Cylinder leakage test

Kirk Morgan · 10-31-2024, 07:39 PM

Here is some detail to my findings. This is a Nitrous engine which was chirping out of the left bank after a run. Iam not a Nitrous person but a N/A engine person. Ran the valves all was good. Ran a compression test not good. The compression was a roller coaster from 200 PSI to 50 PSI. Un adjusted all the valves and removed the rocker arms. The 50 PSI was a exhaust valve leak with 80% leakage and the 200 PSI is 20% leakage. I have a cylinder leakage tester and they way i use it i turn the pressure on one side to 100PSI and read the other gauge to see how much leakage there is. To me the 20% leakage on the 200 PSI cylinder is to much i was always trying to get in the 10% or less leakage range on engines i have built. I have never built a engine with gas ported pistons. BTW i always spin the engine over 5 revolutions when checking static compression.
Thanks

10-31-2024, 07:39 PM	#5
Kirk Morgan Member Join Date: Jan 2009 Posts: 230 Likes: 1 Liked 81 Times in 45 Posts	Re: Cylinder leakage test Here is some detail to my findings. This is a Nitrous engine which was chirping out of the left bank after a run. Iam not a Nitrous person but a N/A engine person. Ran the valves all was good. Ran a compression test not good. The compression was a roller coaster from 200 PSI to 50 PSI. Un adjusted all the valves and removed the rocker arms. The 50 PSI was a exhaust valve leak with 80% leakage and the 200 PSI is 20% leakage. I have a cylinder leakage tester and they way i use it i turn the pressure on one side to 100PSI and read the other gauge to see how much leakage there is. To me the 20% leakage on the 200 PSI cylinder is to much i was always trying to get in the 10% or less leakage range on engines i have built. I have never built a engine with gas ported pistons. BTW i always spin the engine over 5 revolutions when checking static compression. Thanks