ChazBluJay

Just purchased a 1987 Vette and would to what is involved in the
R12 conversion and cost?

MotorCity_87_C4

I'm getting ready to do this in my 87. I bought the R134 compressor and conversion kit and new condenser (old one is beat up from rocks and stuff). About $450 in parts.
Expect an AC shop to want to charge over $1000 to do the conversion. I had my R12 freon removed and after I change the parts (there's instructions in the kit) I have a vacuum pump and gauges to draw a vacuum and recharge with R134.

Depending on how bad the leak is you may want to spring for a R12 recharge each spring. Mine leaked like a sieve and held a charge for about 2 weeks....

zr1fred

They sell the kits at the parts stores, its pretty straight forward. You don't need to change any parts or flush the system. All the C4's were pretty much designed to go with 134 anyway. You will probably have some very slow leakage due to the age of your lines, but that should be minor. I've switch cars over for years with no problems.

Railroadman

We were on vacation in 2009 when we had to have ours done and wound up at a dealer. They changed a couple fittings and re-charged it with the new stuff, total cost was under $250. It was July, we had 2 more weeks left on the trip, and it was worth every penny! If you have to have a new pump or whatever, naturally it will be more. Good luck with it.

Muffin

zr1fred is spot on about changing major parts. I do suggest the system be flushed and a new expansion valve installed. New drier is always a must.

SunCr

The C4, through '93, was designed to run on R12 and though '90 began to adopt some changes in anticipation of R134, these cars lack a key element; that is the ability to cool the charge properly at idle and low speeds when the outside air temp gets 90 or above. The R134 molecule is smaller and can build incredible pressure when the outside air temp gets up there and starting in '94, the Engineers designed the cooling fans to crank on below 200 psi which keeps the charge at a reasonable level. Your R12 Vettes doesn't turn anything on until 230 psi. Through at least the '89, there is nothing you can do because the ECM relies on a pressure sensitive switch as the ECM signal and there aren't any switches available with a lower threshold. The accepted solution is to use less R134 than the R12 fill - maybe 75 to 80% of the capacity shown on the Blower Motor Housing. Beginning with the LT Motors, the system uses a Pressure Sensor which returns voltage proportional to pressure. For those systems, you could reprogram the PCM so that the Main Fan is on with a signal of 175 psi. That's not always an easy task. To me, it's easier to just get an online license and buy all the R12 you want - no-one (other than enthusiasts) wants it anyway and most 20 year old systems need so much more than gas, it'll still be the cheapest part of any rebuild. For any work, a new Accumulator is a must; leak checking to keep whatever you dump in it a no brainer, and stay away from any miracles in a can especially hydrocarbon products which could ignite - especially if it's got a leaky evaporator and someone lights up (and you don't want to breathe any of this stuff anyway).

dallas916

The R-12 in the system is NOT compatible with the R134 at all. Don't mix them. At the very least a flush is needed, then of course, the fittings need to be changed. And, FYI they have just changed the R-134 formulation, which is now almost twice as expensive as before. The Europeans never liked the R-134 due to its toxicity and have tried for years to get rid of it.

However, if you want to avoid all that expense and alteration of the original equipment use one of the alternatives. I have been using the products from Enviro-Safe for about 20 years...in at least 12 different vehicles...with absolutely no issues. Their formulation is 100% environmentally safe and is a lighter gas so it is much easier on the compressor. They have a specific R-12 replacement that can be aded to either R-12 or R-134 if necessary.

Contrary to all the DuPont propaganda put out it is just as safe as freon, if not more. You don't actually need to flush the system, but if you can't do it yourself there are not many licensed shops who will take out the DuPont crap and put in the ES....mostly due to our government's constant relationship with DuPont and other lobbyists in the refrigerant market who threaten the shops. BUT...there are some who do the replacement and have great success with it. The issue is more of not contaminating the very toxic R-134 or the (allegedly) ozone depleting R-12 with other refrigerants.

If your R-12 has already leaked out you just need to fix the leak and refill it with the ES. If you are worried you'll pollute the sky with the last few ounces of R-12 being used I suppose you could take it to a shop and have it sucked out. Yeah, right.

If you open the system you'll need a vacuum pump to get all the moisture and impurities out, then replace the drier and O-tube or expansion valve. But if you don't have a leak...or don't know where the leak is...you can put the ES directly in and crank it up to proper pressures. It's easy with a guage set. The ES also has a leak detector just like all the others.

Anyway, for more info just go on their website (www.es-refrigerants.com) or call them at 888-913-1110.

I DO NOT WORK FOR THEM OR SELL FOR THEM. I AM JUST A MULTI CORVETTE OWNER AND GEARHEAD WHO DOESN'T LIKE BEING RIPPED BY DUPONT EVERY TIME THEY CHANGE THEIR PRODUCTS.

Check it out.

Cruisinfanatic

They are?
134 didn't exist, or at least was not used when all except for the last couple yrs were built

Old87owner

I had mine retrofitted last year to r 134. If I remember correctly, I spent about 300 on it. The shop had to replace a hose or two. Otherwise it should only cost about 200.

But, r 134 doesnt cool quite as well as r 12. But it isnt too bad though.

zr1fred

I realize that, but they have the larger ducting required for the lower efficiency 134. (as opposed to most of the 70s and earlier cars.) While technically valid, most of the stated differences in the refrigerents come down to a simple fact. Millions of people are doing quite well with the conversions, they work, and they are easily (and quickly) obtainable.

Loby 1

I had my '93 converted to 134 last year. It cost about $250.

Works great no regrets.

JackDidley

I put one of those $40 kits in my 87 and it works fine. May not last though, it was only 8 years ago.

Cruisinfanatic

I did the same. R12 leaked since the vette was 5 years old. Picked up the kit at Walmart about 5 years ago and I've had AC ever since. Never had to recharge.

Goldcylon

134 has never really impressed me on the newer cars. I swear the R12 works better. What about the freeze stuff as a replacement

ejscarfo

I have a Freeze-12 kit sitting in my garage that I was going to use on my 85. Anyone ever use that stuff?

eaglevision993

I converted my 88 with the proper oil and R134a.
Had the old R12 evacuated and pulled a vacuum for half an hour. The shop owner told my the most important thing is to add an oil to the system that circulates with the R134a and lube the system. That is the famous "compatibility".
He said if the system fails within a year because of the R134 he will repair it for free.
Needless to say, it still works fine.Total cost: about 70$
Any thoughts about the way I did it?I felt a little uneasy as this seemed a like a half asses job, but it still works find a year and a half later.

The shop owner told me that most of those "R12- compatible" refrigerants contain high numbers of R134 and the only difference is to add another refr. that transports the old mineral oil so you have to add an 134a oil. He showed me the percentages on a sheet and most "compatible" refrigerants contained well over 90% R134a.

I don´t remember if it was esther or PAG oil, but he told me the right one is important so it will mix with the old oil.

As I said, I was a little worried first. But he was right it seems....

eaglevision993

And I forgot:
That shop has a good reputation and I assumed he won´t ruin it for 70$.
Years ago I had my Lebaron (first car) converted the same way, the A/C worked when I sold it 4 years later.

JackDidley

It should be fine Ive done 4 cars with long term success. One I did in 2001.

c4sailor

My 87 ran about 8-900 installed (about 3 years ago) with all parts and conversion to 134. Compressor, orifice, evaporator, - I think that's all the parts - and labor. Compressor is a "Remanufactured for GM".

My compressor was shot at the time and I was told that typically when the compressor fails it craters the rest of the system because of the little pieces and parts it spews. So, better to do the whole thing than risk fouling the new compressor. And converted to 134 in the process. Sounded reasonable to me.

dallas916

R-134 systems use PAG oil...usually "100" or maybe "150". I'm not sure what the "46" is used for.