[Young1]

After performing a compression test cylinder 7 had 45 pounds and cylinder 6 145 pounds. All others are 185 to 195 pounds. Thus the reason for excessive blow by. Pulled one head, pulled 2 pistons and discovered cracked piston lands and rings. The head gasket was fine. On cylinder seven I could pull off two pieces of ring land if I tried. What could be the cause? The only thing I can think of is some fuel boil over at heat soak. This engine has probably only revved to 6000 RPMs 10 times in it's 14,000 mile life. 38° of timing all in at 2600 RPM.