How many hours can an engine last ?

[Dockhead]

Originally Posted by skipperpete

Lugger engines are fairly unique and they can rightfully claim 20,000 hrs, it helps that they rarely have a wet exhaust and are often keel cooled . The biggest single cause of failure with yacht engines that die young is the wet exhaust or heat exchanger problems.

There's nothing really unique about Lugger engines, which are just very well marinized John Deere tractor engines, if I'm not mistaken.

It's not unusual for small diesel engines to go 20,000 hours. We had a Perkins 4-108 on our last boat which hit 20,000 hours about 10 years before we sold the boat (the engine hours clock broke at that point). We never had the slightest problem with that engine other than profuse oil leaks; never even had the head off it.

But you can't count on that. The risks of failure increase gradually as the hours build up, and suddenly in case of some trauma.

I have 4,200 hours on my Yanmar 4JH3 HTE. It had 830 hours on it when I bought it in 2009. It has smoked since the day I bought it but otherwise has been bulletproof. I expect to get a few thousand hours more out of it.

[Orion Jim]

How long is a piece of string?

[Dockhead]

Originally Posted by Orion Jim

How long is a piece of string?

It's worth mentioning that most sailboat engines don't die of old age.


They usually die due to an incident like overheating, backflow of sea water into the exhaust ports, low oil pressure incident, etc.


So if you've owned the engine since new and you know for sure that there were no lapses in maintenance and no such incidents, then you can be pretty confident of getting a lot of hours out of it.


If you're buying it used with 6,000 hours, it's pretty much a cat in a bag.

[LeaseOnLife]

Originally Posted by Dockhead

, it's pretty much a cat in a bag.

Schrödinger comes to mind

[MicHughV]

Things that go bang in the night

"hope it works like it's supposed to"
"seems to run ok"
"only smokes a little bit"
"grinding noise goes away after a few minutes"
" doesn't leak much"
"only use one quart of oil per week"
"only hard to start when cold"
"funny sound goes away after 10 minutes"
"alarm always goes off after 15 minutes"
"I can live with the vibration"
"belt just needs tightening"

etc, ad infinitum

[Dockhead]

Originally Posted by MicHughV

Things that go bang in the night

"hope it works like it's supposed to"
"seems to run ok"
"only smokes a little bit"
"grinding noise goes away after a few minutes"
" doesn't leak much"
"only use one quart of oil per week"
"only hard to start when cold"
"funny sound goes away after 10 minutes"
"alarm always goes off after 15 minutes"
"I can live with the vibration"
"belt just needs tightening"

etc, ad infinitum

Not all of these are of the same importance.



A little smoking is usually no big deal; likewise a little leaking (otherwise no Perkins would be considered a usable engine).


But funny sounds and grinding sounds and hard starting are time to repower.


How a diesel starts is a key characteristic; different from spark-ignition engines. A diesel that starts well, has good oil pressure, doesn't make any funny sounds, doesn't burn oil, is very likely to be a perfectly good motor, even if it smokes or leaks a bit.

[rslifkin]

In general, the more hours it has, the more of a careful look I'd want to give the engine. At 6000 hours, I'd be looking through whatever maintenance records there are, carefully assessing every component that can be readily inspected (like exhaust elbows), and I'd want a compression test.

Realistically, if all indications point to good maintenance and it checks out healthy (good compression, good oil pressure at hot idle, runs well, etc.), there's no reason to believe that it won't run another few thousand hours.

There's not really a set lifetime for an engine, it depends mostly on the maintenance it's received, how it was operated, etc. You can easily end up with an engine in poor condition after 2000 hours and another with 6000 that's still healthy and will run to 10,000+ if good maintenance and reasonable operating practices are continued.

[Dockhead]

Originally Posted by rslifkin

. . . There's not really a set lifetime for an engine, it depends mostly on the maintenance it's received, how it was operated, etc. You can easily end up with an engine in poor condition after 2000 hours and another with 6000 that's still healthy and will run to 10,000+ if good maintenance and reasonable operating practices are continued.

This

I would add to this the value of using a mechanic's stethoscope, and infrared thermometer.

Any bearing sounds or piston slap is a deal breaker in my view. Tappets should sound normal. There should be no sounds from pumps or camshaft drive systems. Injection system should make consistent sounds.

If the engine has a turbocharger (as all good diesels do), you will want to run the engine up to redline under load and hold it there for a while, listen to the turbo to be sure no sounds of bad bearings, then listen to it again when it spools down when the engine is brought back to idle. Check with infrared thermometer that there are no major hot spots. It's good to check the intake tract for oil getting past turbo seals.


Don't worry excessively about the turbo, however. These are extremely reliable and not all that expensive to fix or replace if something happens.

[MicHughV]

My point really is that buying a boat with 6,000 hours on the engine means that comes time to sell it, it may have have 8,000-10,000 hours on it.
Whether the engine still runs good at these hours is kinda moot, as any prospective future buyer is likely to balk at such high hours, knowing that a rebuild or replacement is likely in the near future. This being the case, a prospective future buyer is likely to try and negotiate a substantial discount.
This being case, why not have the pleasure of having a new engine yourself and then selling a boat with reasonable low engine hours on it.

The OP didn't state the year of the boat, so don't know if these hours were accumulated over 10 years or 1 year.
Was the boat in charter ever ? This info will also go a long way in determining the many hours and probable maintenance, etc.

Quite a few unknowns to really make a stab at predicting what's next, but if it were me, I'd be considering a substantial reduction in price or moving on.

The price reduction is also iffy, as the seller may have figured this into the asking price, and jacked up the ask price, knowing the engine issue is likely to arise.

Tough call, but 6,000 hours speaks volumes.

[NorthCoastJoe]

Not knowing the engine history nobody can realistically say.

Do one of these: https://www.partsvu.com/blackstone-l...YaAhFREALw_wcB

But there is no way to really know. I have a brand new Beta 50 now. From hours zero I know its history. That engine I expect to outlive my use of the boat. I keep detailed records and do an oil test yearly. So if you were looking to buy that boat I feel like my records would be useful. The Perkins 4108 I pulled had a little over 3000 hours on it when it ranaway, and the previous owner had poor records.

Up thread somebody who has been sleeping for 10 years said a 55 HP for $ 10-15,000. That price point is long gone. Just the engine alone will be more that, plus all the extras, hose, fittings, bolts and who knows what else you will find needs replacing when you open the can of worms. Add to that labor, haul out, lifting the engine out and dropping the new one in expenses.

I did all of this one year ago, repowering doing all the work myself and it still was expensive. My wallet still feels the pain.

[more]

Originally Posted by henris

Hello,


I am planning to buy a sailboat with a volvo-penta 55HP engine with a saildrive. The motor is running fine and was apparently well maintained. But... it has more than 6000h.
Should I consider it is at its end ?
What is a reasonable amount of hour to consider the replacement of the motor ?
What are the alternatives ?

16000 to 18000

[more]

Originally Posted by MicHughV

My point really is that buying a boat with 6,000 hours on the engine means that comes time to sell it, it may have have 8,000-10,000 hours on it.
Whether the engine still runs good at these hours is kinda moot, as any prospective future buyer is likely to balk at such high hours, knowing that a rebuild or replacement is likely in the near future. This being the case, a prospective future buyer is likely to try and negotiate a substantial discount.
This being case, why not have the pleasure of having a new engine yourself and then selling a boat with reasonable low engine hours on it.

The OP didn't state the year of the boat, so don't know if these hours were accumulated over 10 years or 1 year.
Was the boat in charter ever ? This info will also go a long way in determining the many hours and probable maintenance, etc.

Quite a few unknowns to really make a stab at predicting what's next, but if it were me, I'd be considering a substantial reduction in price or moving on.

The price reduction is also iffy, as the seller may have figured this into the asking price, and jacked up the ask price, knowing the engine issue is likely to arise.

Tough call, but 6,000 hours speaks volumes.

what you sell boat becouse 3-4000€ new engine block to expensive. now is perkins action to factory rebulid block for serie 100 to 400. this is volvo penta engine https://bu-power.com/en/service-and-...ement-engines/

[CMH]

Just today I finished removing a 40 year old 20 KW Westerbeke 40 hp diesel generator from my boat piece by piece. It took two guys three days. I was surprised that the cylinders looked practically new. It had 7,645 hours on it and was still running fine. Reason for removal: cooling system.was trash. - the engine coolant was mixing with sea water. ( and boy was it ugly).
Chris

[MicHughV]

Well, I have had my share of engine removal and replacement,,,,on my own boat and others.
It's an expensive and arduous task, no two ways about it. So much so, that one begins to look for excuses not to do it.
A savvy buyer will know what to look for and where, but a newbie, not so much.

There in lies the problem. People " hope" and " wish" for a certain problem to go away, and while some will apply a band aid fix, invariably the writing is on the wall.
Besides the $$ expense, it's also a lengthy time away from cruising, which further complicates the matter.

It's no easy decision, and one must remain unemotional about the matter and weigh possible options from several perspectives.

Without knowing all the facts of the matter, I'd be considering an engine swap, with all that entails, as likely the most prudent option.

[SailingHarmonie]

I am one of the odd balls, not scared of a high hour engine that has been well cared for.

Current boat has a 28 year old TMD22. It was always well maintained by two knowledgable previous owners. I bought her 7 years ago with ~7500 hours. She still runs like a top with 9950. There are no unusual maintenance costs, just the routine stuff. Burns no oil, hasn't lost any measurable performance. Drives the boat at the same speed with the same prop as she did when new.

The only unscheduled repairs in the last 4 years were one bad relay, and a leaking seal on the injection pump.

One of the key things is she gets used. 300 to 500 hours a year every year, year round. Diesels do not do well as couch potatoes, any more than people do.

Some day she'll blow a main crank seal, or something else fatal. But when I look at my friends and customers who have repowered, it is very unusual that it goes smoothly. I much prefer the devil I know.