[joe'stoy]

Has anyone used and been happy with the Harbor Freight leak down tester.
I am reading that it limits the air pressure into the cylinder to approx 15 psi.
It looks like Jegs has a leak down tool that will allow up to 100 psi into the cyl. Does the higher pressure give a better test and provide more info.
NEXT question, I am at my bench trying to test the HF tool. I follow the instructions, twist the pressure regulator till the second gauge is at its "set" point, then hook up the hose to the spark plug adaptor (sitting on my bench) and I expect a 95 to 100% leakdown because the air should just flow out the adaptor. But nothing comes out?? Any thoughts/comments would be helpful.
Joe