[TomballMottershaw]

thanks,
good questions:

re Q1: --> no water bubbling up in Radiator

re Q2.) not a chipped valve as they looked good when we had the head off.
but some sort of valve sealing issue is possible.

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I'll do a cylinder leak test next.

But I omitted the puffs of smoke from the oil filler tube tube a low idle speed.

this is why I think it's the rings / Cylinder wall leak.