Diesel Engine hours....

[RonE]

At what point does a diesel, and in our case a universal, have to many hours.
I read that anything over 1500 hours on a marine diesel means that there should be an overall.
So I would think while searching for a used boat, one should not want to purchase a boat
that has more then say a 1000 hrs. So should one stay clear of a diesel that has 2500 or even
3500, I recently observed. Unless of course it has been noted an overall had been done.
Ron

[Craig Illman]

A compression test would be a better metric than just engine hours. I'd recommend spending the money on an engine survey that would include an oil analysis for both the engine and transmission.

Craig

[Stu Jackson]

The answers to your questions go like this:

1.  A well maintained engine that has more hours is better than a neglected one with less.

2.  Lugging a diesel engine is the worst thing that can be done with or to it.  Running the engine without letting it warm up fully by just motoring out the marina and setting sail is worse than running it at operating temperature all day.

3.  For recreational boats in temperate climes, anywhere from 100 to 150/+ hours per year is a fairly standard norm.  You do the math on the age of the boat.  When we bought our then-12 year old boat, it had 888 engine hours.  It now has almost 2600 (total, not more) in our 13 years of ownership.  Regular oil and filter changes.  It has NOT been rebuilt, nor do I see a need to do so.  Most of the engines on our boats have not been rebuilt.  If a boat you're looking at has significantly more than these, like your 3500 example, the boat could well have been used in charter.  Ask questions, 'cuz while charter boats may have more maintenance done on the engine (maybe!) the rest of the boat has most likely taken a lickin'.

4.  The appearance of the engine and the engine compartment will go a long way to understanding what you're looking at.  See my post in one of your previous topics.

5.  Regular hose replacements are necessary.  If the hoses are still painted on the boats from the 1990s, look very carefully.

6.  Maintenance records should be available, and should be gleefully presented to you.  Lack of records doesn't mean that work hasn't been done, but if available are a good indicator of the care someone has taken with the engine, and most likely the rest of the boat.  I keep records 'cuz I can't always remember what I did yesterday, and records can keep track of important operational trends.  Very valuable information.

[Ron Hill]

Ron : I agree with what Stu and Craig have said.
 
What you have to remember is that the older (20 years and over) boats engines are going to get near the life age of the seals inside the engine.
You can check compression, but the seals are always in question.

As long as you realize that and the fact that the engine is only a part of a C34, it can be replaced just like other parts - expensive but replaceable!!   A few thoughts