289 Low Compression on Two Cylinders
A couple of weeks ago, my 289 started running poorly practically overnight. One day, ran fine...next day, go out for breakfast, and can't hold idle at stoplights, etc. The carburetor is a 600 Holley. I figured it had to be a vacuum leak, and checked all over the intake, but no luck. Even switched out carburetors, but no change. I figured I'd check the compression, and six of the cylinders were at 175-180 on the gauge. However, cylinder 2 was at 120, and cylinder 5 was at 105. I squirted oil in the spark plug holes on these two cylinders, and the compression went up - 140 on #2, and 120 on #5. It appears it could be bad or worn rings, but overnight? I pulled the heads and checked the valves, and this is what I found. This is the intake valve from cylinder #5.