DIY e92 M3 Power steering upgrade/Blow-by fix

[08 E92 Jerez Black]

Good Morning Fellow car geeks, I wanted to give the group the pics of my fix of the only oil leak my car had when I got it 2 weeks ago, the dreaded power steering overflow cap. I joined M3post and started digging though old post looking at solutions members had posted. Some using a crazy screw on cap that cost $665 dollars ( I might have looked into an electric power steering if I was in for that much (like my friends race car uses) others just stuck a sock over it, which seams like a fire waiting to happen(oil soaked sock dropping on a red hot header) and the last one which seamed to work well but made checking the fluid a hassle was the brake overflow with a tube option. In the end I liked the swap to The 1M unit (also standard on all F-chassis models). But I was frustrated that no-one (that I could find) had a good solution to adapt the larger 3/4 outlet to the 1/2 hose the return on the e92 M3 used. I did what one user recommended and used a plumbing adapter but it looked horrible, And I had doubts that the rubber it was made of would last due to the caustic properties of the fluid used. I ended up at my local Sprint car shop digging through the selection of AN fittings in an attempted to use AN to adapt the hose size. but this proved to be ugly as well, going from 8 AN to 12 AN requires a large amount of product and you end up with a huge adapter that would not fit in the location, then purely by accident I placed 1 22 degree angled 8 AN to 3/8 NPT fitting and realized the threads almost treaded right inside of the 3/4 outlet, AWESOME!!! I went down and got a 3/8 NPT tap and taped the inside of the outlet pipe. it is surprisingly strong, I took my time and ended up with a treaded inlet that would actually handle tightening and pulling on it. The 22 angle also allowed me to clock the outlet. you need to face it more towards the front of the car otherwise the hose wants to contact the AC pulley below and that would be bad Hope this helps someone. Oh, almost forgot, this cost me less that $100. including all the AN and new fluid.

[08 E92 Jerez Black]

[08 E92 Jerez Black]

[08 E92 Jerez Black]

one more note, I cut a section off the original hose that was the same length as the AN parts and I used a crimp clamp. If you don't have crimp clamps get a kit from Amazon \

(http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1)
It's cheap and looks much better than the crap ones with the barrel screw that tights the unit. Those break easily and end up being the addition that cuts the crap out of you when your trying to work on your car.

[Shredicus]

Awesome and elegant solution! I was recently faced with this same quandry and took a slightly different approach.

I bought a regular barbed adapter stepped from 3/4 to 1/2 from autozone. Unfortunately It is a real pain in the ass to find 3/4 inch transmission hose since I knew regular heater hose would disintegrate pretty rapidly from the chf. I rubbed a little chf on a spare piece of heater hose to confirm these fears, and sure enough noticeable amounts of the hose deteriorated.

So I ended up buying a heavy duty goodyear power steering hose online but shipping was 3x the price of the item. The new hose is impervious to the chf and bridged the gap between adapter and reservoir perfectly when cut to size. I heated the exterior braid a bit and it shrank to fit the barbs with a plastic-like rigidity. All said and done it turned out pretty nice but I haven't installed it yet!

Hose

Reducer

PS: nice clamps! Makes the old wormgear look like junk

[08 E92 Jerez Black]

NICE, I looked for days for a clean step down from 3/4 to 1/2 and could not find anything that would withstand the corrosive nature of the power steering fluid in these cars (insert mental picture o f the acid based alien blood melting through the space ship if you are also a horror Geek! )

your solution would have saved my alot of time a week ago

[08 E92 Jerez Black]

On the old worm gear, my first attempt used 4 worm gear type clamps and was the ugliest thing I've ever done to a car. I felt guilty for days so I re-did it when I ripped the car apart to replace the bearings.

[tom @ eas]

We went this route on a few of our track cars, definitely much better than the previous piece. Even the same mounting bracket can be used.

[08 E92 Jerez Black]

Agreed Tom, the solution is the best one overall after figuring cost and simplicity in my opinion.

[Atomicteal_M3]

Originally Posted by 08 E92 Jerez Black

one more note, I cut a section off the original hose that was the same length as the AN parts and I used a crimp clamp. If you don't have crimp clamps get a kit from Amazon \

(http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1)
It's cheap and looks much better than the crap ones with the barrel screw that tights the unit. Those break easily and end up being the addition that cuts the crap out of you when your trying to work on your car.

Where did you buy these 2 pieces?

[08 E92 Jerez Black]

LAWSON'S Performance in Petaluma CA. but here are part numbers for the same stuff

45 degree An to 3/8 NPT
Aeroquip Part FBM5023 $8.97 from summit

Aeroquip Socketless Hose Ends
Part FBL1512 $6.97 from Summit

http://www.amazon.com/Vermont-Americ...=3%2F8+npt+tap

or any other vendor, I tend to try and make sure all my AN stuff is from the same company

[Atomicteal_M3]

Originally Posted by 08 E92 Jerez Black

LAWSON'S Performance in Petaluma CA. but here are part numbers for the same stuff

45 degree An to 3/8 NPT
Aeroquip Part FBM5023 $8.97 from summit

Aeroquip Socketless Hose Ends
Part FBL1512 $6.97 from Summit

http://www.amazon.com/Vermont-Americ...=3%2F8+npt+tap

or any other vendor, I tend to try and make sure all my AN stuff is from the same company

You rock brotha! Will be doing this mod very soon! This needs to be a sticky!!

[08 E92 Jerez Black]

I'm a bit new to this, how would I do that (publish this) I would love to help others with this fix, seams like it would cover a lot of cars right?

[08 E92 Jerez Black]

One Last Addition, the BMW part number for the reservoir is 32-41-6-767-161 and is roughly $32

[tom @ eas]

Originally Posted by 08 E92 Jerez Black

I'm a bit new to this, how would I do that (publish this) I would love to help others with this fix, seams like it would cover a lot of cars right?

All current production models (that do not have E-Steering) use the revised part number.

[M3Bimmer77]

Sorry OP but don't understand the problem you had. I guess it's not an oil leak, as initially stated. It's a steering fluid leak, right? But still don't understand what was the problem. Overflow?

[Z K]

Originally Posted by M3Bimmer77

Sorry OP but don't understand the problem you had. I guess it's not an oil leak, as initially stated. It's a steering fluid leak, right? But still don't understand what was the problem. Overflow?

The power steering fluid overflows when you take it to the track. Very common problem on the M3.

[08 E92 Jerez Black]

my car (and many of the BMw's using that cap and tank) had blowby that escaped the system all over in the area it was mounted. I always thought the breather on the cap should only allow for a pressure balance under hard workload, but since this cap allowed actual fluid to escape the system and get all over the passenger side of the engine compartment I considered that a leak, since no engineer in the right mind would intentionally want oil out of the system without giving it a path away form anything hot. The fix I used complete stops anything outside of air to come out of the tank, since the new tank captures any blowby and lets it go back into the system.

[M3Bimmer77]

Gotcha. I don't track mine so maybe that's why I couldn't understand your problem. Unbelievable a company like BMW still making cars with this little problems!!!! Anyhow nice project I guess. One thing that concerns me of your fix is that the reservoir pipes are meant to work as males and you iare using them as females threading the inside. I hope that wall is strong enough and won't start cracking with the pressure, heat and time.

[08 E92 Jerez Black]

Believe it or not, I don't track mine either, just street driving, but I do drive it hard when the
Mood suites me, and I was able to get
It to leak. As far as the strength of the wall, I had the same concern at first, but after running the tap all the way till it was bottomed out I will tell you it is much stronger than even I would have imagined. Remember this is all
Low pressure as well. If you do this mode, take your tad and keep cleaning the treads after each run. You'll
Be happy you did it!

[Z K]

Originally Posted by 08 E92 Jerez Black

Believe it or not, I don't track mine either, just street driving, but I do drive it hard when the
Mood suites me, and I was able to get
It to leak. As far as the strength of the wall, I had the same concern at first, but after running the tap all the way till it was bottomed out I will tell you it is much stronger than even I would have imagined. Remember this is all
Low pressure as well. If you do this mode, take your tad and keep cleaning the treads after each run. You'll
Be happy you did it!

It overflows when you use the power steering a lot. Fast back and forth steering on mountain roads or anywhere else you are working the power steering hard. The M3 is a heavy car so the power steering gets hot - that fluid expansion is what causes the overflow.

Has anyone tried higher temp power steering fluid?

[08 E92 Jerez Black]

I've been happy with the CHF-11s, it's the same fluid my Cayenne Turbo uses and that thing is a tank, no issues whatsoever with actual breakdown of the fluid or burnt fluid in either car.