[Carmine]

Hi everyone. I recently installed a stock ac compressor in my factory ac '71 GTO. It's bolted in but I don't have it completely hooked up yet. It suppose to work. The wiring harness for the compressor was lying on the manifold and I checked if with a test light. Current to it when I move the ac lever on the heat/ac panel in the car. I put the harness on the compressor and tried the lever but nothing happened. I don't have a fan belt on it either. Would anyone know if the compressor should turn with the above procedure, or does it have to be engaged mechanically first. It does turn freely. Not frozen. Thank you, Carmine.

[tigergto]

I'm thinking you need the belt on it.

[johnta1]

What are you trying to determine?
If the clutch works?

[Shiny]

Your question suggests you may be expecting the electrical power to cause the compressor to spin. If that's the case, there is no electric motor in the compressor. The rotating power comes from the belt, and the electrical connection actuates an internal clutch. Others can comment if it is possible to verify the clutch works or not by applying current without it spinning. I don't have a clue about that. It might make noise, but I doubt you would see anything move on the outside.

[West Coast GTO]

I believe the clutch engages when the A/C signal ( 12 volts) tells the clutch to engage. Some systems have a minimum pressure before clutch engages and some don't. 12 volts to the clutch should allow you to hear the clutch switch to engage.

[BertMac]

The clutch isn't going to engage if the system isn't charged. Put a jumper on the low pressure switch if all you want to do is ck the electrical, then the clutch should pull in when you turn it on in the car. It doesn't need a belt for the clutch to pull in.

[pont3]

Originally Posted by BertMac

The clutch isn't going to engage if the system isn't charged. Put a jumper on the low pressure switch if all you want to do is ck the electrical, then the clutch should pull in when you turn it on in the car. It doesn't need a belt for the clutch to pull in.

I think this is true only for later systems. My '71 clutch will engage with the system totally devoid of any charge. If I remember correctly, the system changed in 1973, thus requiring the system to have some charge before the compressor clutch would engage. But even those systems could be "tricked" (by using a jumper) to allow the clutch to engage regardless of Freon charge.

[Carmine]

Great responses as usual. Yes, I just wanted to see if the clutch would spin. Thank you everyone, Carmine.

[Carmine]

I'm still in the process of hooking up the compressor. In the area of the compressor, I came across wires that I don't have a clue as to where they go. The wires are black and black with a thin yellow stripe. They are in a small round cap and are male ends. I don't know where they originate from, but I believe they have something to do with the ac/heat. I looked at my wiring schematic and couldn't find them. I'm going to post a pic. Please take a look and see if you can identify them and/or where they go. Might not be the best pics.

Also, what I could really use, would be several good pics of a stock ac unit in a '71 GTO. I've looked in my repair/assembly manuals, on Youtube, and nothing gives me close-up's or the complete pic. I know I am still missing parts, but don't know what they look like or are called. I even went to a big car show/swap meet today hoping to find some examples, but nothing. Many GTO's, but none with ac. So, if anyone could post some pics, I'd really appreciate it. Thank you, Carmine.

[West Coast GTO]

Carmine:
Are you SURE that one wire is black with a yellow stripe OR is it black with an orange stripe?
I ask because it looks like the automatic trans kick down solenoid connector and that tracer wire is black with orange. If you have a continuity tester, go back to your gas pedal and connect one end to the engaged lead( hot with 12 volt power when kick down switch engaged) when switch operates and connect the other end to the black with orange( yellow) stripe. Also, in the assembly manual under the electrical schematic, it should show the black with orange tracer.

Originally Posted by Carmine

I'm still in the process of hooking up the compressor. In the area of the compressor, I came across wires that I don't have a clue as to where they go. The wires are black and black with a thin yellow stripe. They are in a small round cap and are male ends. I don't know where they originate from, but I believe they have something to do with the ac/heat. I looked at my wiring schematic and couldn't find them. I'm going to post a pic. Please take a look and see if you can identify them and/or where they go. Might not be the best pics.

Also, what I could really use, would be several good pics of a stock ac unit in a '71 GTO. I've looked in my repair/assembly manuals, on Youtube, and nothing gives me close-up's or the complete pic. I know I am still missing parts, but don't know what they look like or are called. I even went to a big car show/swap meet today hoping to find some examples, but nothing. Many GTO's, but none with ac. So, if anyone could post some pics, I'd really appreciate it. Thank you, Carmine.
Attachment 453475

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[Carmine]

Originally Posted by West Coast GTO

Carmine:
Are you SURE that one wire is black with a yellow stripe OR is it black with an orange stripe?
I ask because it looks like the automatic trans kick down solenoid connector and that tracer wire is black with orange. If you have a continuity tester, go back to your gas pedal and connect one end to the engaged lead( hot with 12 volt power when kick down switch engaged) when switch operates and connect the other end to the black with orange( yellow) stripe. Also, in the assembly manual under the electrical schematic, it should show the black with orange tracer.

I'll check it again, but I do think the stripe is yellow. It's part of a taped harness that comes from the rear of the motor, up the passenger side. The wires aren't very long and can't go too far. In one of the pics in my assembly manual, it shows a caped wire that connects to some part of the ac/heat box, but mine doesn't have that female end anyplace. It's not the greatest diagram. If we're talking about the solenoid kick down inside the transmission, I have that working properly. It had been lacking the wire from the pedal switch to the solenoid. I forget the 2 colors, but I can look again. What I did was, identified the switched 12v prong on the pedal switch and the other wire had to go to the transmission. I could never locate where it went once it left the switch. To save myself some grief, I ran a new wire from that prong to the transmission. I had someone press the gas pedal while I was under the car and I could hear the solenoid in the transmission reacting. I do believe I have that correct, but I will check the kick down switch as you suggested. Thank you, Carmine.