High engine hours
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psneeld
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Mischief Managed
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Those boats typically have those great little 75HP Yanmar engines that only weigh 500 lbs and don't cost a lot of money. While I don't think 3700 hours is too much at all if they run right, consider the worst case scenario, new engines would not be a big deal since they are small and inexpensive.
backinblue
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Inexpensive relative to all boating expenses.
GoneDiving
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markpj23
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I'd not be worried about these - get an oil analysis done to be sure.
backinblue
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Ask to see service records. 3700 is not too much if well-maintained, but it's more than just oil changes.
SteveK
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3700 hrs on a 19 year old is 194 hrs average. Oil change records should show at least annual oil changes unless oil tests deferred.
A quick search suggests an expected life of 8000 hours. So it is at half predicted life, certainly not a high hour engine. IMO
A quick search suggests an expected life of 8000 hours. So it is at half predicted life, certainly not a high hour engine. IMO
backinblue
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Yanmar recommends much more thorough maintenance at 1000 hour intervals. You should be able to find an engine manual and see if they generally kept up with the recommended maintence schedule.
Irish Rambler
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I have no experience with Yanmar engines but we have Scania's, Mercedes and Iveco trucks with up to a million miles on them. Once they are sold they go to the African and Asian continent where they go on to continue a working life.
Hippocampus
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That’s a very common sailboat engine. Have had several Yanmars in different sizes. Personally think it’s a much better engine than the comparable sized Volvo. Service and parts should be available anywhere in the world and often aren’t as dear as other brands. Make sure turbo service was done and check boost. Heat exchanger and mixing elbow are other common neglected points. The tach is a another failure point. Usually just wiring but sometimes needs a rebuild. Have used Lauderdale Speed with good response. Mail it to them and get it back in about a week. We had Hinckley fabricate a stainless mixing elbow which was worthwhile. Been very happy with 3 and 4 yanmars. Think 10k hours about right. On sailboats operators run them at a small fraction of peak load and don’t go to WOT periodically as manual recommends. But in your prospective vessel would think that’s less likely.
High Wire
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firehoser75
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Maintenance is the key. If the engines have been well maintained in all regards, they are probably at about the halfway point (give or take a bit). This means, that if you continue with good maintenance (assuming they have been so far), and averaging 200 hours per year, you could see another 17.5 years of use before replacement/ overhaul. A friend has over 10,000 hours on his 2001 Cummins 6BTA and still going strong, but he has faithfully maintained this engine as the original owner.
Also realize that these are generalizations and may or may not be applicable to this particular engine, and many factors like how it was run or worked can come into play.
Good luck.
Also realize that these are generalizations and may or may not be applicable to this particular engine, and many factors like how it was run or worked can come into play.
Good luck.
hmason
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Engine hours are very deceptive. If you make a 5nm trip at 5 knots it will log 1 hour on the meter. If you make the same trip at 10 knots you will only add 30 minutes to the meter. If a boat is run hard all the time it will show lower hours than a boat that was run at moderate speeds. Which boat would you prefer? The real measure is gallons of fuel burned. Just sayin'
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GoneDiving
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So am I at 50 odd years old?
GoneDiving
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I've never crunched the numbers. Mains went in (probably used) in '73. 25 years commercial work and then private pleasure boat there after.
Apologies for the thread drift
SteveK
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A very true analogy. The hour meter on my new to me boat had not worked in years. Logs however used the other hour meter to keep track for the broken one.
Now you got me thinking. Does an engine wear out sooner if run harder and thus at a lower engine hour? Maybe.
But I would guess that an operator always abusing an engine will leave telltale signs of maintenance or more likely the lack of maintenance.
rslifkin
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Generally, yes, an engine worked harder will wear out sooner than the same engine worked more lightly (provided the lightly worked one isn't being under-loaded to the point of causing issues or extra wear from running too cold). How significant the difference is will depend on the engine design in question.
firehoser75
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I agree completely with the fuel burned being a better measure of wear than strictly engine hours! After all, higher RPM uses more fuel for the same hours.
All things being equal (same engine, age, maintenance, etc.), the engine run at 1400 RPM will generally experience less wear than the same engine run the same hours at 2400 RPM.
For example, the engine run at 1400 rpm for 3500 hours will have 294,000,000 revolutions while the engine run at 2400 rpm for 3500 hours will have 504,000,000 revolutions. (A difference of 210,000,000 revolutions). For general wear and tear, it is obvious that the engine with more revolutions should have experienced more wear. This is obviously a simplification and does not factor in "other factors" like engine temp reaching the recommended level, etc.
However, for this discussion, as stated by myself and others, having 3500 hours on a 20 year old engine is not really high hours. The buyer would still be wise to have it checked completely by a recommended professional to better understand the actual condition of that engine.
Edit: The friend I mentioned in Post #18 who has over 10,000 hours on his Cummins 6BTA normally operates his engine at approx. 50% throttle which does not work the engine hard, but does work it enough to operate at the proper temperatures, etc.
All things being equal (same engine, age, maintenance, etc.), the engine run at 1400 RPM will generally experience less wear than the same engine run the same hours at 2400 RPM.
For example, the engine run at 1400 rpm for 3500 hours will have 294,000,000 revolutions while the engine run at 2400 rpm for 3500 hours will have 504,000,000 revolutions. (A difference of 210,000,000 revolutions). For general wear and tear, it is obvious that the engine with more revolutions should have experienced more wear. This is obviously a simplification and does not factor in "other factors" like engine temp reaching the recommended level, etc.
However, for this discussion, as stated by myself and others, having 3500 hours on a 20 year old engine is not really high hours. The buyer would still be wise to have it checked completely by a recommended professional to better understand the actual condition of that engine.
Edit: The friend I mentioned in Post #18 who has over 10,000 hours on his Cummins 6BTA normally operates his engine at approx. 50% throttle which does not work the engine hard, but does work it enough to operate at the proper temperatures, etc.
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backinblue
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Even if we all firmly agree that fuel burned is a better measure than engine hours, it's a moot point if there is no record of fuel consumption over the life of the boat, which I'm sure is 99+% of the cases. I get it, it's an easy concept to understand just like number of revolutions vs. hours, but why do we even discuss it if that data is not available?
backinblue
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OK I'm always willing to learn. My engine is circa 2012 and I am not aware of any such data. But even if it did, what would I comapre it to as a buyer? You don't see ads where boat A has consumed 10,000 gal of fuel and boat B has consumed 20,000 gal within the same engine hours. I guess for a particular boat, if you had both engine hours and fuel consumption you could make some assumptions, but still not really know. Maybe a boat is run very lightly 70% of the time, but 30% at WOT vs. a boat that is run 99% of the time at 50% load. They may have similar numbers, so what would that tell you?
firehoser75
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It probably is available in the more modern electronically controlled engines. However, even with the older engines, by asking questions of the current owner about boat operation, one can get a general idea of how "loaded" or how hard the engine was worked.
For example, using my friend's 10,000+ hour Cummins 6BTA, I also know of some other owners (planing boats) where they ran their 6BTA's hard, even overloaded at 2500 rpm (boat loaded so heavy as well as over propped) where they needed a rebuild at 3500 hours or sometimes less. Same engine, but how it was used (treated) being really important (assuming same maintenance).
I think discussing it here, including your point about the info not being easily found, is something that a lot of people don't think about, and it is worth considering as part of all the considerations when boat buying. JMHO.
For example, using my friend's 10,000+ hour Cummins 6BTA, I also know of some other owners (planing boats) where they ran their 6BTA's hard, even overloaded at 2500 rpm (boat loaded so heavy as well as over propped) where they needed a rebuild at 3500 hours or sometimes less. Same engine, but how it was used (treated) being really important (assuming same maintenance).
I think discussing it here, including your point about the info not being easily found, is something that a lot of people don't think about, and it is worth considering as part of all the considerations when boat buying. JMHO.
SteveK
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My car has an average speed digital readout. That must be revolution based.
Mate that with an hour meter? Maybe some computer science guy can develop an hour meter not based on just real time, but adjusted to run slower or faster outside the recommended engine rpm (which is regular time).
That sounds a lot like a speedometer with an odometer for boats
Mate that with an hour meter? Maybe some computer science guy can develop an hour meter not based on just real time, but adjusted to run slower or faster outside the recommended engine rpm (which is regular time).
That sounds a lot like a speedometer with an odometer for boats
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A friend with 1950s CATs, has hour meters that record revolutions turned rather than hours. at cruising speeds, 8 to 9 knots, they are close to clock hours. at fishing speed, not close at all, so his 15000 hrs run took a lot longer that that in real hours.
