I BOUGHT THIS CAR LAST YEAR KNOWING THAT THE A/C WAS NOT WORKING AND BELIEVED THAT IT WAS PROBABLY DUE TO A FAULTY COMPRESSOR. I'D LIKE TO CONFIRM THIS BEFORE REPLACING THE COMPRESSOR AND REFILLING WITH THE PRECIOUS R-12, BUT CAN'T TEST FOR LEAKS UNLESS THE SYSTEM HAS SOME CHARGE. CURRENTLY THERE IS NO FREON IN THE SYSTEM. I'D LIKE NOT TO USE R-12 FOR THE TEST! IS THERE SOME ALTERNATE THAT I CAN SAFELY USE FOR THE TEST THAT WILL NOT PREVENT ME FROM REFILLING WITH R-12 ONCE I FIND AND FIX THE LEAK(S)?

THANKS,

STEVE

hey sms, I have not tried this product, but from what I've heard, this is they way to test or top off your R-12 system. Good luck


http://www.freeze12.com/

PLease let me know if it works

Regards,

__________________
a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____

PLEASE DO NOT TOP OFF AN R12 SYSTEM WITH FREEZE12!!!!!!!!

There is a very valid reason for this. What happens is someone comes along and recovers the refrigerant from that system resulting in the contamination of whatever R12 is in their container.

The ONLY R12 we have left is what is on the shelves and what we can recover and recycle.

PLEASE DON'T CONTRIBUTE TO THE CONTAMINATION OF OUR REMAINING R12 SUPPLY!!!!!!!!!!!!!!!

A great way that shops look for leaks and is approved by the EPA is 2 oz. of R22 and then pressurize to a few hundred pounds with nitrogen. This is a great way because you have high pressure to find leaks, even on the low side with a sniffer.

Another approach would be a little R12 and UV dye with a UV light.

Please don't use Freeze 12, or even get it near an R12 system.

Have a great day,

Hydrocarbon refrigerants are very, very compatable with R12 systems. There are many hot discussions under what circumstances they are considered legal/illegal and and equal amounts of discussion over flammability issues. I'm not advocating it's use, just making you aware. I find a 60% propane/40% iso-butane mixture to be ideal for leak testing with UV dye and light in an R12 system. The refrigerant can be evacuated at the end of testing and used in the BBQ.

Duracool and Envirosafe are two brands that approximate the percentages I like (I mix my own). FWIW. no flames , please, as I'm not recommending it for use, just information.

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

I'm afraid you missed my point. He was talking about MIXING these refrigerants with R12 which risks CONTAMINATING OUR R12 supply.

Sure most anything is "compatible" with anything, but PLEASE don't contaminate our last remaining R12.

Have a great day,

SMS - get your 609 certification - costs about $20-$25. Once you have that, you can buy your own R-12.

As Larry posted elsewhere today, R-12 is getting cheaper. It's ALOT cheaper than retrofitting an R-12 system for R-134 which in my opinion is not very effective in a car that was designed for R-12.

After you have the juice in had, search around the archives here for tips on "hot-wiring" the pressure switch on the receiver dryer. When a system is bone dry, it will not engage. You hot wire it to charge it up and possibly add a little dye while doing this to help locate the leak.

I'm not suggesting that a couple of cans of R-12 is cheap. I am saying it's cheaper than most any other approach and as Larry pointed out, you don't end up with a "mix".

My 2 cents.

PS - Kinda strange that we're talking about R-12 in January?

sms states "there is no freon in the system".

I'm NOT suggesting a mixture or "top off", but rather a test and then EVACUATION. Total flush of system would suit me fine also, since it's been inoperative for a while. My use of the word "compatable" refers to the dessicant material in the dryer, refrigerant oil and "O" ring materials used in the R12 system, not inter-gas compatability.

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

I owe an apology here. I mixed up some threads and thought that it was in this thread that it was suggested that R12 be MIXED.

I get in too big of a hurry sometimes.

I would like to comment on flushing. There is no need for the use of flushing agents unless there has been a compressor failure, or you are converting to a different refrigerant or oil type.

I'm now having to think about a/c stuff, which I'm not accustomed to this time of year.

What you need to do, sms, is put a set of gauges on the system and measure static pressure. If the static pressure is below about 82 pounds, then it is indeed empty of refrigerant and you can proceed toward looking for a major leak and see if the compressor turns free and makes pressure.

If the static pressure is 82 or thereabouts, then it has some refrigerant remaining and you may be looking at a fuse or control problem of some sort. In this case you can still have a bad compressor, but keep in mind that the failure of the compressor is more often a shaft seal leak, than a failed compressor itself.

There is no need to short anything to charge the system if it is just low on refrigerant. The static refrigerant charge will bring the pressure up so that the low pressure protection switch is actuated so you can finish charging with the system running.

The only need to jump the low pressure switch is to see if the compressor clutch will indeed engage. You should do this before turning the compressor by hand to ensure that it is free.

Best of luck,

Larry et al,

I have about 20lbs of R-12 on hand, but don't want to waste any on just a system integrity test. I like the idea of using something more affordable like R-22 with Nitogen for the system test, but am not sure how I go about getting compressed N2. Any ideas?

Thanks much,

Steve

You can search and find who sells industrial gases in your area and buy the smallest bottle you can get. The deposit on the container will far exceed the cost of the contents.

You will then have to get fittings to adapt from bottle regulator to your manifold gauge set.

I totally understand your hesitancy to put even one ounce from your R12 cannister into a system that you are not sure is tight. I only have about five pounds left in my cannister and I'm scared to death of using it up. A 30 pound tank is now about $600.

Do you have a sniffer?

Good luck,