Engine life expectancy

[Richard5]

The graph for engine mortaility is a bathtub curve. This would show how a rebuild can result in decreased engine life.

When one asks how much life is left in an engine what they really want to know is at what point is the cost of major maintenance offset by an increase in engine life. Funny thing that.

In WJPeterson's 1st post to this thread he speaks of how "many" folks talk of some hour figure as indication of an engine requiring overhaul (time before overhaul). The thing is, most of those opinions are simply that and should not be the basis for the decision to spend thousands of dollars.

I have found that the best opinion is an oft run engine is the happiest. The best one can do to increase the life of an internal combustion engine is to run it often. Run it to operating temp, then under load. Say, 55-75 rated BSHP. Engine oil analysis is the best indicator of engine life.

Perhaps as equally indespensible is having intimate knowledge of your engine. Knowing the care and feeding is of value. In this way, just as with regular oil analysis, you can spot trends in fuel burn, oil consumption, compression, or wear indications.

[Rakuflames]

Originally Posted by Wjpetersen

Thank you Pete. I have a mechanic coming by next week to give me another analysis and provide a quote to rebuild.

I am a new owner and don't yet know how to captain a 50' boat yet. Why do I need to use them a lot? I turn them on once a month right now. But won't actually navigate around for a year.

Diesel engines were designed not only to run but to work hard. They aren't happy only being used at near idle speed to putt-putt in and out of the slip. No matter how much you like sailing instead of motoring, honor your motor.

Find the manual online if you don't have it, read it from cover to cover and do what it says (and it will say to use that engine). That engine is sometimes your first line of defense when the snap hits the fan. As a new sailor, for instance, it's just *possible* you'll run aground ... not that it's ever happened to me , but I've "heard" that your engine can sometimes help you get off.

[Rakuflames]

Originally Posted by Nadejda

There is no set amount of hours a marine diesel will last. It depends a lot on how they were run, the maintenance, and how well they were built in the first place. Hours are ambiguous, the best measure of longevity is gallons of fuel burned. You could have two engines of the same make and model one is in a sailboat and pulls only forty percent of rated power and the other in a power boat that pulls eighty percent of rated power, both engines will burn approximately the same amount of fuel before overhaul but the sailboat will have twice as many hours as the power boat. That said a Detroit that is well maintained and not being pushed to hard will be just getting broken in at the 10K mark.

Oh yeah -- check your zincs often. My old diesel was ruined because the idjit before me did not.

[Wjpetersen]

Wow. Great advice all. I am finishing my captain's course and will start taking the boat out once a month. Of course, after reading the manual and checking with the mechanic.