converting r-12 to 134

[chefdanny121]

anyone have any experience converting to 134.......i was told to vacuum the lines to get all r12 out of system!!!! any advice would be greatly appreciated!!!p.s. bought conversion kit at autozone....
thanks, daniel

[632 Regal]

need to replace the drier and "should" change the oil out too.

[winfred]

take the kit back as the fittings that come with those kits are usually aluiminum **** that depend on the valve in the old fitting, a good conversion fitting is steel with it's own schrader valve in it (you remove the old valve core) change the expansion valve and while you are there pull out the evaporator (about 5 extra minutes) and look for oily spots (if it's oily it's bad) and clean it, blow everything out with air or get a flush kit to get most of the old oil out, drain the old oil out of the compressor and refill with 6 ounces of ester oil, replace the receiver drier and you should be good to go to vacuum down the system, about 45 minutes should be long enough to get it clean and dry, the system will take a touch under 3.5 pounds (it doesn't need to be exact just close) 12 ounces to a can 16 ounces to a pound

[upallnight]

Replace the drier and fremove as much of the old oil out of the compressor as you can, Fill with new oil that is compatible with 134a. I think ester or Pag.

[GS535i]

Do the E34 chassis R12 system AC hoses qualify as 'barrier' types normally specified to contain R134a? Similarly, are the O-rings compatible?
On some Porsches, it is common to have the hoses removed and their fittings rebuilt as barrier type hoses and all O-ring material type changed - so am wondering if this has any relevance here.
my R12 system is still cooling ... hopefully for a loooong time .. but just in case ...

[Gene in NC]

Maybe not convert. r134 cost has gone up while r12 has come down. Shop cost for 30 lb now about $250 for 134 and $400 for r12. Check with shop re their price.

Sam's has 30 lb 134 for $254 and you can buy it.

[632 Regal]

nope the hoses will eventually leak all the r34 out...not the newer barrier type. Might be looking into new hoses or you will be adding and vacumming probably every year, should probably replace the drier each time too because of atmosphere.

[winfred]

i've never had a problem with them, i have a few customers cars that have been converted 5 or more years and not counting component failures that cause a dump they are still going strong

[632 Regal]

well I stand corrected! They arent supposed to be barrier type, maybe bmw was overly protective anyways?