A/C using R-12

[xxchief]

This is a general question on auto A/C units. My grand son has purchased a 87 Chev truck that has an A/C not working. It has a leak some where. When we put R-12 in it, it cools for a few days and looses the charge.

My question is, can I use the leak detector that is for R134 units to help us find his leak? I have not been able to find R12 leak detector

Once we find it, I will most likely change it over to a 134 system.

[MT-2500]

Originally Posted by xxchief

This is a general question on auto A/C units. My grand son has purchased a 87 Chev truck that has an A/C not working. It has a leak some where. When we put R-12 in it, it cools for a few days and looses the charge.

My question is, can I use the leak detector that is for R134 units to help us find his leak? I have not been able to find R12 leak detector

Once we find it, I will most likely change it over to a 134 system.

Some will work on both r-12 r-134a.
Give it a try on some r-12.
If not shot some r-134 a in it and leaqk test.
Also they make a leak dye and leak dyr kit that works good on hard to find leaks.
Good luck and.
Let us know how it goes.

[j cAT]

Originally Posted by xxchief

This is a general question on auto A/C units. My grand son has purchased a 87 Chev truck that has an A/C not working. It has a leak some where. When we put R-12 in it, it cools for a few days and looses the charge.

My question is, can I use the leak detector that is for R134 units to help us find his leak? I have not been able to find R12 leak detector

Once we find it, I will most likely change it over to a 134 system.

you may not be aware of this but R12 refrigerent is no longer used because it causes holes in the atmosphere...this R12 should not be used to find leaks...

the system should be leak tested with a 150psi nitrogen gas charge..using soapy water check for the leak ..usually the condenser connections O rings or a hole in the condenser coils..

the other area would be the compressor seals/shaft seal/or the compressor body itself...with the system pressurized at 150 psi see if it holds if not it still leaking, should hold for 24hrs ..


after you find the leak and it passes the leak test, then convert to R134..best to remove compressor and drain out the old refrigerent oil ..then add the conversion oil ...using a vacuum pump, pump the system down for a good 3-4 hrs then see if it hold vacuum for a few hrs ...if not you have a leak ...repeat the pressure test ..


If you have R12 refrigerent this would work much better than R134...this system not being designed for R134 does not work that good..., but its better than nothing ..