Hi Bob-
The sight glass is just too dark to see ANYTHING.... :-(

With R-134, I believe the pressure should be about 80-85 lbs.(both sides) with the sytem off, and 20-35 lbs low side / 150-250 high side with the compressor running. Please correct me if that's wrong...

If anything, I've got a touch too much pressure, but that wouldn't be the cause of there being no differential while it's running.
At least it's not leaking out, but I still need to fix something here... :-(

Thanks.

__________________
Barry