Thanks for sharing photos Luddite,takes me back to serving my apprenticeship at Doxfords marine engine builders Sunderland.Test bed running would be 24hours for 3/5days and at certain revs600/750 those massive marine engines would shake and vibrate like a Morriss A engine in a car.especially on sea trials.Notice cat at control engineers feet, the rough and tough marine engineers of heavy engineering were all softies at heart coming into the machine shops at holiday time to feed cats.Cheers
I've sailed on a Doxford engined ship, quite an experience, but your mind must be playing tricks, the big ones never revved at 600, more like 110 rpm.
Here's one (or rather two) in action. Go straight to 6.15 mins to see the top pistons showing their skirts and the rubber hose arrangement for water cooling.
https://www.youtube.com/watch?v=5k6sOQLKuro
