Ac Compresser Clutch Issue..

[Boggie1688]

Sup guys...wellz finally I'm taking my first step to get this car fixed...its summer now...so i can start fixing stuff. My first step is to fix the AC on the car...its hot here in cali...soo i wanna get that fixed first.

I had the ac checked out and the compressor isn't leakin ... the mechanic actually said that...the AC clutch that connects to the fan belt that runs the AC has gone bad. He says he can't fix the clutch because he doesn't wanna deal with warrenty issues if his work doesn't hold up...or if it fails. So I've decided to do this myself...I'm not a genius under the hood but my dad will tell me what to do...and I'll do the wrenching myself..

Now my question...since I have a bad AC clutch...is there any place where I can buy the components needed to fix the clutch? Instead of replacing the whole ac system itself? I'm not a guru at finding car parts online...and was hoping you guys could help...THANKS!

Boggie1688

[Rocky A.]

Ended up replacing the whole compressor, and converting to R-134 in the process. I had the dealer order a replacement clutch assembly that "allegedly" fit my compressor, but when I got it, it was clear that this replacement wouldn't go on my old compressor. Plus, my compressor's shaft had become sort of egg-shaped over time, so it needed to go anyway. Your best bet for parts are either a reputable local A/C shop or your BMW dealer. Join BMWCCA if you haven't already, gets you a 10% discount on parts at most BMW dealers.

Good luck.

[gale]

check a few places. I was able to get mine working properly again by just re-machining the clutch surface & shim/set the gap a few weeks ago & didn't have to mess with the solenoid business. Indiviual a/c compressor parts aren't cheap. Here are a few sources that sell just the clutch, besides the dealer:

http://www.impexfap.com

http://www.hancockindustries.com

And of course, you can always try BMA, Maximillian's, etc. It might not be that much more expensive just to get a complete rebuilt compressor.

[winfred]

what flavor of car??? brand of compressor? some clutches can cost as much as a whole compressor which can take a dump and take your new clutch with it, if it's a nippondenso (mostly aluiminum) the rubber lined face plate fits lots of asian cars and some american stuff too, most of the time the pulley is different but most of the time the bearing is the same and can be pressed out and installed in your pulley, the same for the coil. the bosch/seiko compressors can be a pain to track down and expensive

[Boggie1688]

Yea I went down today to the local car store...and hes like wellz...for the clutch itself its $370 and if you got an actual band new compressor...its like $420...soo its not a big difference and you might as well get a whole new compressor..so I was like god damn screw it...i don't have 420 bucks to throw down on AC...I can get a HID installed for 420 bucks...

Gale...remachining your parts...fill me in on that...I'd like to know what you did...maybe I can some how figure out what that all means and try doing it...might as well try....oh and last question...i was thinking...Since I'm poor and probably can't get this AC to work...I was thinking maybe I should just take all the AC components in the car out...making it slightly lighter...and slightly faster! But the ac clutch runs on the fan belt...and I was wondering what would happen to the belt if I took the compressor of it...

[MBXB]

I got a quote from Hancock Industries for my 540i:

New Compressor with New Clutch: $$295 plus $100 core charge
Reman Compressor With clutch $233.55 w $100 core charge
Clutch ONly $108 plus $50 core charge

How easy is it to change the clutch?
Lemme guess.. Special Tool XX XX ZZZZZZZZ!!???

[gale]

[IMG]http://www.nmia.com/~dgnrg/ac_clutch1.jpg/IMG]

http://www.nmia.com/~dgnrg/ac_clutch1.jpg

Mine is identical to this one from Bentley's (Seiko-Seiki) except it has a vee-groove pulley instead of the serpentine. I can't exactly call what I did a rebuild, rather a minor re-surfacing job. The clutch was functioning but would screech if engaged above 1500 rpm. There is supposed to be about a 0.020" gap between the drive plate and the pulley surface (when disengaged). Mine had about a 0.080" gap. What I did is:

1. engage the clutch
2. remove the retainer bolt #1
3. remove the belt
4. remove the drive plate #2, it is splined to the compressor shaft and wiggles off
5. remove the snap ring #3 (a bitch with the compressor in the car)
6. pry off the pulley #5 with a modified gear puller, was a snug press fit but did not require alot of force to remove
7. chucked the pulley #5 in a lathe, indicated the runout to within +/- .0005", & took approx. 0.005" skim cut off of the friction surface (it was badly worn & grooved)
8. jitterbugged the friction surface of the drive plate #2
9. re-assembled. There is a shim washer (not shown) on the compressor shaft behind the drive plate. I did a measurement without the shim and it was too tight. I machined a 0.010" thick shim & re-attached the drive plate and now it measures 0.013", a little tight but doesn't scrape when free-wheeling.
10. put it all back together & it works great, with just a slight chirp when it engages above 3000 rpm, but bare hear it below that.

I didn't mess with the solenoid business at all, seemed to be working fine.

If yours is messed up in another way than what mine was, there would be no consequenses if you removed the belt, just make sure you don't engage it after that or it could fry the clutch solenoid if it's not toast already.

[Boggie1688]

Thanks...very very much for the picture...OMG what a big help on what the AC compressor actually looks like...big help to me and my dad...lolz...

Yea we had the same screeching noise...until we changed the belts...now we just get this weird clickin clunkin noise....I have a feelin its the clutch bearing...You think if i take the bearing out and go down to the local hardware store...they will have a replacement? Can I just throw any bearing in there? that will fit?

Lastly...about removing the belt from the AC compressor...if I take the AC compressor out of the belt...will I need to switch to a smaller belt? Yea right? otherwise i'll have slack all over the place...? right?

[Boggie1688]

Aites I got under the hood anyway...and I managed to remove just the cover of the compressor clutch...and what is left is the pully with the belt around it...and I wanna get the pully out...but I cant get the damn belt off...and I really have no idea how...and my dad was saying that I need to remove the tensior then that will take the tension of the belt soo i can easily take it off....which makes sense...but the god damn tensioner won't come off!! I dunno what screws I'm suppose to take off...what I'm not...and all in all its seems like the damn thing is stuck there like glue! HELP!

[gale]

Yeah, I know what you mean about getting the belt off. I just put all new belts on mine maybe a year ago & the a/c belt was too tight to pry off of either pulley so I sacrificed the near-new belt & cut it off with a pair of dikes & bought a new one the next size longer when I put it back together. There isn't much travel on the adjuster to accomodate a longer belt.

The bearing feels a bit gritty on mine but doesn't make any noise (so far) but I have it in the back of my mind I need to replace it. When you get the pulley off, you'll see that the bearing is staked so you'll have to grind the nubs off with a dremmel tool before pressing the bearing out. Going back together you'll need to stake the bearing again with a punch or maybe press it in with some semi-permanent Loctite.

Hardware stores won't be any help finding a bearing & neither will Autozone, Pep Boys, Checker, etc. Maybe try Napa or for sure, check the Yellow Pages for an industrial bearing supply house. They'll be able to match it up. Maybe press the old one out & look for a bearing number on the side of the outer race & plug the number into Google & find one on the web. If you have a set of calipers, measure the o.d., i.d., & thickness in millimeters & that will give you the generic size/part number, something like 80x50x20 or such (just making up an approx. size from memory). I'm quite certain it's a ball-type bearing (as opposed to a roller bearing), double-sealed. Get a Timpken or other high quality brand. Bearings come in different grades of quality based on how many service hours they're rated for so don't scrimp.

Does yours have a single serpentine flat multi-toothed belt or do you have individual belts for the various accessory drives? Mine has a single dedicated belt for each component so I can take them off individually, but if your a/c belt also drives the p/s or alternator or water pump, you'll have to ballpark a shorter belt & means to tension it. Maybe wrap a rope around the grooves to simulate a belt, mark where the end meets, & lay it out & measure the total length with a tape measure & should be within a size or 2 of the right size. If you don't have a means to tension a shorter belt when bypassing the a/c compressor, then your hosed. Mine doesn't have any idlers/tensioners, just direct-drive, one seperate belt for each component & they each have their own manual adjustment.