[Fasteddie]

Four pounds of 134a is about right for the dash system. Your low side switch should not be cutting out at 30. It should cut out around 15 to 20. Can you jumper the switch or run a 12v hot to the compressor to force it to run long enough to get lo and hi readings? I can think of several possibilities. One, you have a huge leak and don't really have 30 psig when the compressor is running. Two, you have too much in the system and the hi side switch is cutting you out. Three you have a clogged expansion valve.

We tried to replace the expansion valve, tried two valves one was a four seasons cross that Creslie Clark gave us and neither one would screw on the end. So we cleaned the old one and put it back on. We also jumpered the low pressure switch and the clutch stayed on , but unit would not cool. It will only cool while you are putting freon in. As soon as you stop,it will run for 20sec and clutch will disengage at just below 30 psi