Noisey Power Steering pump problem solved

[beamerNZ]

Hi All,

I would like to share how I solved my problem to help others that may have a similar problem.

It all started when I accidentally put brake fluid into the power steering reservoir. My BWM 318i 1994 model went fine for a day and then when I started her the next day the PS fluid started frothing and spewed out of the reservoir cap. At the same time the PS pump started making a grinding noise when I turned the steering wheel.

I immediately got some propper PS fluid and started to flush the system by sucking out the old fluid in the reservoir with a syringe and topping the fluid up with fresh fluid. I then started the engine and turned the steering wheel full lock to both sides a few times. I repeated this a number of times to get the air and the old fluid out.

After all the old fluid was out I noticed that the new fluid was still frothing and assumed that air must be getting into the system somewhere. I checked all the connections but could not find any leaks until I spotted a leak comming from the power steering pump shaft.

I took out the pump - which is easier than you might think - and opened up the pump on a very clean surface. Cleanliness when you work on this pump is extremely important as it is a rotary vane pump which operates on very fine tolerances and high pressures. I took the 4 bolts out that held the pump together, took out the circlip that holds the rotor to the shaft and replaced the oilseal in the pump. The seal cost me $2.00.

Here is how to do it:

Removing the Pump

1. Take out the air filter by undoing the 2 bolts that hold it in place and by unscrewing the clamp that holds the outlet rubber duct to the air filter. Disconnect the plug that is attached to the filter by twisting the plug. Then lift out the air filter. The air filter is the square box on the right hand side behind the light when facing the car from the front (my car is right hand drive).
2. Suck out as much as possible of the PS fluid with a syringe and do not reuse. Place plenty of rags under the car as there is still a little bit of fluid in the hoses.
3. Remove the cover of the lower idler tensioning pulley with a screw driver (marked 1 in my sketch). Fit a socket and rachet to the bolt holding the pulley and lever either up or down. It is harder to describe it than it is to do it. Just try and lever the pulley and you will feel the whole pulley give as the hydraulic spring tensioner gives way. This gives you enough slack to slip the serpentine belt off the idler pulley and off the PS pump pulley (marked 2 in the sketch).
4. Undo the 3 bolts on the PS steering pulley. It is easier if you use 2 spanners, one on each of 2 bolts to hold the pulley from turning. To get the last bolt out place a screw driver through on of the holes to hold the pulley from turning when undoing the bolt.
5. Undo the high pressure hose from the PS pump from the top of the car and the low pressure hose from the bottom of the car. I used an extension on my rachet to undo the low pressure hose from the bottom.
6. Undo the 2 mounting bolts holding the PS pump from the top of the car to free the pump and remove from engine.

Replacing the Oil Seal

1. Clean the exterior surfaces of the pump thoroughly. I used petrol to do this.
2. Split the pump by undoing the 4 bolts - you may have to give the pump a tap with a mallet to seperate the 2 halves.
3. Remove the internals and while pushing the pulley side of the shaft remove the circlip that holds the pump rotor in place.
4. After removing the rotor and shaft, prise out the old oil seal and carefully fit the new seal taking care to slide it squarely into the hole - a tap with a mallet may be required to get the seal to sit flush with the external surface.
5. When assembling the pump take care to fit the vanes into the rotor with theit flat sides facing outwards. This ensures that the vanes make good contact with the housing. If this is not done the pump will not deliver the correct pressure resulting in reduced power assist during steering at low speeds and standstill.

To finish the job reverse the procedure above.

Attachment shows a picture of what the pump looks like and the sketch of the serentine belt.
Get a basic understanding how the pump and power steering works at this site

http://auto.howstuffworks.com/steering4.htm

[ROGGERPAC]

Hi all,

I have a 1995 BMW 318is and am having great difficulty in finding the proper seal to replace in the PS pump which is leaking.

It has a Luk PS pump model LF65A, Luk model #2106126 so the rebuild kits that are out there are not for this pump.

The shaft oil seal which is leaking is a CFW 02-105203 (19.05 X 30 X 7).

Any body have any suggestions as to where to look for this seal...I have searched online all day with no luck

[beamerNZ]

Not sure which country you are from. Have a look at http://www.sealsfast.com/pages/DR/dr102.html