Several years ago or decades? I am notorious for loosing track of time myself. For some reason I thought we still had a hospital ship named Hope but it appears not. I thought we had Hope and Faith. It appears the two in service are Faith and Comfort. From about 86 and 87. Hope went out in 46. Maybe we have been using the wrong name.I worked at the Ponca City Diesel Power plant while in college. The engines that drove the generators were the size of the OP’s pic. Nordburg diesels. I think the max speed was 180 RPM.
Pistons were 36-40” diameter depending on which engine they came out of and 6’ tall. Helped with a tear down one summer. After removing the pistons, stood on top of the piston rod and used a 4 lb hammer and chisel to chip out the carbon in the exhaust ports.
The engines were started using high pressure air to get the engines rolling and up to speed, then a mix of diesel fuel and natural gas was slowly introduced while the air pressure was dropped off until the mixture was finally right and the air discontinued.
Pics below are Nordburg diesel generators very similar to the ones in Ponca City. They are no longer used. Haven’t been for years. One engine was sold several years ago to replace an engine on the Hospital ship USS Hope that travels the world.