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Allison Specialist!
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675 Posts
Discussion Starter · #1 ·
Is there a relay that controls the power to the A/C clutch? if so were is it located? I see one that might possibly be it(above the brake booster) but not sure and i cant find a diagram to tell me what it controls...Its on a 4.3l v-6...
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Well telling us your model year would help...............

and

what symptoms you are having.............
 

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HOT AIR BALLOON OWNER
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94(the one in the sig)...Clutch isnt kicking on.....I jump it for a sec and it kick on....


System is probably low. Keeps itself from coming on for safety reasons..... lost refrigerant equals lost oil. No oil in the compressor is like your motor without oil... not good.

Could have bad pressure switch

I'd suspect relay last.
 

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Allison Specialist!
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675 Posts
Discussion Starter · #5 ·
Okay thanks!......Do you know how much the system holds? Im a take it somewere and have it checked since i dont have any gauges....
 

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HOT AIR BALLOON OWNER
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I've posted the capacities on here before, have to search.

Probably 2.5-4lbs of 134A. I do not think GM still used R12 in '94, but I am not sure. There were vehicles released in 1990 that came w/ 134A.

DO NOT use any stop leak, it's not good for the system.
 

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Your HID Preferred Vendor
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I would go ahead and take it in if you dont have any guages. theres not much your going to be able to do as far as diagnose. The AC system is pretty complicated for those of us who arent real familiar with it. I'm a mechanic, ASE certified in hvac, but we don't use it up here. AC is one of the most complicated, hard to remember systems, imo. and they are easy to destroy. we had an ac machine that the scale needed calibrated on, nobody told anybody, i charged an ac system, destroyed a brand new compressor because it overcharged the system. Low pressure will keep the ac from working, and on a 94 thats probably the direction i would go.
 

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Allison Specialist!
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675 Posts
Discussion Starter · #8 ·
I've posted the capacities on here before, have to search.

Probably 2.5-4lbs of 134A. I do not think GM still used R12 in '94, but I am not sure. There were vehicles released in 1990 that came w/ 134A.

DO NOT use any stop leak, it's not good for the system.

Yeah its134-a and i didnt plan on using that stop leak stuff just gone take it to a shop and see if its low or not and go from there.......info is greatly appreciated....
 

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HOT AIR BALLOON OWNER
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If it's basically empty, I'd go ahead and open the fuck up. 10 years is about all you can get out of one +/- 5 years on average before it requires major service.

Flush it out the old oil, go with Nylog o-rings, replace the dryer, replace expansion device (orifice tube on GM I recall), fill with oil, seal it up, vac down, then charge. etc

The gay R4 compressor likes to leak from the front seal, GM redesigned this (and the compressor to the stepped port design) so it is far less leak prone... but then you'll have to purchase a new compressor to counter this. You can yank the clutch and replace the o-ring, I would if your compressor is good and on a tight budget.

Remember to run the A/C at least once a week during the winter for a good while, not just five minutes. This keeps the oil circulating and the o-rings lubed.
 
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