I may be able to purchase an 85 635, 5-speed, "greenish grey?", ~200k mi., lowered (no specifics yet), from the 3rd owner who has all service records for $4k or possibly less.

The car belongs to the fiance of our very cool car insurance gal, so the source is rather trustworthy, but I have not seen the car yet.

The big issue is the non-working a/c. My husband successfully tackled the a/c and the conversion to R134 in one of our trucks (not a BMW, I know) and we are not incompetent with wrenches nor afraid of new and unusual automotive challenges.

Is this a "big ticket" item and a giant nightmare? Where would we source parts? Any ballpark figures on part costs (yes, I know that it would depend on what was wrong with it...)? A grand? Two grand? A lot more? A lot less? I've searched and either I'm just not using the correct terminology or there isn't much to be found so far.

Any other wisdom you'd be willing to impart about looking over an 85 6 would be greatly appreciated as well.

Thank you in advance.

I am in the same place, I have an 87 635csi, all my fans work but the a/c is never cold. I know its using freion and i would need a freion charge but that isnt allowed due to regulations. I would need a conversion right that would cast about 100 to fit it and than XXX.XX$ for the new unit and rigging up. Any ideas also for me ?

Realistically, I doubt it's just a recharge, the problem with the 635s is that the later cars used a dual AC system, and it's complex and can be very expensive to repair.

I've seen them with bad expension valves, compressors, condensors, etc... Also, the compressors on 80s BMWs generally do not take well to R134a, so figure at least you're in for a compressor and a receiver/drier..... I'd consider a pre-buy at a BMW shop to get an idea of what you're in for.

Also, with 200k on it, $4k is high unless the car is MINT.

I may be able to purchase an 85 635, 5-speed, "greenish grey?", ~200k mi., lowered (no specifics yet), from the 3rd owner who has all service records for $4k or possibly less.

The car belongs to the fiance of our very cool car insurance gal, so the source is rather trustworthy, but I have not seen the car yet.

The big issue is the non-working a/c. My husband successfully tackled the a/c and the conversion to R134 in one of our trucks (not a BMW, I know) and we are not incompetent with wrenches nor afraid of new and unusual automotive challenges.

Is this a "big ticket" item and a giant nightmare? Where would we source parts? Any ballpark figures on part costs (yes, I know that it would depend on what was wrong with it...)? A grand? Two grand? A lot more? A lot less? I've searched and either I'm just not using the correct terminology or there isn't much to be found so far.

Any other wisdom you'd be willing to impart about looking over an 85 6 would be greatly appreciated as well.

Thank you in advance.

You should figure on a grand for DIY. Alot more if a shop does it. Hopefully it'll be alot less. It all depends on what condition the AC system is currently in. The hardest part is that the evaporator and expansion valve is hidden tightly under and behind the dash. I have some new AC parts available and also some used parts too if you need. Hope this helps.

i remember a while back you said that you would want to find a six.you helped me by posting pics while selling my 1st one.just bought a digital camera and hope i can figure out how to post.
on my 86,it is still set up for R12 and the compressor still kicks on,but no cooling and watching the sight glass there doesn't appear to be any flowing of freon.so i'm in the same boat as you.i want to do the conversion to R134 and know at the least,it will require the dryer.i'm wondering if a clogged expansion valve is causing my current problem.how do you get to,diagnose,or replace the valve?

Well, given a little bit more digging, deep contemplation and the responses here, I think I'll pass on this car. Apparently the exhaust is off the car on top of the non-working a/c. I'd rather have one I can drive now, and I think for 5-6 grand (my vague allotted budget), I should be able to find one. I have two project cars already, and though I'm a glutton for punishment, I should not allow myself a third. :)

The search continues... :(