Big Block Billy

A bad ring groove will cause the ring to flutter.This can break a ring. This could be because of excessive wear, or pitting in the grooves or a worn ring if re-using . An aluminum piston can wear out an iron ring just like it can wear a steel wrist pin. A reputable machinist took a look at a set of forged pistons I had and told me they were junk. The motor had sucked water, and the ring grooves were less then perfect. Nobody can really afford to play around with junk ! The best built boats still can develop problems. Check everything , And when you think it's ok, check again, if in doubt throw it out. I had to learn the hard way , when I was younger I didn't have the $$$ and patience.
I ended up wasting time and money. Now I have the money, and my time is more valuable ! BBB

Reed Jensen

BBB is correct... I've seen broken rings in engines before and in most cases it was new rings being put on used pistons... I call this a hillbilly rebuild... more often than not.. the cylinder has more wear than the rings... but by just putting on new rings and grinding the valves... Cleatus and Harvey can then say they rebuilt the engine. The ring lands on worn pistons aren't perpendicular to the piston any more.. they have a worn taper. Putting on new rings causes the rings to flutter and be deformed within the ring lands. This leads to fatigue and breakage.