MK_951

So I converted my A/C to R-134 and I was wondering how many lbs. of refrigerant I put in. I know R-12 is way better and I believe that it also is more dense so the system requires less to put in. Any suggestions?

djantlive

no, it's the same, 2 lbs. don't overfill because it'll actually make the ac system less efficient and make it less cold. my ac shop played with the pressure to see if the system gets colder. it didn't change. while not ice cold, the r134 did work. r12 that was in there wasn't that much colder actually.

m73m95

No no. You should only fill the system to 80% of the r12 capacity.

33oz r12 system will take ~26.5oz of r134

CurtP

According to the Porsche technical bulletin, retrofitting a 944 to 134a takes 860g which works out to 1.9lbs.

MK_951

K..so A/C blows cold and everything seems to be good but now my alternator isn't charging out of nowhere and it is a brand new alternator only 1month old

djantlive

are the belts properly tensioned? did the compressor get changed? if so, maybe the belts tension is the issue causing alternator not charging properly.

MK_951

I'm gonna have to play around with the tensioner then..cause it squeals all the time even when trying to drive

Ben951S

Lol, so what are you waiting for, flashing lights too or a phone call from your car? Go fix it.

griffiths

So I converted my A/C to R-134 and I was wondering how many lbs. of refrigerant I put in. I know R-12 is way better and I believe that it also is more dense so the system requires less to put in. Any suggestions?
Follow the Porsche TSB of charge weight as a reference, but ideally you want to charge by "P&T", pressures and temperatures.

I'm gonna have to play around with the tensioner then..cause it squeals all the time even when trying to drive

A squeal could be caused several things:
grease on belt,
old belt,
tensioner going south,
AC clutch slipping,
belt slipping,
alt bearing going south,
.... time to pin down the source.