240 A/C Resurrection Advice

I have a 91 240 wagon that my son is currently driving. Air conditioning on the car never worked since we've owned it (honestly never looked into it), however all components are intact.

He was driving to work a few weeks ago, and the compressor bearing must have seized, which burned the a/c belt and then stopped the P/S pump from pumping.

My question - because compressor seized up, does that mean it likely killed the rest of the system, or simply stopped turning?

I'm happy to tear into the system and replace components - compressor (obviously), receiver/dryer, expansion valve, o-rings.

Any advice on how to go about this job? Assume I have to clean out the lines, condenser, evaporator, etc. Seems like the later model a/c systems are the ones to have, so why not get it running?

A new compressor, receiver dryer, orifice tube, and a flush job is in order. Shoot it up with Envirosafe 12A refrigerant. I would only disturb orings that need to be disturbed, wouldn't go replacing them on principle.

Thanks, but still replace o-rings on stuff replaced (compressor, r/d, etc.) right?

Of course

kyote said:

A new compressor, receiver dryer, orifice tube, and a flush job is in order. Shoot it up with Envirosafe 12A refrigerant. I would only disturb orings that need to be disturbed, wouldn't go replacing them on principle.

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I agree. Definitely don't skip the flush in this instance. The compressor likely shot a bunch of metal through the system. You'll see good amount of it in the orifice tube, but it's going to be everywhere. Plus, you'll want to remove all the mineral oil. Replacing with ester is my preference because it will work with R-134a and not get ruined by any residual mineral oil like PAG would.

I have no experience with Envirosafe and prefer to convert to R-134a, but I know others will disagree with that part. OP, you have the updated R12 system, so R-134a should work pretty nicely in there if you choose. I have R-134a in a dealer converted '89 240 which is really just a compressor and TXV adjustment on the old R12 system. It blows cool enough to be comfortable all summer (midwest). It just doesn't freeze us out when I turn the knob up to max.

Bearings can seize without the actual compressor being destroyed (pretty common actually) so pull the bearing and check the compressor to see if it's actually seized or just the clutch bearing. All of the parts are replaceable and easy to come by. I can't recommend enough to replace every seal, there's not that many of them and you'll likely need new hoses anyhow. Need new receiver/drier, check the condenser for any leaks, can be replaced for ~$100. Definitely flush the system, even if you're using the R-12 replacement. Vacuum and fill the system to spec. and enjoy!

When I got the a/c going in my 93 it needed all the suggested parts like the compressor, and accumulator, also I replaced the orifice valve with a variable orifice valve. The VOV helps the system run better with the high demand in the hot weather. Another point, if your car doesn't have a pusher fan it's very important to add one. If your car does have one be sure to test it.

The compressor I bought was a four seasons one from FCPEuro which was larger and much better made than the original one.

Thanks for all the feedback. I just read the long, somewhat recent thread on A/C resurrection and it looks like that Sanden compressor and R134a conversion is a good, reasonably affordable route. I'll replace accumulator, orifice valve, and o-rings while I am at it. I have a friend with the a/c equipment so we can pull vacuum and put in the refrigerant, but first I'll take car to a shop and have it evacuated in case any R12 is still in there (doubt it). Will clean everything out, too.

I checked the compressor today when my son stopped by, and it now turns by hand...when it ate the belt it would only turn partially until it locked. In any case a replacement seems prudent.