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Stupid Question of the day (A/C recharge)

1943 Views 10 Replies 8 Participants Last post by  96Fleetwood
Hey All,

I have a 76 Fleetwood - runs and looks beautiful, but the AC doesn't blow cold. Now that it's getting warm it's time to give the matter some attention.

I've never dabbled with AC systems before & know nothing about it. What kind of refrigerant can I use to recharge the system? Not sure what I can use - do I have to worry about compatibillity with a system that's 30 years old?

Any suggestions would be highly appreciated.

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ive wondered the same thing. i have an 85 and well... the ac works its just not blowing as cold as it should be.
I have a 1976 also. Coupe DeVille. My system uses r-12 (freon) which has leaked out, and I am trying my best to restore the a.c to its original working condition. Problem is once the r-12 has leaked out..the system has a safety "switch" that blows, causes the compressor to stop working until the r-12 is put back in, wherein you then have to replace that "switch." If the system has been empty for a while, it does need can still find mechanics that will service and KEEP the r-12, but it is COSTLY...

Some garages will have you convert to hc-134a (the current refrigerant) that is not harmful to the environment like r-12. Hc-134a is cheaper and used everywhere,,,,Problem is I hear once you do convert, the compressor ends up failing...:thehand:

Be careful. I SHOW my car and keep it as original as I can afford. I would NEVER use 134a in place of the r-12. The system was originally designed for pressures on the r-12 only!
Problem with R134a in a older R12 car, is the molecules are smaller than R12, and the R134a cars have a nitrl barrier hoses. The later R12 cars got these hoses, but older cars like the 76 will not. The system will always been leaky and need to be recharged more often than with R12.

So, a R134a retrofit (or anything similar) would work, but won't legally be 100% correct if you don't put on the adapter fittings and add the appropriate retrofit stickers.
Not only that any RC-134 conversion will not cool as effectively as an original R-12 setup. Newer cars (1992 & up in most cases) used much larger condensers to provide better cooling. You won't be as comfortable in a R-12 to R-134 conversion, although the Climate control will will probably keep up in all but the warmest weather - like we have 8 months out of the year here in FL :stirpot:

Also you CAN'T buy R-12 anywhere, buty you can but little recharge cans of R-134 :bouncy:
Is the compressor clutch engaging when you set the a/c to cool?
I've had fantastic luck with a product called Freeze12, which mixes with your existing charge of R12 and is compatible with any ester, mineral, or PAG oil.

Freeze12 also blows colder than R12 for whatever reason, so less of it is needed when recharging. Its made mostly of R134 and propane, completely safe and no more flammable/dangerous than R12.

I'm not a dealer, just a very satisfied customer. :) Pick it up on eBay or a local auto parts store for $9-$12.
Do NOT MIX R134a and R12!!!!!! That is a sure fire way to lunch a compressor and hose up your entire system!!!!!!
Thanks for all the responces!

I did get it recharged, but something isn't working. The compressor starts up like it should, and the pressure is holding. However, it's still blowing warm air.

Not sure what the problem is - but will have to bring it back to the shop for a more in - depth look.

Anyone else have a problem like this?
You had the system checked for leaks? What type of freon did you recharge with?

My father and I converted his 1970 Electra 225 Conv't to R134 and we have to recharge it every year. Still cheaper than R12.
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