I just bought a compression tester as my old one is inadequate for the job anymore..... it's simple has fittings for different spark plug holes and has the check valve ar the spark plug hole end of the hose to the gauge...
....it'll be here March 4th or so ...it cost $29.00 plus shipping and the total comes to $32.00
I'ed put up a link but I lost it... i'll add it when Amazon sends me a conformation of the order.....
.... here's the link...
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
.....
Bob.