Black goop coming from A/C compressor clutch?

My 2002 Liberty Sport has about 110K miles on it. I bought it used.

I don't know if the A/C compressor has ever been changed, but I saw some mysterious black material that looked like acrylic spray paint splattered on the alternator a few months ago.

I didn't know what it could be and forgot about it. But the A/C quit working last week and I drove for 20 minutes or so before turning the A/C selector switch off.

I smelled a funny odor and I thought I saw smoke coming out from under the hood.

When I stopped, the A/C compressor clutch had quit working and there was a lot of the black stuff splattered on the alternator fins and on the serpentine belt tensioner and the black splatter had radiated all around the A/C clutch, even onto the sound absorbent material under the hood.

The clutch bearing is worn out too, the A/C clutch flops around about

1/8th of an inch and makes a grinding sound as the engine runs. I can see shiny little metal flakes that have come off the bearing...

The electrical coil in the A/C clutch has also burned out...

I can get a new compressor with clutch for $250 to $300, but I was wondering what really caused all that black stuff to splatter all over the place.

Could a compressor seal have blown out simultaneously with the clutch failure and the coil burning up?

Reply to
little man upon the stair
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Reply to
L.W.(Bill) Hughes III

I just rebuilt my compressor and the rule of thumb is that if the compressor shaft is hard to turn or frozen you might as well spring for a new one. The a/c oil does a good job of coating the underside of the hood just above the a/c clutch if it's leaking. Any play AT ALL in the clutch means a new clutch - period. Since it turns anytime the engine is running, you're a pedestrian until you get a new pulley and bearing in there but whether the compressor is salvageable or not is still an open question. If you can turn the compressor shaft - not the clutch - with a suitable wrench on the nut at the end of the shaft note whether it turns smoothly with no rough spots. If not, forget it - it's toast. It will cost you as much or more to have it rebuilt as a new one will anyway. If you elect to go back to the old 4/60 system (4 windows open at 60 mph) you still need a working pulley wheel where the a/c clutch was before you can drive it. I went to the junk yard and got a whole compressor with a good clutch bearing to serve while I had the one out for repairs. I left the clutch disconnected as I had no idea what shape the compressor was in but I needed the pulley for the the fan belt. My only problem was blown seals but yours sounds sounds like a basket case - get a local chop to render an opinion but I'd bet you're looking at a new compressor at the very least. If the compressor shaft is frozen or rough turning, you're in for a a bunch of new parts - the condensor, receiver/dryer, expansion valve and possibly the evaporator core are almost certainly full of bits and pieces. Big bucks time.

Reply to
Will Honea

Thanks for answering my query, Will.

Actually, the compressor shaft turns, but I have no idea how much force it should normally take to to turn it.

But does the oil dry like black acrylic paint, or does it stay oily? I would expect it to stay oily.

Maybe the dried black stuff is a mixture of neoprene oil seal and compressor oil?

According to my web searching so far, there are *no* Sanden A/C compressor clutches available separately, and one owner on another forum said that parts would cost around $200 if bought from a Jeep dealer.

A new compressor with clutch is about $250. Throw in the accumulator and the o-ring kit and expansion orifice and I'm looking at $296.00 from Discount AC.

I'm wondering is whether there is still any refrigerant in the system. I don't have a pressure gauge.

I don't like the idea of taking my vehicle to any of the local service shops and paying an eager young kid to have the refrigerant sucked out if there isn't any refrigerant left in there.

I suppose I will find out when I open up the system to install the new compressor and dryer...

Actually, I have driven almost 200 miles with the A/C compressor clutch grinding away and making a bad smell, so I can get around town on my little errands.

Even though the clutch hub bearing is toast, the serpentine belt tensioner keeps the belt tight. =A0

I'm a fairly good mechanic and have lots of good quality tools.

I've been doing all my own work for almost half a century, ever since a mechanic at an Oldsmobile dealership tried to con me into taking my

1951 Rocket 88 to his house so he could rebuilt my hydramatic.

It seems like the u-joints were worn out and they were making a clanking noise, but the crooked mechanic wanted to charge me a lot of money, claiming I needed a lot of unnecessary work done. He claimed that the transmission had an "exploded rear drum"...=A0

If I started telling stories about all the times mechanics have tried to cheat me, I'd be typing for hours.

After *many* unsatisfactory experiences with dishonest mechanics, I don't like to be treated like a fool anymore. So I stay away from the dealerships and independent mechanics.

The compressor shaft does turn, but I have no idea of how many foot pounds of torque it normally takes to turn the shaft. I guess I will know whether there's any oil and refrigerant left in the system when I open it up next week.

I understand the moral implications of releasing refrigerant into the environment, but, if there isn't any refrigerant left in the system, I guess I won't burn in Hell for opening it up...

Reply to
little man upon the stair

It will take a fair amount - remember that you are actually turning a working compressor. My rule of thumb is that if you can turn the shaft with a wrench without a whole lot of grunting that is a good sign. Mine spun pretty well with a quarter in drill driving it but the drill was straining at speed. What you really want to know is if it turns smoothly. That's a little hard to tell because of the pistons loading up but those will be fairly soft bumps. Anything like a sudden sharp bump is cause for suspicion. Just a thought... Your's sounds like it was burning the clutch. That is a metal-to-metal contact with very minimal slippage and any slip will get VERY hot in a hurry. It also gets noisy - think irritated wife noise, high and screeching.

On mine, it just collected dirt and turned nasty. You may have melted the potting compound out of the windings. In a way, that's good because that much heat would have cooked the bearing.

I used

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I called and they were pretty helpful. Theyare based in Phoenix, so I expect they see a lot of a/c action ;-)

Three suggestions: 1. Advanced Auto here has a rack of a/c service kits and small parts. One is a cheapy filler with a low side connector, guage, and can tap. Under $10.

  1. Harbor Freight sells a full manifold set for about and frequently puts it on sale for .99.
  2. Put on a GOOD set of long gloves and safety glasses, then use a long screwdriver to just bump the low side valve - if it squirts anything, the system is charged to at least some degree.

I recommend #2. Harbor Freight has a web site you can order from. If you intend to do any serious work on this thing you will need the gauge set and their cheap one performs just as well as my Snap-on set. Even that one has paid for itself several times over in the years I've had it.

Wear good shoes and keep a water bottle handy - that system won't last long. Also add a new serpentine belt to you cost ;)

See above - you're really just looking for smooth operation. You'll feel the bumps from the pistons if the system is charged but you can feel the difference between compression and mechanical roughness.

You may get by with replacing the clutch in the vehicle without opening the system if you can find one. Make sure you have a decent puller and a good set of snap ring pliers. I'd bet that it would be more work than it's worth, though. No need for the drier and the other stuff if the compressor is OK and just needs a clutch. New o-rings are a must for anything you disconnect, though.

There are several sites online where people have rebuilt/replaced compressors and the Sanden manuals are available online in pdf format.

Reply to
Will Honea

I would do *something* as soon as possible, before driving much more. If that pulley, bearing, or whatever comes apart while you're driving, you could be looking at more damage to unrelated things under the hood.

Reply to
Dale Beckett

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