73 AC mystery component
Thread Starter
Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
73 AC mystery component
This photo shows a wiring component on my 73 L82 with Air Conditioning. I can't find it on my wiring diagram. It looks like it is missing a wire. Any suggestions on what it is and what it should be connected to would be greatly appreciated.
Unk
Unk
Racer
Joined: Sep 2009
Posts: 437
Likes: 3
From: Alvin Texas
It looks like a thermal limiter switch connector. one wire goes to the superheat switch in the back of the compressor, one wire is the feed source for the compressor the third wire goes to the compressor clutch.
The pic looks like the limiter is gone and a jumper is in it's place, a common practice to eliminate the thermal limiter which could be a PITA when the system was allowing a low pressure through the POA valve, the superheat switch would close and heat the fuse element in the limiter opening the circuit to the compressor clutch. It was often located on the suction line to cool the heater, that didn't work well either.
Yours looks like the clutch feed wire (green) has been routed to the clutch, bypassing the limiter.
The pic looks like the limiter is gone and a jumper is in it's place, a common practice to eliminate the thermal limiter which could be a PITA when the system was allowing a low pressure through the POA valve, the superheat switch would close and heat the fuse element in the limiter opening the circuit to the compressor clutch. It was often located on the suction line to cool the heater, that didn't work well either.
Yours looks like the clutch feed wire (green) has been routed to the clutch, bypassing the limiter.
Last edited by bpassmore; Jul 13, 2012 at 06:51 PM.
Thread Starter
Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
Many thanks for the information. That explains the splice in the green wire that is not shown. The black comes from the back of the compressor to this switch connector. The clutch is getting power but is presently unplugged. When I put the car back together I put in a new dryer and POA valve and had both the evaporator and condenser pressure tested plus put in new seals. Sorting this out was a job I had put off. Sounds like this is something that was a good idea to protect the system, but may have issues. I will look for a replacement but in the meantime pull a vaccum on it and charge the system. Thanks again, I owe you one!
Unk
Unk
Last edited by RU7376vettes; Jul 14, 2012 at 04:59 AM.
Safety Car
Joined: Aug 2001
Posts: 3,683
Likes: 202
From: Waterford Mi
You are missing the cover. There are suppose to be three wires. The two outside wires are what allows the voltage to get to the clutch. The center wire is suppose to hook up to a switch on the back of the compressor. It is a fuse that blows if you loose your charge. Most just disconnect them because GM had an issue with them blowing quite a bit even when they did not have a leak. Most of the compressors do not have the switch in them any more. I came across a bunch of the fuses at a flea market years ago.
I recently replaced my system with a new system that uses a orifice tube and in stead of the VIR valve anyways.
I recently replaced my system with a new system that uses a orifice tube and in stead of the VIR valve anyways.
Last edited by redwingvette; Jul 14, 2012 at 10:17 AM.
Thread Starter
Racer
Joined: Apr 2009
Posts: 330
Likes: 44
From: Cincinnati Ohio
Nice conversion Redwingvette! You have done a lot to your 73 as well. Noticed the steering and exhaust systems. I went with chambered exhaust and modified the rear pipes to fit the stock tips. Just put a 2.5" Magnaflow system with the X pipe on my 55, can't wait until finished with the new wiring to see how it sounds.
Thanks again,
Unk
Thanks again,
Unk
Burning Brakes
Joined: Sep 2005
Posts: 1,050
Likes: 205
From: Lewes Delaware
You are missing the cover. There are suppose to be three wires. The two outside wires are what allows the voltage to get to the clutch. The center wire is suppose to hook up to a switch on the back of the compressor. It is a fuse that blows if you loose your charge. Most just disconnect them because GM had an issue with them blowing quite a bit even when they did not have a leak. Most of the compressors do not have the switch in them any more. I came across a bunch of the fuses at a flea market years ago.
I recently replaced my system with a new system that uses a orifice tube and in stead of the VIR valve anyways.
I recently replaced my system with a new system that uses a orifice tube and in stead of the VIR valve anyways.
Here it is in my 73:
Fran
Race Director
Joined: Feb 2001
Posts: 11,250
Likes: 2,073
From: Grapevine Tx
2018 C3 of Year Finalist
2016 C3 of the Year Finalist
That whole little pigtail and fuse went bad on my 72 and short of having to buy a whole engine wiring bundle, I found just the connector on a John Deere tractor supply website. I looked all through my emails and I can't fine the company.
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