DBLBB32

I have an 87 C4. AC has never worked since I bought it 12 years ago. I guess it's time to get it working. I would like to convert it from R12 to R134A. Beside a New Compressor, what else do I need to purchase?

Joe C

you'll need a new accumulator(dryer). I just went through this on my 85. in addition to the new components (compressor, accumulator(dryer)), I bought a flush kit to clean and flush the evaporator, condenser, hoses, and high pressure tube. I did swap out the low pressure cycling switch and from the standard .072 orifice tube to a .067 assembly. you will also want to replace all O-rings, and get the 134a service adapters. I used ester oil in my system instead of PAG150. once I got my o-ring sizes sorted, everything went together without issues. pulled a system vacuum for about 4 hours, and added 36oz of R134a - high and low pressures within spec, and my center dash temp around 59° w/ outside temp of 92°. according to the chart, pressures and temps right on the money. a great source of info, literature, parts, and material is FJC. get a copy of the conversion manual - everything you need to know --



here's a link to their .pdf catalog -- http://www.fjcinc.com/wp-content/the...FJCcatalog.pdf

additional info -- http://www.aa1car.com/library/retrofit.htm -- http://aircondition.com/

Hooked on Vettes

Take the EPA open book test for $20.00 and get certified so you can purchase R12 legally. You see 12oz and 14 oz R12 cans on Craigslist all the time for $20.00. I believe your 87 takes 2.75 lbs of refrigerant.

https://www.epatest.com/609/openbook/

jose7740

I am working on my 84, replaced the compressor/accumulator/orifice tube, flushed the condenser and evaporator. The FSM says to add oil to the condenser and evaporator(about two ounces) Did you add any to your car? It also says to add oil to the accumulator. My components are from Four Seasons and they say to use Pag 150, how many ounces of oil you added to the compressor?

Joe C

I opted for ester over PAG since ester is somewhat universal for either R12 or R134a. either one is OK for the 134a conversion though. anyway, per instructions, added a total of 8oz to my system - 2oz each into the compressor, accumulator(dryer), evaporator, and condenser. IIRC, my 85 FSM says 6oz total (that would be for R12). from what I read, in a R134a conversion (PAG or ester), the total amount needs to bumped up to 8oz.

ddahlgren

Mine went from blowing ice cold with R12 to sort of cooling with R134a and yes properly converted. I would get the correct gas and keep it simple and OEM

crowz

To convert from r12 to 134a you just need a $39 conversion kit and presto it will be working fine no matter what anyone else says.

But that answer may not help you if you have other problems. You need to find out WHY its not working. The conversion kit is all you need to solve the Freon change over but that doesn't stop leaks, bad compressor or whatever else.

My 1987 puts at 38 degrees pretty easy driving down the road with the outside temp in the 90's. It will hold in the 40's no problem at idle. I converted it to 134a using the kit method I mentioned.

Joe C

what do you mean, "sort of cooling?" what's your center duct temp (vs outside temp/humidity), and what's your high/low pressures? properly converted doesn't necessarily mean operating properly. you may have other issues. when you say, "properly converted," did you do the conversion yourself, or did someone else? I see everything from the Walmart, conversion in a can for $39.95 to the $200 shop specials, to proper, $800 conversions. while i'm no expert on automotive AC, I did do my conversion myself, and "by the book." I can say it wasn't cheap - new compressor, accumulator, cycling switch, orifice tubes, and a system flush. I probably dropped $500 in the conversion. I did have a R134a manifold/gauge/hose set, but I did have to buy a vacuum pump. all my pressures and temps are in-line for a 134a system. I can say, my 134a system cooling is about the same as, what I remember, my R12 system. in fact, the first evening I was out with my new conversion, my wife asked me to turn down the AC, because she was too cold .

as long as you have a supply of R12, and everything works properly, or you do all repairs yourself, you're OK. the problem lies if you have to take the car into a reputable shop for any repair. as long as it's not anything more than adding a small amount of R12 , you're OK. the average guy doesn't have the equipment or even a R12 manifold/gauge set to properly service their system at home. if you have a failed component, or major leak, most shops will do a conversion. most shops will not repair a failed R12 system. i'm not sure, but that may be some federal guideline. several things to remember - it's against the law to manufacture R12 in the United States, it's against the law to import R12 into the U.S. unless you can find NOS cans of R12 on craigslist, most everything supplied by shops, or sold over the counter, is "recycled" R12, and you will pay an arm and a leg for the stuff. BTW, that $20 open book test to buy the stuff legally is a joke, and you don't need it to buy off craigslist - only if you buy it at a parts supplier, like NAPA, and you won't get it for $20/can - try $40-$50. while most, and most on-line sites say, R12 is better and colder that 134a, I have yet to see any factual test data comparing the cooling efficiency of two identical cars. not to get into a pissing contest, but my results differ from yours. anyway, have a good one, and stay cool!

Joe C

for $39, those temp readings are amazing - I get nothing like that. my center duct temps are in the upper 50's with an outside air temp in the low 90's and high humidity. according to the charts, everything's normal. when you did your conversion, did you replace your accumulator(dryer), O-rings?

BTW, these are the charts I used -





FWIW, my low pressure was 41psi, high 217psi, center duct temp approx. 58-59°, ambient temp 91-92° with humidity above 40%. BTW, the amount of R134a added to my system was slightly less than the conversion factor - probably 90%-95%. didn't want to open a forth can for just a "little more...."

crowz

Didn't change anything. If a system is working right already I always just use the kit.

Of course if the system was open to air for any time at all I change the dryer. If the system had leaks to start with those have to be addressed with orings and what not. If the compressor had problems its still going to have problems after the change over with the kit.

Ive done way over a 100 of the conversions and never had any issues with them.

Joe C

interesting! I decided to convert mine since my compressor was getting ready to take a dump. I considered rebuilding it, but didn't have the proper tools and with the cost of parts, I opted for a new assembly. since the system was open for some length of time, and looking into the conversion, a new dryer was in order. at that point I decided to convert it to 134a but not knowing anything about automotive AC, I decided on the method I used. one thing I don't understand with your conversion is the compatibility of the oil between the different systems - ??? - that's why I decided to flush all components. anyway if you've done over a 100 conversions, without issues, something's working for you. with my luck, i'd try it, and everything would turn to "schitt"

BTW, got a link to the kit you used? (for future reference)

BTW2, if you've done over 100 conversions, you are not your average hobbyist. do you work in some sort of automotive shop?

crowz

I never hunt for a particular kit. I just grab whats on the shelf at autozone, napa or wherever Im at.

I think igloo made most of the kits I used. The purpose of the "kit" is to convert the oil over. Otherwise you would just put 134a in. That's the whole reason for the kit is to handle the oil issue.

Also yes maaaaaanny years ago I was a mechanic. I do the conversions now for friends and their friends so I still do a few a year now. Also I have owned over 200 vehicles in my lifetime, car junky

EVERYTHING I own has a/c and it works. Cant live without a/c.

Joe C

not sure I understand - do you have to purge the old oil from the system, or does the kit make everything compatible? from what I understand, you need to get 95% of the old stuff out before using PAG or ester oil - ???

i'll have to check into the igloo kits.

I doubt i'd own 200 cars in 10 lifetimes - I never had AC in a car until 1985 - new buick century.

crowz

The kit has a special oil charge that converts the current r12 oil over to being compatible with the 134a. So nothing has to be drained. Just add the kit and enjoy cold air as long as nothings broke to start with.