DIY: Power Steering Pump Replacement

Okay Ladies and Gentleman, a little background. I busted a U-turn last week -- when I cut the wheel back the other way I had no power steering. Fluid was nasty, but full.

I would like to thanks KOPerformance for a super speedy delivery at an AWESOME PRICE!!! I ordered it on Sunday at 11:30 P.M., got it today before noon. I paid $270 for a new LF-20 P/S pump (not reman) -- Bavauto wanted more than $500, and many other places wanted >$350 for a reman -- so if you need a P/S pump go to KOPerformance.

Okay, here is the long and skinny. The most painful and difficult part of this entire repair was getting drive belt off and back on. I have a clutch fan, so I can't just take it out and get to the belt. Directly to the left of the alternator pulley and to the right of the water pump is a tensioner pulley. My car has mechanical (spring force) tensioner pulleys, so if you have hydraulic ones, I don't know how they differ. It uses a 16 mm socket, the longer socket wrench you have the better. In addition, you will want to use a socket that doesn't require an extension (i.e. 1/2" to 1/4" drive) because with the fan right there you won't be able to get it in the close quarters. Just remember, for the mechanical tensioner, you don't have to take off the dust cap, there is a separate nut (so if you take off a dust cover and loosen that bolt, you are actually removing the tensioner pulley and not just relaxing the slack on the drive belt). Use Dexron III ATF or better. I used Mobil 1 Synthetic -- which was Dexron VI, so you probably can't even get Dexron III anymore.

This is the new pump


Yes, the fluid is black, NASTY!!!


Up close...


A Siphon I used to get the fluid out of the reservoir, this minimizes the amount that pours onto your head when you remove the fluid lines to the pump.


Look at the sun...still couldn't get through the muck that was my fluid.


Once again.


This is the fluid line to the power steering rack. Use a 17 mm open ended wrench to remove it -- fluid is going to come out, so make sure that you have a receptacle to catch it. If you look to the left of the picture, you will see the black plastic elbow -- this is the line from the reservoir to the pump. I replaced the hose clamp (I know you can't see the clamp)


By the way, the pump shaft shouldn't come out like this -- this means it's sheared.


The bolt attached to the bracket is (1 of 3) that holds the pump to the engine block. All three are 13 mm, and require a torque of 16 ft-lbs when reinstalling. I personally bumped it up to 18 ft-lbs for good measure because of the extensions needed to get to the bolts. The real difference between 16 and 18 ft-lbs? Negligible really...


** here is a lesson learned. Take the pulley off of the pump while it is still bolted to the car (3 bolt hold the pulley to the pump, 13 mm. Use a rubber mallet to tap it off). This will give you move room to move around to get the bolt (3 of 3) below. Similarly, when you are putting the pump back on, pump the pulley back on last. That way you can get a torque wrench up to bolt (3 of 3)

Bolt (2 of 3) To the right of the red. This is on the back side of the pump (bolt head facing rear of vehicle), top left.


Bolt (3 of 3) Center of the picture above the pulley. This is on the front side of the pump (bolt head facing front of vehicle), top left.


Old pump...once again shaft shouldn't come out.


Sheared shaft.


So this is how the pump works. This picture is of the volute of the pump. As you can see, it is NOT constant volume. Centrifugal force from the rotation causes the impellers (little slants of metal placed in grooves of the pump) to slide out and move fluid. When the volute gets smaller, the impeller slides back in the groove and everything is gravy. If you look close enough, you can see that one of the impeller pieces broke off and lodged in the thin region of the volute. This caused the pump to seize and the shaft to shear.


New pump in the car...she's a beauty.


Fluid hose connections made up. Note the new clamp on the reservoir hose. You may want to replace this hose, seeing that is you unhook it from the reservoir and pump, it pulls right out -- I did not replace it.


NEW FLUID!!!! Yes it supposed to be red, not black -- who would have guessed.


More fluid.


How you get under your car is your preference, I use ramps. Installation is EASY...just opposite of removal. I object to people calling this a 15-30 minute job. I would say 1-1.5 hours. It took me about 3 because I was taking pictures and fighting with the tensioner pulley (definitely get a friend to hold the wrench on the pulley nut -- I had to hold the tension from under the car and put the belt on at the same time, and it was not fun)

The last part after she is all buttoned up and refilled is to get the car off the stands or ramps and start it. Take the steering wheel from full lock to full lock at minimum of two times (from the Bentley manual). It was still difficult to turn at first and I was getting pissed. I gave the engine a little juice and tried again, and it worked like a charm. After that I refilled the fluid.

I did actually siphoned out the fluid in the reservoir after it started working again. This is because of all the crap that was in the lines that I couldn't get out (all the gunk in the rack and lines). I can tell that it mixed with other fluid, but it is still red. I plan to flush it (from the reservoir since it is a closed system) next week for good measure.

On a scale of 1-10 of difficult I would give this a 3. This most difficult part was getting the belt off and on. If you don't have a clutch fan, and can just pull out the fan and shroud -- this is even more easy. I did neglect to say take the cover off the bottom of the car, but I figured that was self explanatory. Hope this helps, because all the other write-ups provided little instruction. Feel free to PM me if you have any questions.

what you have described is exactly what happened to my pump and exactly how I changed mine. Great write up well done.

My pump cost £280 from Euro Car Parts

Great DIY!!! Thanks for posting. I looked at KOperformance website and there are two pumps available. LF-20 & LF-30. I own a 2000 323ci production date 8/99. With my luck I will have to buy the more expensive one. What is your production date? Is the pump stamped somewhere indicating the type of pump in the car. Is it easy to see from the bottom or the top?

To see what pump you need go to http://www.realoem.com/bmw/select.do

Enter the last 7 of your VIN, then do a search for the pump. And yes, the pump has a sticker on it that says what pump you have, but I don't recall seeing it when I was under the car.

I think the main difference is the pressure difference that the pump puts out (for the boost) but don't quote me on that. I have read a bunch of threads on here where people had a LF-30 and went back to a LF-20 because the steering was more like a sports car.

Either way, putting on a new pump made my steering a dream. I bought my car used, and it has never felt so good.

Good luck on the install.

I have no idea how you managed to do this without taking out the fan - there's just no room at all...

Can you explain your comments about the tensioner? My tensioner has a flat black plastic cap, with a T50 torx underneath the cap. Where is this other nut you are talking about?

I found some good pics in this post:

http://forum.e46fanatics.com/showthread.php?t=483472

In #8, he is loosening the torx I am talking about. Is that not the best way?

#2 in this picture is the tensioner pulley to the left of the alternator as you are looking at the engine.

There is a bolt on the tensioner pulley (not the one under the dust cover) that allows you to relax the tension. Keep in mind that this is for a mechanical tensioner, not hydraulic. It is just to the left of the alternator.

Here's a link to the page displaying the image:

http://www.realoem.com/bmw/showparts...05&hg=11&fg=18

So, to be clear, by loosening the bolt labeled "3" in the image, tension is removed? Do you have to manually move the tensioner, or is slack automatically created?

Awesome writeup!

Here is a picture of the belts, the drive belt tensioner pulley has the arrow going to it.

INCREDIBLE WRITEUP! so organized! i love it!

I'll be doing this soon. I have the LF 20 steering pump. Mine just gave out at 147k miles

Great DIY write up...thanks for posting...I will be doing this soon. I appreciate it.

Same pump and what happened to mine. That's an LF-20 btw. It should say on the sticker (which you can't easily see until you remove the pump from the car), and also the pump pressure 110, 120 or 130 psi.

LF-20's do have 2 types with different BMW part numbers. These are interchangeable. LF-30's are not directly interchangeable, you'd need different pipes.
See here:http://forum.e46fanatics.com/showthr...73#post5241673

More here:
http://forum.e46fanatics.com/showthread.php?t=345223

LF-30's are older, (generally cheaper and easier to find, they used them on older 5-series too) and easily distuinguishable as they're a different shape (looks like a "barrel" shape along one edge) and they don't have a plastic L-shaped pipe.

I wish we could obtain the service parts to rebuild these pumps which are so prone to failure ourselves.

Originally Posted by Shag

Can you explain your comments about the tensioner? My tensioner has a flat black plastic cap, with a T50 torx underneath the cap. Where is this other nut you are talking about?

Mine did too. From observation, my teccie did this:

From my post in another thread:
(Note route of belts if you may be unsure or are unfamiliar with them).
Prise black plastic centre covers from 2x belt tensioners (using a fairly thin screwdriver), use torx bit in strong socket wrench bar (turn centre torx silver socket you've revealed under the plastic covers you removed clockwise and entire tensioner wheel will pivot clockwise) to release tension adjuster enough to remove the belts (do for both belts).

Great thread. Thank you for the write-up.


Subscribed.

So, I never did get this done, and have been driving around with no power steering for almost 2 years now (good arm workout, lol). Figured it was finally time to try again, came back to the thread, and the pics are gone! Did anyone happen to save them off, anywhere? Or, ElDawson, do you still have them anywhere?

Originally Posted by Shag

So, I never did get this done, and have been driving around with no power steering for almost 2 years now (good arm workout, lol). Figured it was finally time to try again, came back to the thread, and the pics are gone! Did anyone happen to save them off, anywhere? Or, ElDawson, do you still have them anywhere?

Did this yesterday in my garage with a friend on his 02 330ci. Replaced pump, reservoir, and all the exposed hoses, and then flushed the system. Working slowly and methodically, it took about 7 hours. Here are the links we used (not all of them though, but you’ll figure out which ones are most useful).

As one of them says, don't skip the flush no matter what else you do, since you're already there. Even with all the new hoses, pump, and res, you can't believe the crap that came out during the flush.


http://www.dvatp.com/bmw/diy/power_steering_flush/
http://www.m3forum.net/m3forum/showthread.php?t=252164
http://forum.e46fanatics.com/showthread.php?t=649017
http://forum.e46fanatics.com/showthread.php?t=575499
http://forum.e46fanatics.com/showthr...+steering+hose
http://www.bimmerboard.com/forums/posts/477673

I can't see the photos from the original posting.
I can see photos in other threads....
Any ideas?

I have a 2003 325i with what I think is this same problem. Makes an awful noise when turning the wheel while parked.

No leaks, PS fluid level is fine. Fluid is Dark red, but not black or brown.

Having trouble finding a low cost pump. Advance Auto doesn't have any more of the low cost versions. The one they currently offer is $678!! The parts person on the phone even told me to sit down before telling me the price.

KOPerformance has a pump for just under $400.

My local BMW service guy (NOT a dealer) will replace it for $500.
I'd rather do it myself but It might be worth $100 to have someone else do it for me.

Rick

How many quarts of ATF do you need? I filled mine up with 1 bottle and the reservoir is emptied. Either I did not put enough in and there was air in the system, or I have a leak by the pump because there's nothing by the reservoir.

NVM. I have a leak near the pump itself. Noticed that if I turn the wheel in my driveway, fluid starts leaking out pretty quickly form underneath...