one piece of advice I can give you, is if the trucks have not run in awhile, DO NOT ATTEMPT TO START EITHER TRUCKS WITH THE EXISTING GAS IN THE TANKS”. Doing so will cause the valves to stick and potentially cause catastrophic failure. Far too many ‘bolters in this forum have experienced this first hand. Either replace the tank and lines, clean them out, or use a temporary tank to hear your engine(s) run.
What he said. Been there, done that!
