Thanks eddy. I have found some info on checking the chain marks and that is where I will start. If it is gasket or valve problems the chain/cover will have come off anyway. I think the tensioner is hydrolic, but info is sketchy.

The valves seen to be closing fairly well when positioned with lobes up and compressed air applied.

The zero compression is a puzzle. There is a TSB that says
sticking valves caused by low quality gasoline will cause this. Says use top end cleaner... so I pour some seafoam/gas/oil mix in the hole and shoot air in with valves near closed. Still no compression when cranking.

I will start tearing in to the chain covers.