2 months ago topped up my 87 monte carlo (that the air hasn't worked for 7 yaers) and a 67 Skylark with a propane based equivilant Duracool brand refrigerant. I bought the adapter and filled them up. On the monte it works great. On the 67 it works but the compressor makes loud valve noises. Is all I have to do is discharge the system, get a new compressor and recharge it with the same stuff. I know there are laws for discharging. Ray
Duracool is HC-12a. Propane based. Go turn on your gas grill and don't light it. Same thing. I don't see the difference. Just don't try that with 134.......that stuff is regulated as an ozone depleting gas and should not be discharged into the atmosphere. Glad to hear that one other person besides myself likes Duracool. Are you sure your system isn't overcharged? That will cause compressor noise and may have already ruined yours. If you added refrigerant until the bubbles in the sight glass disappeared, it's very likely that you overcharged it.
No it ain't overcharged. I bought the gauge and adapter. The cans only put out so much pressure. Once the A/C system absorbs so much that's it. It pretty much idiot proof. The system will get to a where the pressure is the same as the can. I think that is why they sell the adapter without the gauge. Ray
uzzled: No way. I don't know who told you that, but if you did it that way then you are DEFINITELY overcharged. ou: If you put in more than about 4-1/2 cans then you are overcharged. The best way to add refrigerant is to figure out exactly how much to add by weight. And then fire her up, and dunk the can in hot water to make the pressure rise so it will go in the low side faster. When the can feels warm on the bottom then it's empty. You can keep adding refrigerant until the cows come home, at least until the compressor locks up b/c liquid refrigerant is not compressible like hot gas is after it leaves the condenser. To the best of my knowledge, when a system is overcharged, there is so much refrigerant in there it leaves the condenser as liquid and as it hits the compressor.........bam! :shock: Often times when that happens, if you are lucky, the clutch will slip and start smoking before something breaks but not always. Incidently, Duracool is very light by weight and about 4 lbs. of R-12 is the same as about 1 lb. and 7 ozs. of Duracool. I'd start by removing some from your system and watch your high side, maybe try bringing it down a little and see if the noise goes away before forking out $$$$ for a new compressor.
The 67's compressor makes a horrible tapping noise. I think the reason why is it never had a belt on it for a long time. Even in the winter if you you have a car on defrost on it will run the A/C system and defog the windows. The valves in the compressor got rusted. I think that is why they tap. Ray
if your compressor is noisy and you're not dumping liquid refrigerant into it(suction line frosted), it's probably history. Overcharging will bring high side pressures and temps up and overload the compressor til the belt can't turn it and of course you won't have any cooling and it will make a little more noise than usual but not like what you're describing. It could possibly be low or out of oil but most likely the damage is done. I think it's time to start over and buy a new compressor.
I got the gauge to read 36-37 psi. The compressor works but the tapping noise is not good. Looks like I need a new compressor. Thanks for all the help. Ray
It's really hard to diagnose these things over the internet, but high low side pressure is a classic symptom of overcharge that will cause compressor noise. After installing your new unit, just be careful not to add too much refrigerant and follow the instructions regarding the oil carefully. Good luck, I hope my advice has helped you.
I too have switched to Duracool Refrigerant. It really works very well. The A/C in my 66 Riv is very nice and cold. Very Satisfied.:beer
