On Friday, I was taking my car on a long drive when I noticed smoke from under the hood. It was raining, hot and humid so I was using the AC on defrost to clear the windows. The smoke I saw was coming from the AC compressor and appeared to be emanating from the front. I cut off the belt so I could finish my trip. Now with the belt removed, the compressor no longer turns freely, though it does still turn with some effort while making a scraping noise.

I would like to fix the AC since I find it valuable for defrosting purposes, plus my wife doesn't like to roast in my black car on a 100 degree day. I noticed that Rock Auto lists an air conditioning compressor bearing for $27:

NATIONAL Part # 5001KFF Ball Bearing; Bore=1.5748", Outer Diameter=2.4409", Width=0.9449"
Sanden SD-510
Sanden SD-708

Would this be likely to fix my problem? I'm sure I could round up a used, functioning Sanden compressor for not too much money, but isn't it likely that it would also have an old, worn bearing anyway?

 

I doubt it's just a bearing that caused it to seize. Replace the compressor and flush the system, good idea to replace the drier too.

I have 2 compressors laying around, 5 bucks plus shipping and you can have one.

 

Thanks for the offer, K-Tune. I'll be happy to take one of those compressors off your hands. I'll send you a PM with my address so you can give me a shipping quote.

Would it be smart to install a new bearing in one of those used compressors to increase the chances of reliability? I don't know much about AC charging/evacuating so I'll be paying somebody to do this for me. I'd like to have as much confidence as possible in the compressor I'm installing so I don't have to do this job multiple times.

 

It's too much work when you can pick up a working unit for pennies on the dollar. In most cases, these are the most desirable units to obtain, since the remanufactured ones you buy at a parts store have a reputation for failing prematurely.

If you're interested in rebuilding one, the FSM has a great breakdown of the components I'd rebuild one just for the experience

If you're also interested in learning how to evacuate and recharge your system with a safe and cheap alternative refrigerant, check this thread out:
https://www.rx7club.com/2nd-generati...igerant-964688

You'll spend the same if not a little more money(for the tools if you decide to buy instead of borrow), but you'll now have the knowledge and could probably make a few quick bucks on the side helping your friends out

 

if u are doing it for experience, then yes

otherwise, no, cuz there are so many working units out there that u can get for a few bucks.

 

I took a closer look in the area around the compressor today and I discovered some strange black material that obviously flew out of the compressor from behind the pulley when it failed/seized. It has dried rock hard and glossy black, almost like a plastic resin of some kind. It does not chip off the aluminum mounting bracket nor even the nearby oil cooler hoses that it has accumulated on. What is this stuff?

 

Incidentally, if anybody else has a functioning Sanden-type compressor they'd like to sell me, please shoot me a PM. K-Tune checked his and they were both Nippon Denso. I'll also check the Classifieds.

 

the black stuff is likely the belt, when the compressor seizes the belt has to keep going and like doing a burnout on the street the belt begins to melt from the friction. you can see the clutch has been overheated and cooked the zinc off the front of the compressor clutch as well.

i don't even think any companies rebuild these compressors, just about anything RX7 related is black balled from reman and even parts stores now. i have to special order spark plugs, brake rotors and pads for second gens.. at least they still stock drive belts, for now.

 

This is why I've started stockpiling key replacement parts for the shelf such as clutch and brake hydrolics. Not so much to get a part, but to fill in the down time while waiting for that special order part to arrive.

Specific to this thread, the only difference between the Sanden compressors on an S4 and S5 is the end cap. So I have an a remanufactured Sanden compressor for my S4 on the shelf, and an S5 end cap.

 

There are a number of "remanufactured" Sanden SD708 compressors on eBay in the $100-150 range, and a bunch of "brand new" equivalent compressors in the $300-350 range, some evidently not actually made by Sanden, on eBay. One offered for $350 by a "BuyAutoParts.com" looks like a genuine Sanden SD708 in the photo, unless it is counterfeit. Are these all pretty much junk? I'd love to be able to get a brand new part since I plan to keep this car a long time. I wouldn't rule out the $350 if it was going to last five times longer than a used compressor I'm going to be buying from somebody's 150,000 mile car. Any first-hand experience with these options?

 

Sanden does not recommend rebuilding their a/c compressors. I have not found piston o-rings anywhere, but you can buy new clutches and gaskets. Make sure the replacement compressor has the correct manifold on it. They used the same compressor in lots of cars and the only differences are the mounting bolts and manifold (where the lines attach).

 

Yes, I read that on the Sanden website about them not recommending rebuilding. I'm wondering when the SD708 went out of production. In other words, if I plunk down big money for a NOS SD708 with the correct manifold and mounting bolt arrangement, might it be 15 years old? I assume the manifold and mounting bolt setup is not easily swappable from my burned out compressor to a new one, right?

 

6 bolts, existing manifold and mounting set up (end housing) come off, end housing of your existing one goes on, reinstall with the same 6 bolts. That's it.