In process of replacing head gaskets due to combustion in coolant that caused overheating and eventually white smoke from tail pipe.

After removing both heads, there were no visible signs of blown gaskets. There was major clogging in the passages near the firewall.

So looked closer for signs of slipped liner.

The cylinder closest to the firewall appear to have a small gap below the surface, but not all the way around.

Is this a slipped liner...?

 

Okay, pictures are not the best...but...l've added some markers to distinguish different areas.
White markers are cylinder bore.
Red dots are along lip of liners outer edge, which is flush with block surface. (you can faintly see circle that goes around bore about 3/16)
Yellow marker is top of piston.



l'm not seeing any signs of slipped liner. Circular ring, liner edge, looks firmly in place and is flush with block surface and there doesn't seem to be any "steam-cleaning" on piston surface.

That ridge/groove round liner upper edge is unusual, for sure, but, not sure if it was done by sloppy piston (bad rings) or made by someone in there previously (ring ridge removal tool) or poor machining from manufacturer.