, which I suspect comes from the pressurised accumulators. Then when the shock absorber is disconnected from the oil pressure line, another volume of CHF 11S is unloaded. Once the shock absorbers are removed from the struts, it takes a considerable number of strokes of the shock absorber before oil stops unloading from the shock. I'd estimate there is about one litre of fluid in the rear suspension, i.e. in both accumulators and both shocks.

To check the fluid level in the reservoir, the Bentley manual recommends raising the rear of the car until the rear wheels are off the ground. The oil level should be no more 25mm above the base of the oil screen in the reservoir. I suspect this operation also results in maximum exchange of pressurised oil between the shock absorbers and the power steering pump. With the car off the ground, the self levelling system, thinks the car is too high, so the valve lets fluid return to the pwer steering reservoir from the rear shock absorber.

Reg.
 

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I only used the easier method as I've removed my accumulators & SLS system and have the system looping back before it gets to the SLS valve, so only needed to flush the recirculating system rather than the dampers too.
 
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