AC Charge

[diesel freak]

I am attempting to recharge my 1986 Diesel Golf with 134A. The Chilton Manuel states that it holds 40 ounces of R12. Is that a direct conversion for 134A? ( 40 oz of 134 equaling 40 oz of R120) ? What would my pressure reading be on the high and low sides with 134A , would they be the same as the R12 readings?

[bscutt]

does it have a window on the cannister (forget the name, sorry..) that's on the low side? Site glass. If so when I did a conversion on my 81 Dasher I could not quite get all the bubbles out, not sure why. However I did get a decent charge an my mechanic said to be on the safe side don't let the high side charge go above 160 PSI (it wasn't super hot out, maybe mid 70s). If you drained the oil from the compressor and put the correct amount of PAG oil in I would expect the charge amount would be similar but not necessarily exact. Low side pressure should probably be in the 35-40 psi range. Since the system wasn't designed for 134 I have found that it's a bit of an art and a science and gauges are essential to getting the charge in the right spot. If you are getting 40-55 degree air at the vents (depends on how hot it is outside) you're in the ballpark. There's lots of info on line about charging, pressures, temperatures, and so on.