I Didn't Know This

[Fish40]

I happened to come across a recent copy of "Sea Classics" magazine the other day, and they happened to have several articles about US sub operations in the Pacific. In any case, one of the articles stated that the arly Gatos were prone to engine problems. I was surprised to learn that a dozen early Gatos were fitted with a copy of the German MAN Diesel engine. These engines were manufactured under license, by HOR.

[Rockin Robbins]

Yes, they were monsterously problematic, with muchas scored cylinders and engine failures. Several subs had to have the things replaced. Was that the Fairbanks Morse engine? Whichever manufacturer it was, they were trouble with a capital "t." Wish I recalled the book that told of the problem or the submarine it was about but I'm drawing a blank right now.

[Fish40]

Hi RR! I didn't see anything about the FM Diesels. I believe engines from GM, and FM replaced these earlier ones and became the standard on Fleet Boats.

[Torplexed]

Clay Blair in his book Silent Victory spends a lot of ink on the infamous HOR engines. Since, H.O.R. (Hooven-Owens-Rentschler) was the US licensee for M.A.N. which made the German diesel engines a rumour went around that the designs had been sabotaged on the drawing board by the German parent company.

Given their temperamental reputation the crews called them 'wHORes.' ;)

[mcarlsonus]

...and ultimately replaced by modified Fairbanks Morse and GM-Winton locomotive engines. The GM-Winton was a V-16, while the FM was a 9-10 piston opposed affair - there were two pistons per cylinder whose combustion chamber was the dished top of each piston. They moved toward and away from each other in the cylinder. Odd design for those familiar with your typical automotive internal combustion engine!
Yes - the HOR's were built under license from Germany's MAN. "Deliberately sabotaged?" Doubtful. More like "limited technology transfer." Like many military items, the stuff available for the export market, or available to be built under license, is limited as ones ultimate goal is to avoid a potential head-to-head with ones own most-current technology. Perhaps it's useful to point out that MAN propulsion units had been successfully utilized in marine applications and had been installed in early WW1-era U-Boats.