How many hours can an engine last ?

[Dockhead]

Originally Posted by 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

That's a Perkins 4-108.



I got more than 20,000 hours out of one of those used as a propulsion engine. Was still going strong when we sold the 40-year old boat for a good price -- the buyer was not concerned about the engine hours.



If you have sea water in the coolant you have a perforated heat exchanger. That's no reason, by itself, to replace the engine. Did you by chance forget to change the zinc?


I guess it's too late if you already took it apart.

[Emmalina]

I'm at about 16000 hours but the old 78 Perkins were made to last with cast iron etc etc. Modern engines like everything else are built to last tot hours. I do carry a full rebuild kit which cost 500usd . The beauty of the tractor world is when talking spares as apposed to the word marine being thrown in. I expect this engine will outlast me.

[skipperpete]

Originally Posted by 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.

The MD22 is the devil you think you know, generally they last quite well but when they fail, they fail expensively. The obvious most destructive event is a timing belt breakage or the associated idler and adjuster, then there’s the aluminium cylinder head, it suffers from warping and gasket failure if the engine has an overheat and is a difficult head to surface grind because of those steel precombustion chambers. Then there’s the raw water pump, less of a problem on the Volvo’s that had the belt driven one but notorious for tang failures on the models directly driving the pump with the end of the camshaft, another silent failure waiting to happen. The injectors are inclined to leak combustion pressure but unlike most other engines, the MD22 handles this rather badly because, A. The spring loaded hold down clamp doesn’t permit more tightening and B. The combustion gas tracks into the aluminium head and often too deeply to repair with a seat cutter so that the head becomes unusable. Then there’s the valve clearances, Perkins just assumed that valves would never wear up into the seats so the adjustment would only rarely need to be done…. This process requires a special tool to hold down the camshaft, other tools to hold the injection pump and crankshaft, and a selection of cam buttons to adjust the clearances.

[skipperpete]

Originally Posted by Dockhead

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.

Lugger used Komatsu, Deere and Toyota base engines (and probably others that I don’t have knowledge of) but differed from Betamarine , Lehman, Nanni and the rest of the herd that simply bolted a heat exchanger and a raw water pump to an off the shelf engine by being possibly the only company to buy the industrial core engines and replace internal parts that were known to be problematic. This was akin to what was once called “blueprinting” ie getting the fits , tolerances and weights correct to the drafted blueprint design, not to the machinist limitation tolerances of “plus or minus” .005”. With the manufacturing process it was possible to get a .005” undersize piston in a .005” oversize cylinder and this randomness of permitted error appeared throughout the whole engine. The errors occurred because the machine tools that were used to make the engines weren’t totally accurate unlike the machine tools of today that relentlessly maintain Zero tolerance on all moving parts. Lugger didn’t blueprint entire engines, just the bits they thought mattered . The Komatsu engines were modified to put out over 700hp from the base engine 600hp with better pistons , rings, turbo’s ,manifolds, heat exchangers and coolers and they ran flawlessly in fishing vessels and gensets. I saw a Lugger promo movie with the John Deere modifications where the same procedure was carried out and all the old stuff returned to Deere for re use and when Deere eventually marinised their own engines they were way cheaper than the Lugger Deeres. Deere was then using latest generation tooling so the service life increased from “ very good” to really excellent but they adopted electronic injection to stay in the EPA regs and declined a little in reliability ( fishermen don’t want an engine they can’t get fixed at sea)
Yes, I consider Lugger engines to be unique and would expect over 20,000 hrs of hard work before a rebuild.

[CMH]

Originally Posted by Dockhead

That's a Perkins 4-108.



I got more than 20,000 hours out of one of those used as a propulsion engine. Was still going strong when we sold the 40-year old boat for a good price -- the buyer was not concerned about the engine hours.



If you have sea water in the coolant you have a perforated heat exchanger. That's no reason, by itself, to replace the engine. Did you by chance forget to change the zinc?


I guess it's too late if you already took it apart.

Dockhead, the engine half of the Westerbeke W58, 20 KW is a 40 hp, Mazda E3000 engine, at 154.2 CI.
You are correct in that the heat exchanger was the latest issue and it was possible to repair/replace. However, I’ve been working on that 40 year old generator for two solid years now and I had reached my limit (hoses, water pump, wiring, exhaust manifold, wiring, fuel pump, wiring) So out with old and in with a spanking new 11 kw Kohler in a neat white package half the size of the old one. To say I’m excited about having dependable power in a package half the size would be a massive understatement.

[SailingHarmonie]

Originally Posted by skipperpete

The MD22 is the devil you think you know, generally they last quite well but when they fail, they fail expensively. The obvious most destructive event is a timing belt breakage or the associated idler and adjuster, then there’s the aluminium cylinder head, it suffers from warping and gasket failure if the engine has an overheat and is a difficult head to surface grind because of those steel precombustion chambers. Then there’s the raw water pump, less of a problem on the Volvo’s that had the belt driven one but notorious for tang failures on the models directly driving the pump with the end of the camshaft, another silent failure waiting to happen. The injectors are inclined to leak combustion pressure but unlike most other engines, the MD22 handles this rather badly because, A. The spring loaded hold down clamp doesn’t permit more tightening and B. The combustion gas tracks into the aluminium head and often too deeply to repair with a seat cutter so that the head becomes unusable. Then there’s the valve clearances, Perkins just assumed that valves would never wear up into the seats so the adjustment would only rarely need to be done…. This process requires a special tool to hold down the camshaft, other tools to hold the injection pump and crankshaft, and a selection of cam buttons to adjust the clearances.

I think you would actually find I know all those issues quite well, and that is why I have a TMD22 that continues to live a happy life will most have been junked. Most people run things until they break, then try to get them fixed. I prefer to take care of my expensive toys.

Like any engine with a timing belt, it needs to be changed (along with the idler) as per the maintenance schedule. If it is not changed, of course it fails, turning the engine to junk. It also needs its tension checked and adjusted periodically.

The water pump tang issue doesn’t happen IF you know how to align it properly. I just pulled out the water pump after 1000 hours, and the tang looks like new because I have the tool to align it as it needs to be.

Taking care of the water pump, and having a temperature alarm on the water cooled part of the exhaust elbow make overheating very unlikely.

Yes, adjusting the valve clearances it a pain, but it’s not impossible, and it needs to be done. So I do it.

So I agree with you. If you ignore a diesel’s needs it will die an early death, and leave you in the lurch. If you take care of it, it just works, and works.

[Dockhead]

Originally Posted by CMH

Dockhead, the engine half of the Westerbeke W58, 20 KW is a 40 hp, Mazda E3000 engine, at 154.2 CI.
You are correct in that the heat exchanger was the latest issue and it was possible to repair/replace. However, I’ve been working on that 40 year old generator for two solid years now and I had reached my limit (hoses, water pump, wiring, exhaust manifold, wiring, fuel pump, wiring) So out with old and in with a spanking new 11 kw Kohler in a neat white package half the size of the old one. To say I’m excited about having dependable power in a package half the size would be a massive understatement.

Oh, I stand corrected. I never saw a Westerbeke genny with anything other than a Perkins engine.


Wish you enjoyment with the Kohler. I have a 6.5kW Kohler generator which was part of the original build of my boat in 2001. It's based on a 1000cc Yanmar three cylinder tractor engine and runs at 1500 RPM. Dead simple and has been, touch teak, dead reliable all these years, not a lick of trouble with it which didn't result from my own errors of maintenance or operation. Hope you get as good service from yours as I have out of mine.


Mine is double-derated -- first of all, at 230v, it produces 6.5kW vs 8.0kW in the 110v version (because to get 50hz, it runs at 1500RPM instead of 1800RPM). Then, I derate it to 25 amps from 29 using the power control in my Victron charger/inverter. Then, I try never to run it with less than a couple kW of load. That's, for whatever it may be worth.

[Wotname]

..........
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.

This ^^^ plus starts well when cold.

........

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.

The jury is still out regarding turbos in a sailing boat. Yes, they are ideal when the engine has been matched to the expected use of the boat but all too often, they are fitted to boats that cannot use the power range where the turbo is active. In that instance, the turbo is the very devil. Unless the operator is diligent in operating the engine in the turbo rpm range often enough, the turbo becomes an expensive regular replacement option.

An acquaintance bought a older boat which was advertised with a near new (500 hour) 75 hp turbo engine. The turbo failed shorty after purchase and it was then he found out this was the second time the turbo had failed; so 2 failed turbos in less than 600 hours. Of course it was operator error but as the boat only needed about 40 hp 95% of the time, the 75 hp turbo was overkill and doomed to fail. He did not get it replaced, he got it removed and is now happy with the 55hp that remained.

[Dockhead]

Originally Posted by Wotname

. . . The jury is still out regarding turbos in a sailing boat. Yes, they are ideal when the engine has been matched to the expected use of the boat but all too often, they are fitted to boats that cannot use the power range where the turbo is active. In that instance, the turbo is the very devil. Unless the operator is diligent in operating the engine in the turbo rpm range often enough, the turbo becomes an expensive regular replacement option.

An acquaintance bought a older boat which was advertised with a near new (500 hour) 75 hp turbo engine. The turbo failed shorty after purchase and it was then he found out this was the second time the turbo had failed; so 2 failed turbos in less than 600 hours. Of course it was operator error but as the boat only needed about 40 hp 95% of the time, the 75 hp turbo was overkill and doomed to fail. He did not get it replaced, he got it removed and is now happy with the 55hp that remained.

There are many benefits to turbos on diesel engines, but the key one here is that the displacement of the engine can be better matched to the average power needed at normal cruise speed. Overpressure from the turbo is then used to get your maximum power needed in unusual situations.

This results in higher cylinder temperatures at normal cruise speed, which is very beneficial. It also allows the engine to be smaller and lighter -- a big plus in a sailboat.

In the case you cited, more than 50% of maximum power (40hp output from a 75hp engine), the turbo should have been working and there should be no problem at all. Using even 20% or 30% of max for long periods of time is normal operation for a turbo diesel engine, so there must have been some different problem.

Yanmar require you to use high power every two hours, if you are operating at less than 2000 RPM (on its 3800 RPM redlined turbo diesels like mine). This burns off carbon deposits and spins up the turbo to prevent hard carbon deposits from forming in the bearings. I do this religiously with my 4JH3 HTE (100 hp, 2000cc turbodiesel), and have never had the slightest problem with the turbo in 15 years and 4200 hours of use. I often operate for hours at a time at 1500 RPM or even less, when motorsailing. I know a lot of people with the 4JH3 and 4JH2 turbodiesels and never heard of anyone having a problem with the turbo. I would suspect a problem with oil or coolant supply in your friend's case.

Another thing that can kill turbos is shutting them down without idling for a while to let the turbo cool down. When you shut the engine down, oil supply is cut off, and the hot exhaust turbine can heat soak the bearings, coking them by cooking the oil remaining in them. So there's that. Easy to avoid.

Other benefits of turbodiesels are less mechanical stress inside the engine at high power outputs, because of much less pressure delta between intake and exhaust. This makes turbo engines much smoother. The exhaust turbine smooths out and dampens pulses in the exhaust gas stream, making turbodiesels much quieter. Yet another benefit is that, despite the intercooler, the charge air is still much warmer than in naturally aspirated diesel. This is one more help for keeping cylinder temperatures up. Low cylinder temperature wreaks havoc in a diesel engine, causing wet stacking, premature bore wear/bore polishing, fuel contamination of the oil, etc. Turbodiesels are much less susceptible to this than naturally aspirated diesels, which pump stone-cold air straight into the cylinders.

Turbochargers on diesels don't have wastegates, so they are supremely simple devices with only one moving part. They are not even very expensive, on the odd chance that you someday have to replace one. The advantages are so great that you can no longer even buy a diesel engine for a car or truck without a turbocharger. I wouldn't have common rail on a boat (different conversation), but I wouldn't have a boat engine in a sailboat without a turbocharger, personally.

[Wotname]

^^ Thanks for the detail about turbos.

FWIW, in the failed turbos of the PO of my friend's boat, I am sure it was operator error. I probably wasn't clear enough in my description when I said 'but as the boat only needed about 40 hp 95% of the time'; a better description would be 'but as the boat only ever needed a maximum of about 40 hp 95% of the time' i.e. it was operated at much lower hp levels much of the time. The Volvo dealer suggested the best fix was to remove the turbo which reduced the hp from 75 to 55. Interestingly the turbo did contain a waste gate which was also frozen.

[rslifkin]

A stuck wastegate definitely makes me think it literally never got run hard. Any turbo with a wastegate should be occasionally pushed hard enough that the wastegate will actually open to limit boost. Otherwise they're likely to soot up and stick closed (with resulting over-boost if you do go to WOT at some point).

In general, turbos are good and turbodiesels tend to be more efficient. But some turbocharged engines are more prone to issues if chronically under-loaded (while others tolerate it well). So there are definitely downsides to significantly over-powering a full displacement hull.

[SailingHarmonie]

Originally Posted by Dockhead

Turbochargers on diesels don't have wastegates, so they are supremely simple devices with only one moving part.

I agree with everything you said about turbos and diesels except this.

Some diesel turbos DO most certainly have wastegates. A wastegate that is stuck closed will over pressure the cylinders, and that is all bad. A gate stuck open basically disables the turbo. But again, these are all really simple devices. The only engines I have seen with waste gate issues were poorly maintained, and the accumulated rust jammed the moving parts.

There is a good argument for adding a boost pressure gauge on any diesel equipped with this kind of turbo, just in case.

[Dockhead]

Originally Posted by SailingHarmonie

I agree with everything you said about turbos and diesels except this.

Some diesel turbos DO most certainly have wastegates. A wastegate that is stuck closed will over pressure the cylinders, and that is all bad. A gate stuck open basically disables the turbo. But again, these are all really simple devices. The only engines I have seen with waste gate issues were poorly maintained, and the accumulated rust jammed the moving parts.

There is a good argument for adding a boost pressure gauge on any diesel equipped with this kind of turbo, just in case.

I stand corrected!

A good reminder that "I never saw one" does NOT equal "it does not exist".

Thanks!

[Goodxcharly]

Run!!!! From that deal! The hours are up there though I would run from the saildrive.
If you really like the boat I would factor in replacement cost for the engine and saildrive. After saying that I still wouldn’t own a sail drive.

[Nicholson58]

Our 1984 Westerbeke engines run like new, instant start, no faults.
115 HP six cylinder main & 75 HP four cylinder 12.5 kw generator

Clean fuel and clean oil are king to long life. I have a one micron fuel polisher feeding the Racor filters of both engines. Also, each engine has a crank case one micron bypass filter polisher.

The class 8 over the road tractors today are using centrifugal oil cleaners. They are far better and easier to maintain than my bypass cleaners. No elements to replace. Proven results say extremely long life results with ultra clean oil. Ultra clean fuel will never fault your injectors or high pressure injector pump.

It’s never too late to add these features to your diesels.