Spark plug gap closed fresh rebuild

^This

I have been the recipient of much good humored help on this forum, but as a machinist, and Like Ricko says "just because it's old, doesn't mean it's bad, and just because it's new, doesn't mean its good. I knew nothing when I started, now I know that, after 60 years of wrenching, 40+ years machining, there is lots to learn. Personally if that was my engine, it would be coming apart. If something has hit the piston, I would not want to find out when a hole has developed and you are oil blowing everywhere. Happened once to me.

A spark timing issue is not going to cause that. That's impact damage. The only thing that's going to impact a sparkplug electrode is the piston or something floating around in the cylinder. If you didn't drop that sparkplug before installation then there's a mechanical issue with that cylinder.

Cdog_96 said:

I didn't notice any chunks hanging around in the cylinder with the bore scope. There was small pock marks on top of the piston and some carbon flakes I believe. What should cranking compression be and do I just remove that plug for the compression test ?

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Don't know exactly - but north of 175 psi. Take out all plugs. Crank on each cylinder with the tester installed, let it pulse 4 times. you should not see a variation of more than 10% hole to hole.

@Cdog_96 any updates?

Meh