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A-6 Compressor Question

SSuperDave

SSuperDave

Badass 5.0 Owner
Senior Member
I got the new electric fans set up on my '68 Caprice, and boy, do they work well! I started to go to the cruise tonight and a block from home, the a/c compressor reeif valve popped off and vented out all the refrigerant. I did not realize that the fans were not on yet, and with no air flow across teh condenser, the head pressure rose to the point where it popped off. I am going to wire one of the fans to come on when the compressor engages, and leave the 2nd one on the temp switch, which shoudl resolve that issue.
My question is, will the pressure valve reset itself, or does it have to be replaced once its popped off? I've never had this happen, so I don't have any past experience to fall back on. Also, do you think my assessment of why it happened is correct?
Thanks
 
I need to dig out my factory service menu.

What I can tell you is I looked at 3 compressors, my OEM restored and "spare" units have this long valve, my other Chevelle has had several compressor replacements and has a small valve. IIRC they may reset but I will verify (when I find the manual).

1720234337362.png
 
Dave,

All the Overhaul manual states is:

1720266356550.png

I am going to assume it resets itself, did the SuperHeat switch melt the Thermal Fuse?
 
I do not see any other switches on the back of this one, but am familiar with them from R-4 compressors. I know reman units have a plug in them held in by a snap ring that you can remove to install a switch if needed. I may pull a vacuum on it today and see if it holds, I take it to work to charge using the a/c machine to get the exact amount of refrigerant into it.
Thanks for the effort, it never ocurred to me to check the manual...
 
SSuperDave said:
I do not see any other switches on the back of this one, but am familiar with them from R-4 compressors. I know reman units have a plug in them held in by a snap ring that you can remove to install a switch if needed. I may pull a vacuum on it today and see if it holds, I take it to work to charge using the a/c machine to get the exact amount of refrigerant into it.
Thanks for the effort, it never ocurred to me to check the manual...
Click to expand...
My pleasure! All of mine are from 72s, your year may be different.
 
Someone on ChevyTalk said it resets, so I'm good to go. The relays yhat I bought for the fan had a green wire, the directions said if you connected it to the compressor power wire, when you turned on the a/c, the fan would engage. WELL THEY FUCKING DON'T!! I ran a separate relay from The copmpressor to one fan that comes on with the a/c so this will not happen again. The other fan still turns on and off with the temp sensor, and with the a/c off, the both turn on and off with the temp sensor.
What has upset me, is that I buy all this stuff that is supposed to be plug and play because I'm an electrical idiot, and am willing to pay for it to be easy, but its always the wiring diagramthat somebody drew on a napkin with a crayon that gets the job done...
 
I run two electric fans. One on the engine side that is a puller. its on a switch in the car. I turn it on when I leave the house and it stays on until I shut off the car. I ALSO have an fan that's on the front of the condenser and is a pusher that's wired to the AC clutch switch. It comes on when the AC comes on. The Chevelle in the heaviest of summer heat never goes above 170/175* with both fans on.

My engine builder (VORTECPRO) installed a 160 high flow thermostat and said to put a fan on it at all times. Engines run cooler if cooled from the start. Not trying to cool AFTER they are already heat soaked.

My AC guy said to install the pusher on the condenser to keep head pressures low and cool.

The car runs cool at 600hp in idle Florida traffic and the AC will freeze you out even on low. The worst part is having to turn the AC off because it gets too cold.

I run a Powermaster 150amp 12si alternator
 
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Both of these are pullers, one is wired to come on with the AC compressor, which is pretty much always down here, the other one comes on from a temp sensor. So far they are working very well to resolve my issue. It charges right at 12 volts in gear with both fans running so I'm thinking I have enough alternator. Once you start moving the voltage goes up.
 
If it's at 12v at idle it's not enough. at idle with everything on it should still be charging at about 13v.
 
Try this out.... put your headlights on with the fans running and if they are dim until you accelerate the engine, you're drawing on battery alone so it's not making enough power.
 
kmakar said:
Try this out.... put your headlights on with the fans running and if they are dim until you accelerate the engine, you're drawing on battery alone so it's not making enough power.
Click to expand...
Could his alternator-to-battery wire be too small a gauge ? Doesn't it need to be 6 or 8 gauge wire ?
My harness is calling for 6 gauge.
 
So I just run a 6 ga wire from the post on the alternator to the battery with no other changes?
 
Beth said 6 ga from alt to batt, you said 4-6 ga, if its not alt to batt, where do you add the wire?
 
Alt to battery is correct. If the alt isn't putting out enough amps at idle (should be charging at around 13v even at idle), then you'll have to get a bigger alt and replace the #6 with a #4.
 
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