I picked up a leak-down tester and have a question about the input pressure side.
It's a standard tester. There's an airline in to a first pressure gauge which reads 1 to 100psi. This gauge has a regulator. Then their a restriction after which there's a second gauge. The second gauge read in percentage 100 to 0 %.
The opereration is to input pressure and zero the second gauge to zero percent leakage. The gauge set is then connected to the sparkplug hole. There's some expected leak which is read out on the second percentage gauge. It's a percentage of the pressure from the regulated first gauge.
I tested four engines and the leakage readings were what was expected for those engines so the gauge seems to be working fine.
The issue is how to change the pressure in. No matter what pressure I put in from the air compressor the the reading is always the same about 15psi when I zero the percentage gauge. If I set the regulator on my compressor to 20psi then zero the tester the reading on the first gauge is 15psi. If I set the regulator on the air compressor to 60psi and zero the tester it still zero's with a pressure of 15psi.
I would think that if I put in different pressures then the zero should happen at a different pressure on the tester first pressure gauge. It always zero's at 15psi no matter what pressure is applied from the source. Does that sound right? That for different imput pressures the gauge should zero at different pressures?
trouts1