i was at the parts house the other day looking for one of those adapters that clamp on to the top of the small 12oz. recharge cans. of course they didn't have one and the guy said you can't even buy them anymore!?!?! new to me. i have about 7-8 of the 12oz. R12 freon cans and need to recharge the jeep. the guy said the new conversion kits work great. i asked about having to pull the compressor to drain the oil and he said it's totally unnecessary now that the oils are compatible. so what's the story behind converting a system now from R12 to R134A? is what that parts house guy said true? he also said the small cans are going for about $30 each and i should sell them, convert the system, and still profit.

4/5/2010 8:23:27 PM

talk to the man at four brothers on gresham lake- the can isnt the same diameter as the 134 cans is it? they make hoses that have a clamp that penetrates the side of the can instead of the top.

4/5/2010 9:49:13 PM

cool, man. thanks. i believe the top is larger than a 134 can.

[Edited on April 5, 2010 at 9:57 PM. Reason : -]

4/5/2010 9:57:21 PM

Quote :

"they make hoses that have a clamp that penetrates the side of the can instead of the top."

used one of those last time i had to recharge an R12 system. worked well.

4/5/2010 10:15:54 PM

I've got a can tap somewhere...sized for both R12 (small can) and R134 (large can) with both ACME and standard thread connections. It needs a new seal on it though.

There is no drop-in retrofit that works as well as draining the system, flushing all the old oil out, replacing the receiver/dryer, and putting the correct shit in.

I did an '89 Celica some years ago where I put in a new receiver/dryer and swapped out the compressor for a junkyard one from a '95 Celica...and flushed the whole system prior. It works better than every retrofit I've done, hands down. I used the correct weight and amount of PAG oil in the system.

HFC134 systems use a parallel-flow condenser with a higher efficiency than the series-flow ones found on most R12 systems. The compressor seal is made with different materials as well, and most R12 retrofits shit the bed because the compressor seal shits the bed and then you can't keep refrigerant in it.

The SuperDodge had been retrofitted, and was a horrible mess when I took some of it apart. Lines and compressor full of brown muck. PAG and ester oils are very hygroscopic...meaning they soak up water. And I don't care what they say, even with the new additives, PAG and mineral oil do NOT mix at all.

4/6/2010 9:06:23 AM

the SuperDodge makes BAD noises if you try to turn on the AC

4/6/2010 9:08:35 AM

The bad thing about drop-in retrofits is that you end up with way more oil than you need in the system. The key to a system's optimal efficiency is to maintain the oil level adequately enough to ensure lubrication of the compressor (and the thermal expansion valve if you have one; most newer American cars don't have one), but not so much oil that it interferes with the refrigerant's heat transfer and phase change. Ideally, a phase change refrigerant system would function best with NO oil in it...but you gotta keep the compressor lubed. It's best to follow the manufacturer's recommendations as to oil amount and type.

4/6/2010 11:03:07 AM

well, cool. thanks, dan. i guess i'll be stopping by four brothers to get an adapter made so i can keep R12 in it and hopefully it'll hold out for another 400K.

4/7/2010 8:59:59 PM