roadmax

In the drain point at cooler connection, is the fluid coming from cooler side or from reservoir side?

gcalo

When you separate that connection you'll drain the cooler and the reservoir

So have a decent sized container at hand ready to collect that fluid.

Let it drain and drip for about 30 minutes

Also when done let the system run for a few minutes with the reservoir cap off so the system can expel any trapped air then finish topping off the reservoir fluid level.

roadmax

Thanks for details.
The reason why I'm asking is that if this is a return line (fluid returning to reservoir) ??
as per ZF instructions it can be done faster with engine running.

gcalo

Forget what ZF says.

Think dangerous moving objects as well as engine heat etc!

Just practical common sense

hatterasman

Did this over the weekend on an '08 E61. There is a loop of two hoses under the subframe with a hard line connection between the two. I disconnected the lines from their mounting bracket (10mm nut) and unscrewed the fitting and allowed it to drain. Then, I connected air to the rack side, covered the reservoir with my hand and applied

gcalo

Since you put air in to drain, I would let the engine run a bit with the F/E raised and reservoir cover off while moving steering wheel L to R a few times to ensure you let all the air out of the system.

roadmax

Here is how I plan to do it:
1.Drain the fluid from reservoir
2.Remove the hose from reservoir bottom (not from cooler connection)
3.Plug the reservoir bottom open hole
4.Put the open hose end in empty container to collect old fluid
5.Fill up the reservoir with fresh fluid
6.With engine running turn the steering wheel slowly from one side to the other, as old fluid drains into the container, fresh fluid level drops in the reservoir, add more fresh fluid, repeat steering wheel turns until fresh fluid comes out of the drain hose end
7.Shut down the engine
8.Mount back the hose end to the reservoir
9.Add fresh fluid to the required level
10.Flush completed

It is not clear how Dynamic Drive sway bar pumps operate, does fluid circulate back to the reservoir during normal cat operation?

hatterasman

I turned lock to lock several times by hand. (just pushing and pulling on the tire). This dropped the fluid level in the reservoir by half. I refilled the reservoir, started the car and turned the steering wheel lock to lock several times. No additional fluid was needed.

hatterasman

I looked at the lines under the reservoir. I decided not to dsturb factory clamps that weren't leaking. I looked at the quick disconnect line for the cooler. I didn't see any way to reach it. Then I found the compression fitting under the car. This was very easy to get too. 10 mm on the bracket, 21 mm open end on the nut and 17 mm on the fitting. Came right apart and the reservoir drained in my bucket. Absolutely no mess and no need to pour fluid into the reservoir with the motor running.

donston71@yahoo.com

wish I had seen your post before spending 2 plus hours trying to locate the power steering reservoir. I nearly took the entire engine apart, and still no power steering reservoir was found. Also have a liter of Pentosin that will never be used. Oh well, live and learn I guess.