I have a 1964 vintage car with an A/C system that has a Tecumseh type compressor. It has shut off valves. This system was professionally converted to R134 and has a blue plastic cap on the low side. It worked fine when I received the car, but it's been in the ICU for 6 years and the gas has leaked down.
I'm NOT R134 savvy, but have charged a few older (R12) systems, the kind that have Schrader valves in the ports. This one doesn't have Schrader valves and I'm trying to figure out how the shut off valves work. I've already, once, vacuumed the system and purged with Nitrogen, then charged with R134. When I turned the valves to what I thought was isolating the system and removed the charge hose, all the gas blew out in my face.
The valves don't seem to operate in a manner that's intuitive. Can anyone explain the ins/outs of the valves?
thanks