DinoBob

My Father's 86 has not had a charge in the AC for quite some time. I'd like to convert to R134a and get it working. He just sprung for manifold gauges and a vac pump. Please share your own experience and tips for converting. Many thanks.

Cliff Harris

You should replace the accumulator. It has desiccant in it to keep the system dry. If you get moisture in the system it will become acidic and eat up the evaporator and condenser.

Also the old hoses are not barrier type hoses and the smaller R-134a molecules will leak out through the rubber.

You should use ester oil because it's more compatible with the mineral oil in R-12 systems. If you really want to do it right you should flush the refrigerant lines and use PAG oil.

You should pull out the orifice tube and check to make sure it isn't plugged up.

colter

Also need to change all of the orings, and probably go ahead and put new orings/seals in the compressor.

I've seen recommended to use a blue Ford orifice tube when changer over to R134.

Also when you get adapter fittings. Best to get the adapters that contain a new valve inside. I believe you can get these off of ebay and other places. They'll be brass.

Dt86

I wish someone would do a step by step thread on this. These always seem to to end up being "do this and that" threads.

ThomasRetUSN

I changed my 86 last year from R12 to R134. The only thing I did was vacuum it down at around 15 lbs for about 30 min. Then charges it with R134. I did not change one thing on the A/C unit. It blows real cold. I am very happy with it. Everyone thinks you have to change parts. Not true.

smile5

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I will have to agree. This is what I done to my 85 back in 2009 and it still works like a charm.

Cliff Harris

Corvettes were switched to R-134a from the factory in 1994. They used the same orifice tube part number for all C4s.

I've seen various reviews of the variable orifice tubes. Some people love them. Some people hate them. I have heard that they stick, but maybe the technology has gotten better recently.

whalepirot

My A/C shop just charged mine with R12, as that is what it was designed and optimized for. Works well, now; like new. My condenser leaked, after changing other o-rings and replacing the compressor, exp, valve and dryer.

R134a is reportedly compatible with either refrigerant and is rather inexpensive.