A/C Compressor shaft seal for Bosch Behr

[clarkson]

So I have a leak out the front of my air con compressor, it is the Bosch Behr compressor vane pump style.

I stripped down a spare seized compressor I had of the same style, and came across not just o-rings in the front but the carbon seal which is spring loaded.

In my research this carbon seal is no longer available.

Is this the case or has anyone here successfully rebuilt one of these.

As I have three compressors I was thinking of maybe finding the least worn shaft seal out of the three, linishing the contact surface, maybe pre-loading the spring a little for more pressure and seeing how that goes.

[flyboyx]

personally, i have never had one apart, but it doesn't sound like you have anything to lose. i guess the worst thing that can come of this is a little r134 into the atmosphere or you having to buy a new/rebuilt one.

[ELVA164]

The Bosch compressor is 100% not compatible with r134, by the way. If you're having an issue, you can pick up a brand new Sanden r134 compressor for $200.

Edit: I'm not sure what the shipping to AUS would be, though.

[clarkson]

The Bosch compressor is 100% not compatible with r134, by the way. If you're having an issue, you can pick up a brand new Sanden r134 compressor for $200.

Edit: I'm not sure what the shipping to AUS would be, though.

Thanks for the replies. Do you need to make up bracket for the Sanden compressor?

In what way is the Bosch compressor not compatible with R134a? Is it the seals or the pressures?

I did have my old M20 stroker running a Bosch Behr with R134a reasonably well...

[ELVA164]

I had to do a ton of research when getting my car ready to convert, and apparently the Bosch has issues with both seals and operating at the higher pressures r134 requires. I guess its design means it's not very effective.

And yeah, the Sanden compressors do use a different bracket. I forgot that part because my car came with an old Sanden and a bracket. You can buy the correct bracket, however.

[clarkson]

So I am going to try another spare used compressor today. Hope the shaft seal is in better nic than the one in the car, I only pulled 10grams of gas out of it in prep of swapping compressors.

Here is the link I used to strip the bosch behr compressor down, this actual photo is of the pita carbon shaft seal:

http://s115.photobucket.com/user/bearing01/media/Bosch%20Behr%20Retrofit/237-3737_IMG.jpg.html

[clarkson]

OK so I found the seal kits on ackits.com.

Part numbers are MT2107 for the seals and MT2052 for the carbon shaft seal.

Problem for me is they don't ship internationally :(

[jeffnhiscars]

Im going to weigh in on this. There is a BMW service bulletin that tells you which Bosch compressors are r134a compatible. This is totally seal dependant as none of them...I repeat NONE are designed to work at the higher pressures that r134 prefers. Having said that, I have had converted cars running on the original compressors and they worked extremely well. Im going to say its the luck of the draw.

I did one Sanden conversion and one Seiko and both require a mounting kit. The company that made them was bought by APG (Air Products Group) and they are no longer in production. I got my kit for an M20 off of Amazon which is the only source I know of and that was for the Seiko (who now owns Valeo too).

Bottom line is, an r134 specific compressor will give you better results and runs about US$200. Whatever compressor option you choose,make sure you have the mount kit in your hands before buying the compressor to avoid major sadness.

Just my AU$.02 :)

[clarkson]

Just my AU$.02 :)

Love it!

I have recently been down the genuine BMW compressor path for a mates Sport Evo. BMW sold us the compressor (which was a reman Bosch Behr style from a company in Switzerland) but they could not supply us with the retrofit kit (bracket) after we ordered it and waited 2 weeks for them to tell us it was nil stock.

And after a brief research on the web for aftermarket brackets to fit M10 and S14 blocks I gave up. If I can just get this seal kit fro ackits then I am happy to rebuild mine, I will make one good one out of the three I have, one is off the sport evo ;D

would ackits deliver to Canada? My wifes family lives in Vancouver.

[clarkson]

So ackits.com will not ship internationally, nor will they take a foreign credit card. They won't even take a USA credit card (I asked a mate to try) if the billing and shipping addresses are different! They are forgoing a lucrative overseas market.

So as per a pm on here from a very helpful r3vlimiter, I tried polar bear in florida.

Yes they have the two kits I need and they ship internationally. I contacted them to see if the parts were r134a compatible and they replied quickly in the affirmative.

So the parts are on their way, and I will rebuild the compressor when they get here.

What makes me pursue this path is the lack of availability of a modified bracket to suit another compressor like a Sanden. And one other Sport Evo owner I know fitted nd aftermarket compressor and bracket and the bracket cracked.

Also the genuine new BMW compressor I fitted to the other sport evo was a reconditioned wing cell compressor just like the Bosh Behr compressors, just with different mounting brackets.

[clarkson]

Part numbers for the Bosch Behr stuff from Polar Bear in Florida are:

SS0837

and

GA4390KT

[clarkson]

So I rebuilt the compressor last night after work with parts from Polar Bear.



In the picture at the back of the bench is the face the carbon seal works on. I decided to linish this smooth with 1200 wet and dry as it had some fine grooves in it.

I also decided to keep the carbon seal dry on installation as to let the seal bed into the face.

I have found very little information on this accept a member here who has been great.

Next is to bolt it up, vac it down and if no leaks then gas it up and see....

[clarkson]

Success! I just stuck my head under the car and there is no dye at the front of the compressor.

Finished the rebuild a few weeks ago and have been running the car with a/c since.

I have blown my thermo fan fuse and it keeps blowing even with a new fan so I have to diagnose that and only use the a/c at highway speeds but the a/c is cold, compressor is quiet and working well.