Hez10 Posted June 12, 2008 Share Posted June 12, 2008 My AC blows warm, so I would like to recharge the system. How can I tell if I already have R-134A? I just bought the vehicle. Thanks Quote Link to comment Share on other sites More sharing options...
914lps Posted June 12, 2008 Share Posted June 12, 2008 The 91 came with R-12 from the factory. If I was more then one can low I would convert to 134a. If your car has allready been converted, the fittings will be diferant then the ones for r12. Any shop that does AC work can tell you if the fittings are old or new. The old r12 have a thread on them. 134a have no threads on them. They are more of a quick conect . You can get a conversion kit for around $40.00. Just make sure to have the system vacumed down before converting and adding the 134a. If you have any r12 in the system some shops will vacum the system down for free just so they can recover and resell the r12. Quote Link to comment Share on other sites More sharing options...
Hez10 Posted June 12, 2008 Author Share Posted June 12, 2008 The 91 came with R-12 from the factory. If I was more then one can low I would convert to 134a. If your car has allready been converted, the fittings will be diferant then the ones for r12. Any shop that does AC work can tell you if the fittings are old or new. The old r12 have a thread on them. 134a have no threads on them. They are more of a quick conect . You can get a conversion kit for around $40.00. Just make sure to have the system vacumed down before converting and adding the 134a. If you have any r12 in the system some shops will vacum the system down for free just so they can recover and resell the r12. Thanks for the reply and help! Where can I buy a conversion kit for $40? Quote Link to comment Share on other sites More sharing options...
JENunnez Posted June 12, 2008 Share Posted June 12, 2008 One more thing r-12 systems use mineral oil and r-134 uses a ester oil or a synthetic Pag oil. R-134 does not like mineral oils it turns the oil into a goo. Thereby distroying the compressor. You need to take the whole system apart and flush everything,including the compressor, with a a/c flushing solvent that takes the mineral oil out and evaporates completely leaving no residue. Then replace the oil with the correct amount to each component of the system,evaporator.condenser,compressor and receiver dryer. All this is done with a speacial bottle that can be connected to compressed air to be able to blow the flush through the components and also used to charge it with oil. Also need to change the receiver/dryer since you can't flush that. Then you can vacuum the system and charge it. In other words let a A/C tech do the job. Quote Link to comment Share on other sites More sharing options...
90LS400Lexus Posted June 18, 2008 Share Posted June 18, 2008 The A/C on my 91' was weak, so I took it to my cousins shop that does A/C work and while I assumed it was still R12, he said it had already been converted to R134a. The fittings looked larger than I had normally seen on older cars, so I guess thats the easiest way to tell. He recharged for $25 and now it blows out ice cubes! :D Quote Link to comment Share on other sites More sharing options...
eatingupblacktop Posted June 18, 2008 Share Posted June 18, 2008 The a/c system is too expensive to play with if you're not experienced. As JE suggests, take it to an a/c shop. Even if the conversion's been done, just topping it up, it's easy to overfill. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.