Steve Foley wrote:
Are the comments in parentheses yours? It's kind of hard to tell who wrote
what.

In any case, I know of at one Lycoming engine designed for a boat. I think
it was used in the 1930s.

Lycoming, like Continental, built a wide range of general purpose
liquid cooled engines which were used in the "assembled cars" as well
as trucks, compressors, gensets, boats, etc. Continental did more of
that and the flathead fours and sixes in Kaisers and Henry Js were used
in welders and whatnot up until four or five years ago, new. They also
made a lot of truck diesels and multifuel variants thereof for the
military. Lycoming flathead V8s were used in Cords and Lyc built the
last of the mighty J and SJ Duesenberg engines as well. They had a
proud history. But their management got senile and ossified and only
type certification kept their dead carcass propped up aoll these last
40-50 years.