[DIY] Power Steering

[99MPower]

Well, I just recently completed the power steering hose DIY.

I had found a couple DIY's and didnt find exactly what I was looking for, so I decided I would make my own. I dont have all the pictures I wish I did, but this is a VERY easy DIY. This is more for part numbers, and my issues with finding the "right" hose for the return line

First off, the return line hose that people make themselves, needs to be oil resistant and high PS.

I originally found 1/2" ID heater hose, and after talking to a couple people it was not oil resistant and did not have the PSI rating to be used for this application. The power steering fluid (ATF) is corrosive and can eat through the hose if you dont use the proper hose.



The hose on the left is the "right" hose to use. It's transmission cooler hose from NAPA with 400psi rating and oil resistant. The hose on the right is heater hose, and you can tell it doesnt have the reinforcements necessary for the PSI rating required.



This is the hose from Napa.

I also purchased a brand new intake manifold hose from the BMW dealer with my BMWCCA discount for $30. This hose is too cheap, NOT to get a brand new one with the PROPER fitting for the power steering pump.

:edit: in addition.. make sure you get the 2 new crush washers that go with the intake manifold hose. these go between the banjo fitting, and the bolt. These two washers "should" come with the new hose, but make sure you confirm. They are #3 in the diagram, but dont show up in the part number listing as they came with my hose :thumbsup:

Part #1 Intake Manifold part number 32411138419




There is a small fitting in the hose that runs from the hard line on the return line to the reservoir. After talking to a couple people, when you replace the hose with the NAPA hose, it will NOT cause any ill effects and no need to worry.

I removed the two old hoses and then removed the reservoir to clean out the filter contained at the bottom with 1-2 quarts of brand new ATF fluid. I ran the new fluid through the reservoir until the fluid coming out was looking brand new.

I then used brand new hose clamps, and installed the hoses on the reservoir to make it easier to clamp everything together. The transmission hose needs to be cut at 11.5" inches to reach from the reservoir to the return hard line.

Once the reservoir is installed back in the bracket, reattach the hoses to the return line and power steering pump.







Once all the hoses are connected, fill the reservoir with ATF. I used Mobil 1 synthetic ATF. Once filled to a decent level, start the car and rotate the steering rack FULLY from one side to the other a couple times to "bleed" the rack of any air. Once you have completed this, double check the fluid level in the reservoir, and then ENJOY


So you will need these parts.

3-4 quarts of ATF of your choice (1-2 for flushing reservoir, and 1-2 for refilling)
Napa part #H1945 ... 3ft of Transmission Oil Cooling Hose
BMW Part #32411138419
and then the new hose clamps

[fun2drive]

Nice Write Up.

[ImplicitFiber]

so you replaced all three hoses? What about the flow restrictor?

[99MPower]

just 2 hoses... flow restrictor was taken out and not replaced...

no ill effects...

[libravcs]

was the flow restrictor engineered for a reason?

[JETninja]

Huge thread on the subject a few years ago when a member put together a kit for a group buy....no one has ever shown conclusive evidence or data to support anything one way or another if you run the restrictor or not. I plan on doing mine sometime soon, will probably can it too....

[Nguyen]

^ Do you know if that kit is still available? I need to replace both hoses.

[JETninja]

^ Do you know if that kit is still available? I need to replace both hoses.

I have no idea, do some searching in the Group Buy forum.....

[LuxoM3]

FWIW - if the car runs fine without the flow restrictor, I suggest leaving it out... it appears under extreme spirited driving... aka redline... the PS fluid boils/foams and expands out the cap...

FWIW anyway...

[M13]

Great write up.

[Crazy 13immer]

Nice write up, I'll be doing this soon.

[SmellyGreek]

http://forums.bimmerforums.com/forum...d.php?t=124679

[ImplicitFiber]

I'm confused, you replaced hoses 5 and 1 with napa hoses? What about the upper left hose with no number?

[ImplicitFiber]

The steering rack with cooling coil pipe... do you replace it?

[JetBlackE46]

nice write up - thanks!

[Blanchimont]

I'm confused, you replaced hoses 5 and 1 with napa hoses? What about the upper left hose with no number?

This DIY is for #1 and #9, which most often leak in many cases.
-you replace these 2 with NAPA hoses
-in hose #1 you remove the banjo bolt and insert it in the NAPA hose and clamp it to the reservoir
-once you remove #9, from reservoir by remocing clamp and from hard line by crimping that section there will be a clamp in the mid-section of it which you remove and cut out that section and get the restrictor out of it
-then you put that restrictor in the NAPA hose and push it (with a stick or something) in the middle of the hose and put a clamp on it so it does not move.
-then you install #9 to hard line and clamp it down and clamp the other end down at the reservoir.

[Blanchimont]

http://www.m3forum.net/m3forum/showp...p;postcount=13

[AgentHubcap]

What's wrong with the OEM hoses? (assuming new ones)

[Blanchimont]

What's wrong with the OEM hoses? (assuming new ones)

Nothing wrong, but PS hoses can be replaced with NAPA for cheaper w/o hurting anything...at times the OE hoses leak at reservoir, at times they may leak from the crimpped part where the hard and soft line meet (#9).

When you use NAPA hose and use clamps and tight those bishes down, it is more secured and the chances of a leak are less

[RatedM3]

Just an update: At least In my area, all automotive stores only carry up to 3/8" transmission cooler hose only. So either call NAPA or go in person with this part number. I made the mistake of going without it and they told me they have nothing except 50ft rolls that can't be cut to size. I tried a few other places with no luck, even a tractor supply company. Looked online at NAPAs site and found that it said they had one in stock. Called in with the part number and the same fella that told me they don't have it told me the online inventory is wrong but they could order it. I could of had the part today if he had ordered it before noon. Learn from my mistake, luckily I didn't need it asap.

[cmzwirner]

Ill be doing this soon. My power steering hoses are bleeding fluid. All over my floor...

[oofaM3]

I did this fix a few weeks ago using the hose recommended by the OP. My local NAPA had the H1946 hose in stock and was selling it for $5/ft instead of $20 for the 3ft of H1945 and possibly having to special order it.

Heres the link... as you can see they are same.
http://www.napaonline.com/Catalog/Ca...946_0364349995

I think I bought 2 feet just to be safe but I think I would have been fine with 1 foot.

[cmzwirner]

Yep. My local napa has 1/2" ID goodyear transmission cooler hose. $4.50/foot.

Is the intake manifold hose prone to leaking, or would i be safe skipping it?

[ICTBMW]

I recently replaced everything in an effort to avoid laboring-effort trying to remove those clamps underneath the reservoir from the bottom of the car. Its a relatively inexpensive and an easy undertaking.

Replaced items:
PS Reservoir - $21 (bavauto.com)
PS Inlet Hose - $33 (bavauto.com)
Crush washer(s) - $2(bavauto.com)
NAPA H1945 Hose - $26 (left over length is good for another install)
Clamps - $5

The only issue I had was by accidentally moved the "reservoir clamp" out of stock position, this created a very difficult reinstall due to the stock short M6 bolt (I have to push rearward and rotate the bolt at the same time, there is no room behind the alternator terminals to work). I ended up buying an extra long M6 bolt from Homedepot to solve the issue.

[99MPower]

#9 hose is the only hose being replaced by the NAPA DIY hose...

#1 hose was bought new at your favorite BMW parts retailer (local dealer, RME, AutoHaus, thebmwpartstore, etc)