small diesel motor Life Expectancy?

[bobnc]

hello everybody,

I'm looking for an used catamaran, and the boats I find have old motors, usualy 2000 to 3000 hours . I do not know anything about diesel motors and I want to know how many hours a 20 to 30 hp diesel lasts before having big problems to fix??
If anybody can share his experience and tell me how much hours such a motor can last, I would be pleased and more confident.

thanks
Robert

[Steve Pope]

The GM 71 series was built around a 5000 hour life span between overhauls. That being said diesels have come a long way since then, the maintenance schedule and actual useage probably has more input into motor longevity than actual hours. Often marine diesels suffer from lack of use rather than over use. Diesels thrive on being used under load and suffer from light duties ie. Battery charging.

[JamesFrance]

Yes I would agree with Steve entirely. I used to be in what in the UK is called the Plant Hire business. I expected a small compressor engine to go 10 years before needing any attention and they were on tickover a lot of the time and frequently missed their maintenance schedule, as the long term hirers moved them around a lot, so we couldn't find them.

If they have regular oil and filter changes the hours will not be the important factor. The marine environment is much more likely to be the cause of any problems.

[Boracay]

When I brought Boracay there were five indicators that the engine was kaput.

They were :-
1) Engine was old (25+ years)
2) Engine was hard to start
3) Engine had clearly done a lot of hours
4) There was evidence of corrosion and poor repairs
5) There was oil everywhere

Together they told me that the engine was gone.

I was stupid enough to believe several mechanics and a surveyor that the engine was good and wasted a considerable amount of time, money and effort trying to get it to work.

I still find it hard to believe that qualified and experienced persons could get something so basic so wrong.

[cooper]

I think that boracays 5 points are spot on.....I have an engine that matches that description and it is "fit only to be an anchor" as a wise old mechanic once told me. Unfortunately it is to old to rebuild. Engine hours are only a minor indicator of the engines condition. Well loved machines last well !!Perhaps a regular visitor to this forum who has posted some "internal " shots of an engine recently, may like to post them here ?