The gas line solenoid the first check, 12 volt & when the key is turned on it should energize & allow fuel to flow to regulator. In & out of the reg. the next step.
This, and I would plan on ordering a rebuild kit for the converter/vaporizer. When we ran our trucks on propane at my job, we would rebuild them every year. If iirc, they were a impco product. They can get quite dirty and impede the flow of fuel.
Good luck!
