Those monster machines are really cool! When I worked in the oilfield he had to go to Houston's Stewart & Stevenson shop where some of our big fluid-blending trucks were being revamped. There were some ship engines there, which were a "modular" inline design that could be ordered in many configurations, and were considered a "low profile" design for 'small' ships. The cylinders were more than 3 foot bore (I think it was 40") and could be as big as 6-foot bore, each cylinder got bolted to the last one as they built the engine. I was invited (and did!) to stand on the piston of the last cylinder that had been bolted on, I was waist-deep in the stroke, up to the deck: it had over 5 foot stroke! The intake and exhaust manifolds were being bolted to the head that was hung above me, also mighty big, so I didn't stay in the engine very long(!).
One of the guys I worked with had been on some of the [older] large oil tanker ships, used to move crude from the Mideast to USA back then. He was an engine mechanic: the ships' 3 engines were "walk-in" design, where you put on a raincoat and helmet (like an astronaut helmet) if you wanted to walk into the engine under the crankshaft while it ran (dangerous!). The doors into the crankcase area were rubber-gasketed all around the outer sides (still greasy) and the crankcase was almost 10 feet high inside. The engine received oil into the rod bearing from an individual pump on each cylinder, and inspection was required every 4 hours while running at sea. Sometime they would shut down the engine being inspected: then you just needed the monkey suit and not the helmet, which made things much easier to check and see. The ones he serviced were 2-stroke diesel types, fuel being fed by large pumps and sprayers making a supercharged-type fueling system. Cool stuff!
