[Supras] No AC on 86.5 MkIII w/ R134A conversion

[Jim Wooden]

Well some years back I converted my AC to the R134A as, at the time, 
R12 was very expensive and I had some leaking o-rings that required 
disassembly of the system.

On the advice of a mechanic buddy that had done a number of these 
conversions we did the "simple" conversion which consisted of adding 
PAG oil and "special additives" via a kit from Quest then recharged 
with recommended amt of R134A

Worked fine for two years then just didn't seem nearly as cold any more.
I took it back to him and, finding no serious leaks, he just hooked 
up the AC machine pumped it down and loaded a fresh charge.
Well... its two years later AGAIN, and although there is still some 
charge in the system (sight glass shows pretty full) I get ZERO cold air.

I have heard the R134A cars (esp. the conversions) are much more 
sensitive to being low on charge, and that could be the case here...

Does anybody have the recommended high-side/low-side pressures for a 
MkIII R134A conversion handy?

Other suggestions appreciated also  ;-)

Thanks,
Jim W.
original owner 1986.5 MkIII