M3 Power Steering system question. [Archive] - Bimmerfest - BMW Forums

M3 Power Steering system question.

06-24-2005, 08:12 PM
Greetings All,

Do any of you know any details on the 2001/2 M3 power steering system ?

I'm particularly interested in the cooling part of it, if any.

Some background to my situation,
I just finished about 10 hot laps and a cool down lap at Wakefield Raceway(Sydney,Australia), when I was driving down pit lane. All of a sudden my steering went heavy and there was a lot of smoke coming from my front brakes. Took the car for an extend cruise on straight country road near track thinking brakes had not cooled enough on last lap. Stop in raceway car park and everything seemed fine. Opened the hood anyway to check things out as there was a very strange smell coming from the engine bay.
Turns out that I had boiled my power steering fluid, which in turned completely melted the plastic level indicator attached to the power steering reservoirs cap. This has then travelled though the system to the power steering pump and completely stuffed it. :mad: Hence cannot drive car and had to be towed 200km back to Sydney. :cry:

Also the average temp for the day was about 10 degrees celcius and wet. :dunno:

Anyway, because it is now the weekend I have to wait to get the car to my mechanic to find out just how bad things may be.

Any thoughts or comments welcome.

06-25-2005, 04:37 AM
Something wrong there. I and others have run teh cars hard in much higher heat and never overheated the PS fluid.

There is a cooling loop in the system.

06-25-2005, 06:24 PM
Thanks for the reply Pinecone :)

After having a bit more of a think about it, I pretty sure there must have been something wrong to begin with.

Especially when I know down the main straight at Wakefield I can top out @ 185km/h in my old standard 98' WRX and the M3 was struggling to get to 170km/h.

I'm really hoping now that there isn't anything wrong with the engine.

06-26-2005, 08:21 AM
Not sure of the straight length, but at Watkins Glen I look at 145 MPH on the back straight, VIR qabout 135 MPH on the straights. Even BeaveRun, which is pretty short I saw 120 -125 MPH (200 - 210 KPH).

06-27-2005, 06:42 AM
Thanks again Pinecone. :thumbup:

The following link has info on Wakefield if your interested,


Have notice some links on the e46 2001-2005 service manual, so will try to get a hold of a copy to help find out what possibly could of failed to cause this problem.

06-28-2005, 03:01 PM
Looks nice. What's the exchange rate? Book the whole track for you and friends for $1850AU? Cool.

But looking at the pic (I couldn't find a track diagram with any scale) I would say that you car should be a good bit quicker on the the front straight.

06-29-2005, 01:47 AM
That's exactly what we do, 3-4 times a year, 20 or so of us get together to book the track for a day. It's a great safe way to enjoy your car. :)

That's also where the power steering stuffed up on me.

Well, the juries out, will have to replace most of the power steering system. :cry:

Early diagnosis is that a plastic value in the steering rack failed :dunno: ,this stopped fluid circulating through the system, pump heated up and boiled fuild, boiling fluid melted pretty much all plastic components.

Will have to confirm this as it was explained to me pretty quickly, will post some pictures soon.

Side question, Can you buy the CSL steering rack parts for an M3 if you don't own a CSL ?

07-04-2005, 05:35 AM
Got the car back, good as new, but unfortunately BMW would not sell CSL parts unless I could prove I had a CSL (figure that would happen).

Anyway, to give you an idea of how hot the power steering fluid got, check out the attached picture of the power steering fluid reservior cap. For those of you that don't know what it normally looks like, the attached picture shows about 5% of what should be there. :yikes:

Ended up replacing everything to be sure that this won't happen again.