msmith, that's not the impression that web site gives me.
Universal's first engine in 1895 may have been a marine design, but by 1924 "...the Universal Model K series of 4 cylinder industrial engines was developed for use in powering generators and pumps."
So long before the A4 engine was designed, Universal was designing and selling purpose-built non-marine engines. Which one of them was the design basis for the A4? Really? How do we mind-read the inspiration for the design?
Certainly with a compression so low, it doesn't seem like a purpose-built recreational boat engine, where weight and performance count as much as durability does. That part of the design alone would seem to indicate it was inspired, or based on, something designed for extreme long-term use, i.e. an industrial or perhaps tractor engine. (Although I've never heard tractor accusations before, except for SAAB's? 3-cylinder.)
Either way it certainly has outlived an awful lot of their other designs!