anyone done an a/c conversion

[riptide44]

just wondering if anyone has done an a/c conversion to r134a - i have a 92 jimmy 4.3 vin w and my r12 has finally run low - leak is fixed . but i cant get it recharged .

[pkasprzyk]

The main thing to do is to remove all the old oil. The 134a requires synthetic oil. You need to flush the system, replace expansion valve and accumilator. If you don't need a new compressor you need to remove all the old oil from it. You will also need to put new fittings on your high pressure and low pressure side. I bought a kit that came with rebuilt compressor, accumilator, expansion valve, flush and oil for around $250. Evacuate it before recharging. Took me about 5 hrs, but I am a shade tree mechanic. Be sure and replace your old o-rings and be careful with the flush. That is some wicked stuff!

[JustSayGo]

Search for an A/C kit that includes the items mentioned by pkasprzyk. Usually the hoses will be included. The reason that the oil is removed is because mineral oil will not absorb and flow with R134A like it does with R12. Rebuilders use this property to their advantage by adding enough mineral oil to their rebuilt compressor to coat the compressor parts and then draining any oil that will drip out. That small amount of mineral oil will stick to the compressor parts no mater what and will not mix with the R134A or the synthetic oil. Doing the same with a new compressor provides the same advantage.

Remove the old hoses and orifice tube and use the flush to wash out the evaporator and the condenser. Do not flush hoses with the alcohol cleaner. It bubbles like crazy with air pressure and you don't want any in your eye or even on your skin because of how it will remove moisture.

The kits are the most economical way to go. Often there are upgraded compressors that bolt directly in place. Change everything that can leak. All o-rings and hoses. You should find that the best supplier with the best prices and quality parts, also has instructions at their home page that should cover every detail.

Look at the tag on your car to see how many ounces of R12 are used in your system. When converting to R134A, the system is fully charged with 80% of what is listed for R12. Don't add the same amount or try to use a sight glass.

[riptide44]

great - thanks to both of you - i think thats what i will do and try to find a kit that replaces the hoses and etc - im guessing that 250 bucks was in american funds - we get " hosed " up here in canada - i think the compressor alone was about 350 - ouch - but the wreckers sell a/c components real cheap becuase they dont want to get involved with wether it works or not and if it leaks down the road etc. - if anyone knows if a 95 or newer compressor will fit please post back - i dont mind changing seals and all that in fact i would likely do that anyway if it came from a wrecker -