86 Manual A/C Help
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
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From: Minneapolis Mn
86 Manual A/C Help
I have an 86 with the manual a/c controls and looking for a little help. I've attached a picture of the controls.
First, my FSM is missing the section on the manually controlled a/c, have for the electronic but not the manual. Does anyone have it in your FSM? If so, could you scan the stuff on the manual controlled part along with diagnostics on that system and email it to me?
Second. I had the R134A charged last summer and it was working when I put it away for the winter. Last weekend I replaced the compressor clutch and when done the compressor clutch won't engage. .015" airgap, swap went well, everything seems right but the clutch is not engaging. I'm sure it's something dumb, but I haven't thought of what I've done wrong and without diagnostics it's a little hard to find the problem. I should have ran it before doing the a/c clutch to insure it was still working, but didn't think of it and didn't test it before removing the old clutch. Any ideas?
Thanks for any help and especially if you can scan the missing parts of the FSM. PM me and I'll send you my email address.
First, my FSM is missing the section on the manually controlled a/c, have for the electronic but not the manual. Does anyone have it in your FSM? If so, could you scan the stuff on the manual controlled part along with diagnostics on that system and email it to me?
Second. I had the R134A charged last summer and it was working when I put it away for the winter. Last weekend I replaced the compressor clutch and when done the compressor clutch won't engage. .015" airgap, swap went well, everything seems right but the clutch is not engaging. I'm sure it's something dumb, but I haven't thought of what I've done wrong and without diagnostics it's a little hard to find the problem. I should have ran it before doing the a/c clutch to insure it was still working, but didn't think of it and didn't test it before removing the old clutch. Any ideas?
Thanks for any help and especially if you can scan the missing parts of the FSM. PM me and I'll send you my email address.
Team Owner
Joined: Sep 2003
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Manual AC is mixed with the AC information in 1B with an image of the control at maybe 1B-2. See if you can just leaf through that section and find the information.
The electrical aspect of C60 is in the 8A section as is also the vacuum routing in more detail, look in 8A-62 and the the following.
You'll need NOT to "spit" I'd think for the basic operation diagnostics.
The electrical aspect of C60 is in the 8A section as is also the vacuum routing in more detail, look in 8A-62 and the the following.
You'll need NOT to "spit" I'd think for the basic operation diagnostics.
Last edited by WVZR-1; Jan 27, 2016 at 10:01 PM.
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
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From: Minneapolis Mn
The car was converted to R134A before I bought it. It's got a large sticker on the underside of the hood stating that.
I've got the blue looseleaf manual like a service department would have. Mine goes from page 1B1-7 to 1B-7, nothing in between. There's also nothing in section 1A under Heating and Ventilation. Never came with the manual (bought used the other year).
I hadn't found a leak but without gauges and no knowledge on how to cycle the compressor, it's hard to tell what the cause of the non-engagement of the clutch is being caused by.
I've got the blue looseleaf manual like a service department would have. Mine goes from page 1B1-7 to 1B-7, nothing in between. There's also nothing in section 1A under Heating and Ventilation. Never came with the manual (bought used the other year).
I hadn't found a leak but without gauges and no knowledge on how to cycle the compressor, it's hard to tell what the cause of the non-engagement of the clutch is being caused by.
Race Director
Joined: Mar 2015
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The car was converted to R134A before I bought it. It's got a large sticker on the underside of the hood stating that.
I've got the blue looseleaf manual like a service department would have. Mine goes from page 1B1-7 to 1B-7, nothing in between. There's also nothing in section 1A under Heating and Ventilation. Never came with the manual (bought used the other year).
I hadn't found a leak but without gauges and no knowledge on how to cycle the compressor, it's hard to tell what the cause of the non-engagement of the clutch is being caused by.
I've got the blue looseleaf manual like a service department would have. Mine goes from page 1B1-7 to 1B-7, nothing in between. There's also nothing in section 1A under Heating and Ventilation. Never came with the manual (bought used the other year).
I hadn't found a leak but without gauges and no knowledge on how to cycle the compressor, it's hard to tell what the cause of the non-engagement of the clutch is being caused by.
if you just charged it might have a leak did you spit yet?
Last edited by antfarmer2; Jan 27, 2016 at 10:09 PM.
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
I'll be making up some dishsoap solution again. I did it last summer after the system was recharged and didn't get any indications of leaks on any of the fittings at the time, I'll have to do it again. May be a couple of days, have a family issue come up I'm dealing with.
The wife mentioned something that might apply - is it too cold out for the a/c to run? It's only been in the 20's as a high lately.
Thanks
Last edited by hcbph; Jan 28, 2016 at 05:47 AM.
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Pro
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From: the confused state CT
I'm sure WVZR-1 has you on the right track. Here's a couple items I would do as a quick check. Now that you have the pressure switch locations use a test light to check for power at the back of the clutch for power. If there is no power remove the low pressure switch and jump to see if it cycles.
It is a sealed system so if you had to recharge it there is a leak somewhere. The leaks can sometimes be a pia to find. I would also visually check the condenser in front of the radiator to see if you can see a sign of a leak such as dampness.
Gary
It is a sealed system so if you had to recharge it there is a leak somewhere. The leaks can sometimes be a pia to find. I would also visually check the condenser in front of the radiator to see if you can see a sign of a leak such as dampness.
Gary
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
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From: Minneapolis Mn
Good info, thanks much, gives me something to start on. If I don't have a chance to get to it tonight, it will have to wait till next week but beings it's so cold out, I don't think that's going to be a problem. 
Instructor
Joined: Dec 2012
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From: Ball Ground Georgia
With the temps that cold, the A/C probably won't engage the clutch. You can jumper the pressure switch mentioned above to do a quick test of the clutch, but it may need to be above 40 degrees or so to get it to work "normally".......
Thread Starter
Safety Car
Joined: Aug 2013
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From: Minneapolis Mn
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
Likes: 605
From: Minneapolis Mn
Had a chance to do some checking and made progress.
First tried running the defroster, control to cold and fan on high - nothing.
AC on max, fan on high, temp to coldest setting - nothing
Pulled the connector off the a/c clutch coil - no current there.
Next was pulled the connector off the 'pressure cycling switch' and jumpered that, clutch now engaged fine.
I assume that means it's likely the Freon has leaked out. Having had it just recharged last August (R134A) so I'm assuming it's leaked out by now. I'm guessing I'll have to get it charged up some before I can track down where it's leaking from but that's for another day when it's warmer. I'll have to check out instructions on what and how to do it (new experience for me).
One question though. Looking at the schematic there's a fuse shown by the blower motor that I'm not finding on mine. I find nothing there, no indication there ever was or could have been removed. Is the manual wrong or am I missing something? I'm attached the shot from the fsm I'm looking at relating to that fuse.
First tried running the defroster, control to cold and fan on high - nothing.
AC on max, fan on high, temp to coldest setting - nothing
Pulled the connector off the a/c clutch coil - no current there.
Next was pulled the connector off the 'pressure cycling switch' and jumpered that, clutch now engaged fine.
I assume that means it's likely the Freon has leaked out. Having had it just recharged last August (R134A) so I'm assuming it's leaked out by now. I'm guessing I'll have to get it charged up some before I can track down where it's leaking from but that's for another day when it's warmer. I'll have to check out instructions on what and how to do it (new experience for me).
One question though. Looking at the schematic there's a fuse shown by the blower motor that I'm not finding on mine. I find nothing there, no indication there ever was or could have been removed. Is the manual wrong or am I missing something? I'm attached the shot from the fsm I'm looking at relating to that fuse.
Team Owner
Joined: Sep 2003
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One question though. Looking at the schematic there's a fuse shown by the blower motor that I'm not finding on mine. I find nothing there, no indication there ever was or could have been removed. Is the manual wrong or am I missing something? I'm attached the shot from the fsm I'm looking at relating to that fuse.
You need to see wiring for whichever you have for specific components used, components and locations are generally on the page following the appropriate wiring cell.
Last edited by WVZR-1; Feb 2, 2016 at 06:17 AM.
Thread Starter
Safety Car
Joined: Aug 2013
Posts: 4,429
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From: Minneapolis Mn
The reason I asked about the fuse was I once had a 74 Malibu that had a fuse by the compressor though it was a different style compressor. Every year it popped the fuse the first time you engaged the a/c for the cooling season though this is the first time I tried it during the winter months. Just checking if there's supposed to be a fuse on this one also in case I have the same issues. Last summer was the first time I tried the a/c out in the 2 years I'd owned the Vette.
I appreciate everyone's help, I've made headway on this. At least I know the clutch is good now and it's noiseless compared to the old squeaky one.
I appreciate everyone's help, I've made headway on this. At least I know the clutch is good now and it's noiseless compared to the old squeaky one.