1st Gen R53 Cooper S Mini Cooper S (R53): Power Steering Pump/Fan/Duct Installation

OMFG!!!!

The MOUNTAINS of brush dust (looks like some copper/carbon matrix) are MASSIVE!!!!! When tapping out the shaft from one of the bearings, tons and tons of really fine dust fell out!

The brushes are about only half gone, so I'm gonna clean it up and put it back together and see how it all works out. I'll take some photos and post up what I've learned in a bit.....

Matt

 

Text now...

photos to follow:

Remove the pump/motor assy from the frame. This is 4 10mm nuts.

remove the small frame part from the pump/motor assy. This is 2x T40 Torx bolts.

Remove the pump from the motor assy. This is 3x T27 Torx bolts. You may have to loosen the hose clamp that holds the pump cover on the pump. You don't need to remove it, but on mine the clamp had to be moved a bit to gain access to one of the T27 bolts.

Remove the stator cover from the stator. This is 3x T20 Torx screws.

When you pull the cover off, it will fight you because of the magnets. Don't worry it will come off. There is an o-ring that seals the assy...

you will start making an even bigger mess here as the dust starts to come out.

There is a single snap ring that holds a sealed bearing at close to the right position on the stator shaft. Remove it.

I used a hammer to tap the stator shaft out of the bearing, as I didn't have the correct press stuff to do it really correctly. I don't actually think you need to remove it though.

Most of the dust cakes up inside the stator windings. You can poke at them and tap stuff, use safety glasses and a mask if you use compressed air. The dust is very, very fine. And there is lots and lots of it.

I used water with some soap in an ultrasonic cleaner to clean stuff. I kept the sealed bearing out of the water so it wouldn't get screwed up. What a mess!

With all the parts clean, I put them back together.

If you do take the stator off the electronics pack, the brushes can be pushed into the brush guides and they will stay there. If they don't pop out during assy, it's easy to spring them free.

The o-ring for the case had stretched, so I had to poke it here and there to get it together.

Also the motor shaft has flats that go into the pump. Don't force the pump onto the shaft without making sure that this is all ligned up! That'll screw it up for sure.

Once it's all back together, just follow the excellent instructions already referenced in the thread.

Matt

 

The duct to the power steering fan was added in the '06 model year. I have a very early '05 vert MCC that doesn't have it, an August '05 build MCS that doesn't have it, and a Sept '06 build MCSa that does have it.

Good writeup BTW!

 

Almost fell out of my chair laughing. Thanks, now I'm extra motivated to pull the pump on my car.

I have a 06/06 MCS (12mm bolts) that doesn't have the duct.

 

With some photos...

Remove the pump/motor assy from the frame. This is 4 10mm nuts.

remove the small frame part from the pump/motor assy. This is 2x T40 Torx bolts.

Remove the pump from the motor assy. This is 3x T27 Torx bolts. You may have to loosen the hose clamp that holds the pump cover on the pump. You don't need to remove it, but on mine the clamp had to be moved a bit to gain access to one of the T27 bolts.



Remove the stator cover from the stator. This is 3x T20 Torx screws.

When you pull the cover off, it will fight you because of the magnets. Don't worry it will come off. There is an o-ring that seals the assy... This photo is post-cleaning....


you will start making an even bigger mess here as the dust starts to come out.

There is a single snap ring that holds a sealed bearing at close to the right position on the stator shaft. Remove it.



I used a hammer to tap the stator shaft out of the bearing, as I didn't have the correct press stuff to do it really correctly. I don't actually think you need to remove it though.

Most of the dust cakes up inside the stator windings. You can poke at them and tap stuff, use safety glasses and a mask if you use compressed air. The dust is very, very fine. And there is lots and lots of it.



I used water with some soap in an ultrasonic cleaner to clean stuff. I kept the sealed bearing out of the water so it wouldn't get screwed up. What a mess!

With all the parts clean, I put them back together.

If you do take the stator off the electronics pack, the brushes can be pushed into the brush guides and they will stay there. If they don't pop out during assy, it's easy to spring them free.



The o-ring for the case had stretched, so I had to poke it here and there to get it together.

Also the motor shaft has flats that go into the pump. Don't force the pump onto the shaft without making sure that this is all ligned up! That'll screw it up for sure.

Once it's all back together, just follow the excellent instructions already referenced in the thread.



Matt

 

Dr O, I see you are a fan of the "Lion King"

WOW, I like the way the parts clean up with water and a little soap. Care to share info on the make of the ultrasonic cleaner?

 

I've got two kids...

5.5 and 3, both girls. And a wife that likes craap from Disney... We have more stupid DVDs than I ever knew existed!

My ultrasonic is a Branson. But you can get MUCH cheaper ones from Harbor Frieght or eBay...

I'm at my 5 year olds chess class now, and will add some more photos later...

Matt

 

Glad someone finely did a writeup on this....I remember someone did a oral writeup on another site, but did not have pics, so +1!!
I have the duct, installed it about 3 years ago from moss..
It is so easy to remove when you do oil changes, just pop the 2 screws off where it connects to the vent side, leaving the fan connected, then bend it out if the way.
If you have the older fan holder without the holes for the vent (my 05 s, late 04 production did not), you will need to modify the fan holder by adding 2 holes, easy...
Cheap, easy mod...if it saves one fan, or makes the fan last 50% longer, then it has paid for itself!!

 

Thanks Matt.

 

i leak

 

Does anyone know if brake cleaner -- the stuff in the pressurized can -- will do any harm to the stator windings?

 

I don't think it should

but I wouldn't soak them in it for long! Also, another thing to keep in mind is that there are lots of small gaps in the winding. It looks like once it's wound, they use some sort of conformal coating on the wires. Long and the short of it is whatever you use should be something that can dry and evaporate. After cleaning mine I set it in the sun for 20 min or so....

Matt

 

Couple of other comments...

first off, don't use any of the cleaners until you've physically removed the clumps that are packed in there.

Second, changing the brushes is possible, but it requires a small spot welder to to attach new brushes. I'd say skip this for all but those with the access to the correct tools.

Third, this is only the electrical motor side. I didn't take the pump apart to look at it's seals or the like. So if someone wants to take that half apart and see what there is to see, have at it!

Matt

 

Just a quick follow up...

got some Red-Line synthetic power steering fluid, and finished up the job. And it all works! So anyway, for those of you considering this, I'd suggest that before the system fails (in case something inside does get damaged), to drop the power steering pump/motor, remove the motor case, and clean out all the debris.

Another item to consider, is that dropping the full subframe is some more work, but then you can clean out more of the old fluid, and not have quite the mess that is left by doing the work from under the car. But then again, I don't have slender hands (really a PITA on cars with as tight a package as the MINI), so it's hard for me to reach up to all the little tight spots that you need to get to.

My car has 112k miles on it, and I live in hills so the system gets quite the work out. I'm hoping that this repair outlasts the rest of the car.

Matt

 

As far as the pump heating up - if the fluid gets hot - it would add to the thermal load of the pump possibly. In that vein would some sort of small fluid cooler for the PS fluid be helpful?

 

Some have talked about it...

but I don't know any that have done it.

Matt

 

Just add on an auxiliary power steering cooling fan! Now with on-demand sprayer! This should double the cooling power of the OEM fan.

 

My car is going under the knife for a new PS pump next week. Started going out intermittently a week ago, but so far only when I start the car. If I shut down and restart it comes back. This is after almost 7 years and 130k hard miles, including a few track days every year. That actually seems like a decent service life to me.

Estimate was ~$600 all up with brand new pump, which didn't seem too bad. I guess the pump prices have come way down in recent months.

Anyway, hope this information adds some value to the thread.