My Dusty 71 GMCe Electruck

[Gregski]

here I'm checking the radiator to see if it holds pressure, it doesn't need mutch 15 PSI I think (correct me if I'm wrong) but what ever it is 5, or 10 you just want it to hold it there while you go pee or get a beer or both, the purpose of that is that you raise the pressure to raise the boiling point, blah blah blah

and man if you don't got one of these Mityvac pumps git one, they also make a vacuum pump, also very handy, anyway they used to be made out of metal and in the US if I remember correctly now they are plastic, but still OK