Low Compression Before SC Install
Thread Starter
Rennlist Member
Joined: Sep 2003
Posts: 422
Likes: 1
From: Ann Arbor/Hell, MI
I made a leak down tester out of the compression tester that I purchased (Schrader valve removed) and the regulator from my compressor.
All of the cylinders were between 95 and 100 psi including #7. The air leakage that I could hear from all of the cylinders was consistent, including #7, so I could not tell if it was is the piston ring, intake or exhaust valves. I put the Schrader valve back into the compression tester and rechecked #7. It came in at 120 psi again.
I will be removing my cam covers to check/advance timing, check cam clearances, and paint/power coat the covers, so more detective work ahead. Let the SC install begin.
All of the cylinders were between 95 and 100 psi including #7. The air leakage that I could hear from all of the cylinders was consistent, including #7, so I could not tell if it was is the piston ring, intake or exhaust valves. I put the Schrader valve back into the compression tester and rechecked #7. It came in at 120 psi again.
I will be removing my cam covers to check/advance timing, check cam clearances, and paint/power coat the covers, so more detective work ahead. Let the SC install begin.
Burning Brakes
Joined: Oct 2004
Posts: 877
Likes: 2
From: Suburban St. Louis in Illinois.
Sharks... How did you do the test ? If you put each cylinder at TDC firing...all the valves would be closed on the cylinder being tested...so, any "leakdown"....would be evident at the MAF....the exhaust...or the dipstick tube. Put a regulated air pressure source on the cylinder, listen at the intake, exhaust, and dipstick for leakage,,then shut off the air supply, and measure how long it takes the for pressurized air to bleed down and record the results. At least thats the way I did this test.
