A/C Questions
Thread Starter
Safety Car
Joined: Aug 2013
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From: Minneapolis Mn
A/C Questions
I found something yesterday on my 86 convertible that doesn't seem right regarding the A/C. It's a manual shifter, but I don't think that should make a difference. I can't find anything on this in the FSM as it only covers the electronic A/C controls, while I have this:
Background: I had the Freon charged last month in prep for a road trip but didn't use it on the trip. The other day, drove it when it was foggy out and used the defroster with heat up to clear the windshield. When I got home, I moved the heat control to cold after shutting it off as it's otherwise been hot here. Yesterday I went to drive it, I had a bird like chirp and it barely ran when started.
While trying to track down the chirp, I found the A/C compressor was running while the heater control was on defrost and the temp was on the coldest setting, even when you first start the car.
First question: does the A/C normally run with the controls in those positions?
Second question: When the A/C is running, it chirps like a bird but only when the A/C is running. When it's not engaged, no noise. Is the chirp normally in the A/C clutch in a scenario like this or is it in the compressor?
Thanks for any help.
Paul
Background: I had the Freon charged last month in prep for a road trip but didn't use it on the trip. The other day, drove it when it was foggy out and used the defroster with heat up to clear the windshield. When I got home, I moved the heat control to cold after shutting it off as it's otherwise been hot here. Yesterday I went to drive it, I had a bird like chirp and it barely ran when started.
While trying to track down the chirp, I found the A/C compressor was running while the heater control was on defrost and the temp was on the coldest setting, even when you first start the car.
First question: does the A/C normally run with the controls in those positions?
Second question: When the A/C is running, it chirps like a bird but only when the A/C is running. When it's not engaged, no noise. Is the chirp normally in the A/C clutch in a scenario like this or is it in the compressor?
Thanks for any help.
Paul
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
One more thing, don't know if it makes a difference or not but the car had been converted to the newer Freon (R132?) before I bought the car and there's a sticker under the hood about that. That's what the shop used in charging up the A/C.
Team Owner
Joined: Sep 2003
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Compressor does 'RUN' when in defrost mode. I'm surprised it's not mentioned in the FSM. Very early GM/Harrison compressors didn't and I don't recall when that was changed but if the compressor runs in defrost I believe all is well.
The "chirp"? I had one for nearly 200K miles with an R4 in a CK truck and I believed it to be the clutch. Compressors 'knock'!! If it's cold and runs I don't know that I'd mess with it. An 'air gap' issue I'd expect.
The "chirp"? I had one for nearly 200K miles with an R4 in a CK truck and I believed it to be the clutch. Compressors 'knock'!! If it's cold and runs I don't know that I'd mess with it. An 'air gap' issue I'd expect.
Last edited by WVZR-1; Sep 6, 2015 at 07:37 AM.
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
Appreciate the info. If it is the A/C clutch, I just may try replacing that myself this winter while I store it. Watched a Youtube on it last night, didn't look to be beyond my tools and ability.
Team Owner
Joined: Sep 2003
Posts: 25,393
Likes: 2,741
I wouldn't rush to 'throw parts at it'. Maybe do some reads about 'burnishing' and 'air-gap' regarding AC clutch performance.
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
Totally agree at not throwing parts at it needlessly. Just commenting that it looks like the clutch could be something I can do if that's the problem. Still have not confirmed it the problem or not.
