Re: 1940 - 356 engine ring job

Posted by Bill Butterworth On 2013/8/18 15:01:20

Tim, thanks again for the information. I believe the problem with #6 cylinder started with a leaking head gasket at #6 cylinder (white exhaust and low compression). The two oil passages in the # 6 rod checked out clear. I was concerned about just replacing the head gasket and not checking the head. It was cut .013" to make it true. The mistake I made was not checking the head clearance before re installing and bent #6 exhaust valve. Have sense found out via a copy of the Packard parts manual that two head gaskets were available (not counting the "extra thick" export gasket). The replacement gasket I used was the .060" not the .091", which would have worked. Since then I have another head (uncut) and have done a valve an guide job. Was able to stat engine one time after valve job then engine wouldn't restart. Did air leak down test and found all cylinders had 60% leakage into crankcase, no air lose at tail pipe or carburetor. Added 2oz oil and recheck showed good compression again. Pulled pistons and found rings collapsed into groves and very difficult to get out, lots of black carbon. Rings are now out. Rod bearing were previously replaced with .001" over size when I assume the.020" pistons and hardened seats were also installed. It also appears that over sized pins were installed at that time as the wrist pin bushings look quite worn. That's the whole story.