I have lots of experiance converting 12 to 134a, and will soon be hooking up a 134 system in my own car (65 Polara). Basically, 134 will cool just as well as 12 while you'e moving, but will not cool quite as good as 12 does sitting still. But for the price, you won't notice any big difference. The important thing is that when converting, you reseal the entire system, replacing all o-rings with new ones, and lubricating those new o-rings with Ester oil (the oil you use with the 134 system). You must also drain the compressor of its oil and refill it with the Ester oil that comes with a conversion kit. The idea is to get all the old oil out of the system. Use a high pressure air nozzel to blow out the condenser and evaporator. When doing this, its a good idea to hold a rag over the other end so you don't make a big mess. You must replace the accumulator/drier. You must replace the orphus tube if your system has one (most Mopar systems use an expansion valve, which may or may not need replacement, I've never converted a system with an exp valve before). As far as the fittings go, there are three different types of 134a adapter fittings. The kind that are hollow all the way through (a), the kind that have a valve and rattle when shaken (b), and the kind that have a valve and don't rattle (c). To install: a & b. Lube the inside with ester oil and attach to original R12 fitting. c. Remove the shrader valve from the R-12 fitting, lube 134 fitting, and attach to original R-12 fitting. Seal the whole system up and then evacuate it for 30-60 minutes with a vacuum pump. Make a special effort not to allow the drier to be exposed to the atmostphere for more than 15-30 minutes (moisture will ruin a drier). Charge it up with 134a and you're ready to go. Dave Casey ----- Original Message ----- From: Scott H <kneedrager@xxxxxxxxxxx> To: <L-FORWARDLOOK@xxxxxxxxxxxxx> Sent: Friday, May 04, 2001 9:17 AM Subject: [FWDLK] Any AC experts? > Does anyone have experience converting older a/c systems from R12 to r134. > I have heard mixed things about efficiency and would like to hear from an > impartial party that know the facts. > Scott > _________________________________________________________________ > Get your FREE download of MSN Explorer at http://explorer.msn.com
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