Convert my A/C

[77cutty]

Hello,

I been searchin all over and looking for a way to convert my ac in my 77 cutlass supreme to r134 or something. I remember seeing in here that a member converted to 134.I just want to know what exactly needs to be done and what parts are needed, any help would be appreciated on this subject.

-77cutty

[texxas8902]

People will tell you different but I have converted 15 or 20 cars myself and this is simple and worked for me. Make sure all the R12 is removed from the system. Check to make sure your compressor is still working and not locked up. You will need to purchase conversion fittings and 134. I would also get a can of 134 that has an ounce or 2 of stop leak and oil in it. Buy a decent fill hose with a gauge on it. Install the fittings and use teflon tape so they don't leak. Hook up the stop leak 134 can first on the low pressure side, start the car, set A/C to high and tap the can. This should kick the compressor on in a few seconds. It will cycle at first and then stay on as the system fills. Fill system to about 80% of R12 capacity using regular cans of 134 after using the stop leak can. If your car has a sight glass watch for it to clear of bubbles. This is NOT fool proof, if you don't have much mechanical ability you may fry the compressor or waste all the 134. I haven't had to change the compressor oil or flush systems that still had a little residual R12 pressure and were not opened to the atmosphere. It is best to do it on a really hot day, it seems to charge faster and I put a large fan in front of the car and mist the condensor with water once in awhile. When 134 first came out everyone said to change the O rings, the compressor oil, flush the system, all kinds of things. It was said that 134 was not a drop in replacement for R12. In my limited experience I would say that is not true. I buy my 134 at Walmart, $6.88 a can in my area last time I bought it and with the fittings and freon usually spend about $25 to change a car over. It worked on my 76 442 and my 67 Cutlass with nothing more than the fittings and 134.
This has worked for me many times but may not for you. Proceed with caution.

[sumrof75]

I worked in a repair shop my father owned off and on many years, the only thing I would add to Tex is to replace the orfice tube and reciever dryer for the best results.

[texxas8902]

I worked in a repair shop my father owned off and on many years, the only thing I would add to Tex is to replace the orfice tube and reciever dryer for the best results.

I would agree with that and do replace them ALWAYS on cars that I have to open the system on. Hell the GM orfice tube is only like $1.99 last time I bought one. But when I do the quickie change over on the cheap I don't mess with it. When I start replacing the parts and actually doing it "right" I take the whole system down and flush it with brake cleaner and change the oil out. It is ALOT more work and expense. I love it when the cheap fix works without a hitch.:D