Wow, I dont think I'd want propane in my ac system, sounds dangerous. Would an ac system hold enough to be a time bomb?
I too have converted many systems to 134, I usually spend the extra money and replace the reciever/drier to remove any old r-12 contaminants (I'm very cautious) . Pulling a vacuum is really the best way to get a the a/c system in good working order and it also tells you if your seals are good (if it looses vacuum after drawdown). I have had many "Professional A/C Techs" "tell me those kits will lock up the compressor". I have had my old 85 GT converted for about 6 years with no problems. I believe the compressor oil is the PAG type for 134.
That is a big no no and is consider toxic waste when the 2 are mixed. We have to identify the refridgerent before servicing a vehicle. On Fords you should install a high pressure cut off switch. I learned after doing many retrofits, you get what you pay for. In this case you should replace the compressor, flush out all the old oil with d natured alcohol, replace the reciever dryer, install new oil compatible with r134a, vacuum system down for 45min to1 hr. Install r134a at 15% less charge than r12. Never seen one come back using the described method above. Have seen many come back other wise.
any freon is considered a "hazardous material" and "environmental pollutant" when you dispose of them, they are supposed to be in an appropriate container and labeled accordingly. mixing them creates "hazardous waste" . as long as it is in an enclosed system there is no more or less danger from the two mixed together than the seperate materials. freon 12 is MORE hazardous to the environment. 134 is still an environmental pollutant and hazardous material strictly by its self. Personally, having worked in the hazardous waste and material industry for 16 years, i never bought the government lie that switching was going to save our environment. just like with CO they blame cars as the number one source of freon release. in both cases companies release daily tons of this into the environment. if they get caught they just consider the fines part of the cost of doing business. if they dont get caught they lie about how much they released and sell their "excess pollution rights" (the pollution and exhaust they paid to be able to release and didnt) to other companies that admit to having released too much. thus helping that factory pay less of a fine for the amount they released. sorry guess im getting political, which i hate. charge it with what you can get and what works best and enjoy the cold im not using
I have converted a couple systems. Use Ester Oil for the 134 Conversion. Flush the entire system making sure you simply drain the compressor very well. Replace the dryer. Replace the expansion valve if you can/want. Add the required amount of ester oil to the compressor pull a vaccum for as long as possible should have 29.9hgs around sea level then charge. Very important to not let any air into the system!! Like said before a converted R-12 to 134 just just not work as well on hot days. Do not go by the sight glass like on old R-12s as 134 has different fill rates. Go by the high pressure side and how much cold air the system is pumping to determine fill. The high pressure should be 2.2 to 2.5 times the ambient outside air temperature.
When i first went through the A/c system in the Mav(new pump, hoses, drier, etc) I put R134 in it, worked great going down the highway, but at a stand still forget it. I drive a 91 Dodge with a Cummins diesel and the wife drives a 92 Bonneville, both factory R12 systems. For years now Ive been dropping HC12a in both of them and they still work great. When I had trouble with the Mave I sucked the 134 out and used the same thing in it, performance improved, although its still not 100%, I think it should improve if I take the time to throw the fan shroud on it. Also noticed that the 134 really put a load on the engine especially noticable at itle, the hc12 seems to run a lot easier and at a lower high side pressure. I agree, use what works best for you, it seems like every system reacts a little different. Ive heard lots of different things about oils and such, the only thing I know for sure is dont run mineral oil with R134. Otherwise Ive used Ester and Pag with 134 on customers vehicles and never had a comeback.
you going to love this one,I have a 92 jeep Air did not work so I ask my wife to take it to shop and ask how much to change it over to 134 from r12 they told her it would be 1300.00.[ha ha ha] she told the guy that she had to call her husband and let him know before she spent that kind of money. then he started backing up on what he had price, he came all the way down to 250.00 how that for trying to stick it to a women.i know it is off the subject but i though that u all might like that
happens every day, you need a belt, but they want to sell you a water pump, alternator and the belt....
