A/C Compressor Clutch

[AaronM]

Well, my A/C started working only sporadically and when it works, it works fine, but when it stops cooling there's also a nice screeching noise from the A/C compressor clutch and if I watch I can see that the compressor isn't engaging.

Does changing the compressor clutch require that the compressor be removed from the car or could I replace it without having to empty and re-fill the system?

Also, anyone know where I can get a replacement?

[bscpanther]

Aaron, I didn't even know you could replace just the compressor clutch but I'm not the most knowledgable when it comes to the a/c, somehow mine works. If you can just replace the clutch, I highly dought you will be able to leave the compressor in the car. What I do know is that if it comes down to you getting a new compressor go to www.*************** I have been using that place for years and they save me big $$$. I haven't seen prices close to theirs. Better still is their service. You could also check out ebay for a quick fix but thats always a gamble.
good luck

[AaronM]

Thanks, but I finally tracked down the NipponDenso part Number (10P15E) and found a few places to source a clutch for it. Some places also have just the clutch solenoid, and I'm debating replacing only that since I have a hard time believing that the rest of the clutch would wear out too. I suppose that I'll just have to get the car in the air and get the current clutch off to find out.

Thankfully with Seattle weather the A/C isn't terribly necessary up here.

Interesting thing is that the '86-'89 Honda Accord used the exact same NipponDenso compressor (same part number). If I look it up for an old Accord, a complete rebuilt compressor is $291.39, but if I look it up as a Porsche part, it's $362.39. I'm checking things like the size and number of grooves on the pulley right now, but it's tempting to just buy the part for the Accord and Frankenstein it.

[nize]

are you sure the belt isn't slipping?

[AaronM]

Originally Posted by nize

are you sure the belt isn't slipping?

Metal-on-metal screeching. Definitely not belt noise. It isn't the compressor internals since when it does work, it works perfectly and silently, which leaves me with the clutch.

I wish it were just the belt.

[nize]

try pouring some oil in there ?

[AaronM]

Originally Posted by nize

try pouring some oil in there ?

That would just make it slip worse. I think that what's most likely is that the solenoid has gone weak and isn't maintaining full pressure against the clutch surface.

[nize]

here's some related stuff;
http://forums.rennlist.com/rennforums/showthread.php?t=368698

http://forums.rennlist.com/rennforums/showthread.php?t=360749

http://forums.rennlist.com/rennforums/showthread.php?t=353457

http://forums.rennlist.com/rennforums/showthread.php?t=277509

http://forums.rennlist.com/rennforums/showthread.php?t=266612

[Lawrence Coppari]

Sounds like your clutch is acting up. I have changed my clutch with the compressor in the car so it can be done.

About 6 years ago I replaced my Nippon with a Sanden because six months after putting a new clutch on it, the front seal began leaking. Works just fine. You might think about alternate refrigerants. R12 is expensive. My old Mercedes that I sold last summer used the alternate refrigerant for at least 10 years. It's been in my 944 since I switched to the Sanden.

[AaronM]

Originally Posted by Lawrence Coppari

Sounds like your clutch is acting up. I have changed my clutch with the compressor in the car so it can be done.

About 6 years ago I replaced my Nippon with a Sanden because six months after putting a new clutch on it, the front seal began leaking. Works just fine. You might think about alternate refrigerants. R12 is expensive. My old Mercedes that I sold last summer used the alternate refrigerant for at least 10 years. It's been in my 944 since I switched to the Sanden.

I'm already running Duracool (a propane-based refrigerant with slightly better characteristics even compared to R12, and it positively blows R-134a out of the water). Runs about $8.50 per can, which is equivalent to 1 lb of R12.

I'm back and forth on replacing the entire compressor since it always seems silly to replace something because it "might" fail. On the other hand, it's a 21 year old compressor... On the other hand, the cost of a rebuilt compressor for an A/C system that I don't really need is just about what it would cost me to pick up an '82 Honda motorcycle...

Decisions, decisions. Someone slap some sense into me.

[nize]

get a motorcycle, then we can go riding !

[Lawrence Coppari]

As I recall the Sanden conversion cost me about $350-400. Must be nice and cool up there in Washington. I wouldn't have replaced mine except it's too hot around here. Drove it to several DEs in Atlanta area six summers ago with no AC. I had to drive in a tank top with a spritzer bottle spritzing myself to keep anywhere near cool. Other motorists got a chuckle out of it.

I use Duracool too.

On the 1980 Mercedes I sold last summer, it developed a slipping AC clutch. Clutch did not squeal but would smoke as the oil that had oozed out of the compressor after 26 years burned off due to frictional heating. Bought a rebuilt compressor for it. It was a very common GM compressor (must have weighed 35 pounds at least) so it cost less than a C note.