Just spent a little more time tearing down the Lark.
The lower cylinder may get by with some honing,
a new piston, and rings, but I haven’t done much for
measuring other than determine the cylinder bore is
a little over 3″ diameter.
Big chunk of the piston ring lands are “gone” and some
of the rings fell to pieces.
I haven’t finished playing detective yet, but I didn’t see
anything missing that the piston may have ingested.
The spark threads look in good shape, original, and no
heli coils in them.
If I find anything definitive, I’ll check back, but perhaps someone
will have more ideas after looking at the photos.
Prepare to be boarded!