Inboard diesel hours life expectancy

[myusernam]

Assuming servicings have been done, how many hours before say 150hp vovlos are shagged? I.e. what is a reasonable service life - 3000 hours - 6000? Once old can you rebuild or is it more cost effective to just replace? Most boats this vintage seem to replace engines rather than rebuild..Is there a reason for that? (cost i guesss) Also Volvos are very expensive parts aren't they?

[Noelm]

I guess like all boat motors, it could go for twice that long, but salt water years are salt water years, rust/corrosion will probably kill it long before it wears out.

[Midnight]

Yep, what Noel said. Marine age and lack of use is what kills most of them.

Volvo parts are expensive, for sure, but they do make nice engines. Getting one that has been used regularly, not over propped, serviced as per the books or better is the key to a long and happy marriage with a marine diesel.

My V8 Cats have 26 years and over 5000hrs on them, and I fully expect another 5000 out of them yet.

If you can be a little more specific with the engine model and application, you will get a better answer.

Cheers,
Myles

[mal555]

I think most/any marine diesel parts will be expensive.

Every application will differ depending on how the engines have been maintained.

As Myles suggests, perhaps be more specific on the model/year?

Generally though many folks like new technology regarding anything they buy or repower, unless they have confidence in their own ability to keep the older engines running reliably.

[bluefin59]

I know a charter boat owner with twin yamnar turbo diesels and dropped one after it had done just on 1000 hrs and it would have cost a bomb to reco so ended up putting a new one in that cost 50K ,it suffered from salt water ingestion through the intake manifold and these motors where both checked by a marine mechanic and oil samples taken before boat purchase...Matt

[Midnight]

Bluefin, was it an after cooler failure that caused the saltwater ingestion, or poor installation? Yanmars are a good thing when set up and maintained right.
I have a mate with 5500+ hours on a 440hp Yanmar, and it is going like a beauty, with very little blowby or oil consumption.

Cheers,
Myles

[myusernam]

I know a charter boat owner with twin yamnar turbo diesels and dropped one after it had done just on 1000 hrs and it would have cost a bomb to reco so ended up putting a new one in that cost 50K ,it suffered from salt water ingestion through the intake manifold and these motors where both checked by a marine mechanic and oil samples taken before boat purchase...Matt

how the fark can one diesel cost that much. you could buy a truck, throw away the car part and put the diesel in there.! rediculous.

My old boy marinised a chinese diesel himself - he made a heat exchanger out of some plate and some copper coil. Fiberglassed an aqua lift muffler out of a bin! But you can just bolt on a heat exchanger and cool the exhaust. I dont get it...

[chris69]

Anything volvo is expensive,if its an older motor you should get good life if maintained,it depends apon how it was driven realy and what rev range its been operating at and weither there are any stress fractures and fatige in the head and weither the seals are ok in the linners, all the sevices in the world dont tell you weither the head is stuffed other than loss of water in the header tank if its got one,oil sampleing will only give you metal samples to determine what is wareing and at what rate the ware is happening over a time of doing S.O.S

Haveing a compression test would be the best thing to tell you were the motor is at and how much life is left diesels can run for many thousands of hours.

Gee matt 1000 hours is not much even for a yanmar something wrong there as Midnight said his CATS are old but there good old stock and have allways been a good thing other then the Kmart cats and he could get more than 10,000 hours,ive seen 20,000 to 26,000 hours on diesels in trawlers, trucks can go 1,000,000 miles before a rebuild but only because they dont cool down like taxies.

[mal555]

Yanmars are a good thing when set up and maintained right

I remember a number of years ago a major Queensland power cat manufacturer claiming they would never again install a Yanmar engine due to serious mechanical problems customers had
experienced within a few hundred hours of operation, quickly shifting the blame from what was clearly installation issues, back to the engine design.

I noticed in the latest Maritimo/Mustang blurb they are boasting (as a first in Oz) a complete Volvo factory endorsed installation check-off on each of their new vessels with IPS.
This company are trying to establish an export market into Europe where CE certification is standard on any vessel built or imported.

There could be something in this other local manufacturers could learn from?

[myusernam]

off topic but yanmars are toyotas aren't they? Why cant I just get a rebuilt or wrecked car turbo 6cyl out of a cruiser ute and bolt on a heat exchanger and gearbox. throw a few anodes in some welch plug holes. get the exhaust shop to make a mandrel bent stanless exhaust to suit the boat and have a belt run jabsco cooling the exhaust? What horsepower do they run at? Be around the 200hp?

[bluefin59]

Yeah way expensive but that was a brand new motor complete fitted from yamnar as a rebuild on the old motor was going to take weeks and parts had to be imported to do the job . But having said that the guy had only just bought the boat and it is his lively hood ,but now he is up to 3500 hrs on the old motor and 2500 on the new motor, the intake manifold was unbeknown to him sucking salt air which destroyed the turbo which dropped bots all through the engine, it was way ugly. And as far as cost goes I can't understand the price of outboards , look at the price of say a 140hp motor all upward of 16 k and a 300hp I guess would be over 35k , bloody rediculious ..Matt

[bluefin59]

Also it was a turbo diesel motor and the destroyed motor has now been rebuilt with overseas parts and put together by a catapiller mechanic . That's part of the problem that charter customers don't see it looks like a dream job but over the years I haven't met one that's wealthy from owning just a charter business , too many hidden costs and too much crap weather ...Matt

[chris69]

off topic but yanmars are toyotas aren't they? Why cant I just get a rebuilt or wrecked car turbo 6cyl out of a cruiser ute and bolt on a heat exchanger and gearbox. throw a few anodes in some welch plug holes. get the exhaust shop to make a mandrel bent stanless exhaust to suit the boat and have a belt run jabsco cooling the exhaust? What horsepower do they run at? Be around the 200hp?

Car diesels are not marine diesels different bore and stroke to achive the hp and toruqe at a lower revs.

[chris69]

Yeah way expensive but that was a brand new motor complete fitted from yamnar as a rebuild on the old motor was going to take weeks and parts had to be imported to do the job . But having said that the guy had only just bought the boat and it is his lively hood ,but now he is up to 3500 hrs on the old motor and 2500 on the new motor, the intake manifold was unbeknown to him sucking salt air which destroyed the turbo which dropped bots all through the engine, it was way ugly. And as far as cost goes I can't understand the price of outboards , look at the price of say a 140hp motor all upward of 16 k and a 300hp I guess would be over 35k , bloody rediculious ..Matt

Hi Matt did the yanmar have a intercooler on it!

[bluefin59]

Not sure Chris i could make a call and find out but it's not important now but maybe someone here that has a black watch with twin yamnar would be able to comment ? Are you going to be on the water by summer Chris ..Matt