Topic: A/C Clutch
in Forum: C3 Cooling and Heating Systems
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On the way home I noticed a smoke coming out from under the hood. The compressor clutch had stopped turning and the belt was smoking. I cut it off and drove it home. Does this mean a new compressor or does the clutch need replacing? Is it bet to buy remanufactured , or new OEM?
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You should replace the compressor. It easier and more cost effective in the long run. A reman compressor will work just fine for most applications. I recommend taking it to a service facility to remove the R12 and replace it after the compressor is replaced.
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Duncanville, TX - USA
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Were you running the A/C at the time? The bearing in the pulley can seize, and lock it down, whether the A/C is on or not. But, if you wern't running the A/C at the time, then it couldn't very well be the compressor locked up.
The bearing can be replaced fairly easily, if that is all that it needs. With the belt off, does the pulley turn? If it does not, then the bearing may be the only problem. If the clutch does not turn, then the compressor is locked, and will need to be replaced. If the pulley won't turn, but the clutch does, then you just need a bearing. I've seen locked up bearings kill an engine before smoking the belt!
As far as replacement compressors, I've learned thru the years that a new one is always more reliable in the long run. Remans don't seem to survive very long, compared to new. Just my observation...
I have a locked up compressor on my '74 at this time. I will buy a new compressor, and swap the guts, so I can keep my "original" compressor. That's just the NCRS in me!
The bearing can be replaced fairly easily, if that is all that it needs. With the belt off, does the pulley turn? If it does not, then the bearing may be the only problem. If the clutch does not turn, then the compressor is locked, and will need to be replaced. If the pulley won't turn, but the clutch does, then you just need a bearing. I've seen locked up bearings kill an engine before smoking the belt!
As far as replacement compressors, I've learned thru the years that a new one is always more reliable in the long run. Remans don't seem to survive very long, compared to new. Just my observation...
I have a locked up compressor on my '74 at this time. I will buy a new compressor, and swap the guts, so I can keep my "original" compressor. That's just the NCRS in me!
Joel Adams
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Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
You can get new OR remans at most parts houses(NAPA, Pep-Girls, Auto-Zone)...or you can get remans for just about any of the Corvette parts vendors.
Joel Adams
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Vette(s): 1972 Coupe, Small Block, A.C., Tilt-n-Tel, Deluxe Interior, 85K miles.
Last week while driving my '72 coupe I had noticed smoke from under the hood only one of the A.C. hoses had sprung a leak and was spaying colant on the ehaust. The wierd think is the A.C. was not on as it was a cool day. My question is...Should the system be pressurized with the A.C. off? Any suggestions out there?
Buckeye Fan
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#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
The A/C system is indeed under pressure whether or not it is operating. Normal(full charge) R12 refrigerant pressures closely follow ambient temperatures, so, if it's 80deg. outside, you'll have around 80-90psi in the system, if it has not been turned on. Once you start driving, and the underhood temps rise, the A/C system pressure will also rise accordingly.
A hose can go at any time, regardless of if the A/C is on or not.
A hose can go at any time, regardless of if the A/C is on or not.
Joel Adams
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Can you buy a "clutch rebuild kit?" 
How hard is it to rebuild?
How hard is it to rebuild? 
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MICK - C3VR Lifetime Member #113
The bearing in my A/C clutch did the same thing a few years ago. Luckily I was driving the car with no hood so I saw where the horrible noise and smoke was coming from ( I was having some air brushing done under the hood at the time.)
Anyway, I pulled the clutch assembly off and made sure the compressor still turned, which it did. I was able to get a clutch and bearing assembly at Auto Zone of all places. I think it was around $50 to $75 (much cheaper than a new compressor.)
It worked perfect and I didn't even have to take the compressor off the car.
As for the R-12, all of mine was long gone before I bought the car. I retro-fitted it with R-134a about 6 years ago and it's still working today. Maybe I got lucky...
Good luck in what ever you choose.
in Forum: C3 Cooling and Heating Systems
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