Thanks fellas with all comments to date,
This engine is awaiting parts.
I am feeling more confident about this engine now.
So I have ordered a new piston with cast iron rings, plus a gasket & seal set.
I was told by the supplier that I didn't have any choice with switching to chromed rings. The chrome rings do not fit the piston and if your engine didn't use them at the beginning, then you can't switch. And also that the cast iron rings will "break-in" the walls faster than the hard chrome, which take longer.
I haven't done any experiments to know any difference here, so decided that by not changing from original was best.
Thanks again.
