Totally agree
I've run Detroits in boats since 1961, and generators before that. I wouldn't have anything else on the ocean for reliability. I ran 6v53s and all manner of 71s in the navy. My first boat was twin 671s and my current boat (probably my last) boat has twin 671. The blocks are from 1947, never overhauled until I did it a few years ago. Parts were no problem.
There's a lot of used parts on ebay. It's a good time to pick up spare pumps, etc. I go to remote places, so carry a lot of spares. Although I've never had a failure with the current boat. Keep the fuel clean and the injectors will last longer. I haven't changed one since the engines were overhauled, about 10 years. Some years I put on 500 hours.
Don't let the average marina mechanic work on Detroits. Better to learn yourself.
I'll be running Detroits until they take the starter buttons from my cold dead hands.
Leaky? Yup. Loud? Yup. Reliable? Omg yup. In my humble opinion, after 30+ years on ships of all sizes, the /53, /92 and especially the /71s are without a doubt some of the most rugged and dependable engines ever made. So simple! I’ve had them on a variety of smaller boats as mains and generators, without a single major failure. And there’s a reason why every ship I’ve ever worked on had a Detroit Diesel (8v92s and 6-71s mainly) for the emergency generator: the start, they run forever. I also agree that it’s easy enough to work on them yourself.
Two very important thing2, though: In today’s world of desulfured diesel, you really need to watch out for injectors. These new fuels have terrible lubricity and have caused major problems on ships. If you can figure out an arrangement, I’d look to putting in some sort of pre-lube pump system. That way you don’t have to rely on Fuel pressure coming up as the engine starts. On EDG units they often fit a hydraulic accumulator that stores oil pressure for start-up, this minimizing wear. So when I say “pre-lube” I’m referring to something to get fuel circulating, not lube oil. Although, it’s always a good idea to have some sort of pre lube oil system too, on any engine.
Second, if you ever do need to replace an injector, MAKE CERTAIN that the fuel supply and return lines go on perfectly. On Detroit’s, these number lines cross over the top of the valve train at each cylinder, so if they or the rocker arms are not on correctly, you’ll snap the jumpers. Then you’re going to bleed fuel into the sump and burn up everything with ruined lube oil. This is especially true on versions that have 4 exhaust valves instead 2, as the bridge between the valves can easily bash into the jumpers if not seated correctly. (Don’t ask me how I know hehe)
Other than long-winded stuff, these things have literally been known to be bullet-proof - provided you have clean oil, clean fuel and decent cooling.
