Engines

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Obviously the life of an engine is fundamentally dependent on the maintenance and type of use it's had, but how many hours might one expect a modern(?) marine diesel to live. Specifically a TAMD63P, 6 years old with 600 hours - would the same engines with 250 hours, say 3 years old, be worth paying a substantial premium for (again assuming serviced in accordance with manufacturers recommendations etc)?
 
The 63p is a big heavy block slow revver. Owners will have likely cruised at 2300rpm because if pushed to the full 2700 fuel consum is much higher. We have a pair of 1999s, 350 hours. With proper maintenance, several thousand hours is easily possible. Remeebr 600 hours is like 25k miles in a truck where this engine is mainly used, and that's nuthin. So no massive premium for low hours imho. Premium if any will be much more influenced by condition of boat, lektronics, etc imho
 
I believe that the life of an engine is very heavily dependent indeed upon the use that it's had, so the hours of use ain't much of a guide, imho.

I overreved a petrol engine once, and it failed shortly afterwards. The "racing" of an engine or " "gunning" it means that automatic cars, for example, almost always have a longer life than manuals.

Is this engine in a boat? if so, the 600 will be seen as "older" of course with attendant other aging of the boat components. But those engines, as far as i kno, are comercially used diesels good for thousnads of hours, so probly best to buy the older one and let others worry themselves sick that they will realise the "advantage". Put another way, you can afford to splurge loads of tlc on the older one. Wuith the newer one, you'll be dead cheesed off if doesn't run super-smooth all the time. More info please.
 
I was talking to the guy that maintains my boat and he is currently working on a fishing boat engine that has just failed at 52,000hours and the fisherman was pissed off about it. Marine engines are often based on construction equipment engines many of which operate for many tens of thousands of hours without a major rebuild providing of course regular maintenance takes place
So the actual difference in condition between a 250hr engine and a 600hr engine is likely to be very little all other things being equal. The trouble is that the market perception is that the boat with the lower hours is worth more so there is a definite premium for the 250hr boat
But you're also comparing years as well, 3yrs v 6yrs old so there's a difference there as well. To pluck a figure out of the air, I would think that the premium for a 3yr old/250hr boat versus a 6 yr old/600hr boat of the same type and condition would be in the order of 15-20% but, personally, I would'nt have any problem buying the older boat because, as jfm has pointed out, the TAMD63P is one of Volvo's better engines; its been around for a few years and I'm not aware of any endemic problems with it
 
I had a chat with a Volvo engineer at the boat show a couple of years ago about exactly this subject
Engine age is important but his view was that the major problem with pleasure boat engines is lack of use and he advised buy an engine that had regular use rather than one that had been stood around and had low hours.
All advice I took was that 500 hours was minimal
 
I agree. Premature diesel engine failure is more often caused by lack of use rather than over use. Funny thing is that Petrols are actually better in this respect than diesels.



--
Tides - Never there when you need one.
Wind - Always there when you don't.

KevL
 
Is Cat any better?

I never asked about the Volvo 63P, but before buying a used boat with Cat 3116 (which are not that different) I spoke to a Cat technician - of course one who had nothing to see with the previous owner ;-).
He was totally convinced that if used properly those engines can achieve AT LEAST 10.000 hours.
I would expect Volvos to behave similarly.
 
Re: Is Cat any better?

If you have not been before have a look a www.yachtsurvey.com.
Very interesting site regarding "reliable"High performance diesels.As far as I can see from this website your 100hp 6 cylinder old dump truck lump used every day may last for years and years, but put a blower on it, then stick in a boat, use it maybe a dozen times a year and you will get a under a 1000 hours out of it if you are very careful/lucky before something will go pop and a very very expensive rebuild is needed.

Exercise is bunk.If you are healthy,you do not need it;if you are sick you should not take it.
 
Re: Is Cat any better?

Interesting site indeed.
OK, it shows that this David Pascoe is a surveyor: as such, its first job is worrying any boat entusiast enough to make him ask for a survey... And I must admit that I do not agree with his view on Italian boats - and Italy itself, to some extent - see reports of Cranchi 40 and Mochi 50.
By the way, those reports show also that his knowledge of this industry is not that deep: he is surprised that the Mochi is bad and the Cranchi is good. Of course, not knowing that Mochi went bankrupcy, being Cranchi the first European (not just Italian) builder in its segment, one can be surprised...
And generally speaking, I know lots of americans dreaming about coming to Italy, whilst the typical Italian who went to the US was just looking for a job, dreaming to come back ASAP. But that's another story, of course.
I just hope that he's too pessimistic about the diesels.
After all, they are piecese of modern american engineering, aren't they?
 
Re: Is Cat any better?

The coverage of diesel engine reliability and the addition costs of maintaining a diesel engine are well covered in the website and go some way to counter balance the myths about high performance diesel engines.Everyone assumes it would appear, that all diesels can be considered the same in reliabilty and length of time between overhauls and of course are better in boats vis a vis petrol engines.The main point of the argument is that if you leave out the "very important" matter of fuel cost,you may be worse off in your smallish boat with a diesel if you only use it very infrequently(as with 99% as most boats).The petrol could cost you less in initial purchase and maintaince .If you fancy a bit of maintaince I bet you could change a set of plugs and points and get some change out of £50.00,but how much is a set of injectors/fuel pump and of course you will have the skills and tools to set it all up..........

Exercise is bunk.If you are healthy,you do not need it;if you are sick you should not take it.
 
Re: Is Cat any better?

Well, I agree with your points. And with most of the points in that site actually.
Forgive my jokes on the author, mostly due to the fact that he seems convinced that Italy is better at producing spaghetti than boat engineering. It wouldn't be so annoying if the Americans did not learn how to use the surface drives from Fabio Buzzi...
Apart from that, I had the impression that they are pros in their field.
And I also agree that there are some miths on diesel engines.
By the way, I have a 5.7 Mercruiser on my 21' boat on the lake, and it's fun like hell, jumping the waves at 45 kts.
But let me hope that they are pessimistic about the diesels reliability: the two Cats on my sea boat have approximately 700 hrs, most of which spent at 2000 rpm or so, cruising at 9/10 kts.
I'd be pissed off if they will require a major overhaul before 1000 hrs.
Keeping fingers crossed of course !!!
 
Re: Is Cat any better?

I think his main complaint is with with the engines which have been overdeveloped for the basic block design.Engines which now are producing vastly more HP than they were designed for and because of the unquestioned belief than new materials will compensate for the stress made by the extra power produced.It is cheaper to rehash on old engine that to bring out a new one.
Observation of complaints on various forums indicate to me that the old heavy ford/perkins type engines have stood the test of time better than the manufacturer whos engine spare parts cost a fortune?I am sure you can quess which one.

Exercise is bunk.If you are healthy,you do not need it;if you are sick you should not take it.
 
Re: Is Cat any better?

Is that anything to do with a cat having 9 lives?


--
Tides - Never there when you need one.
Wind - Always there when you don't.

KevL
 
Re: Is Cat any better?

I've worked for years on high performance and low revving diesel engines in evrything from motor bikes? to tanks, drilling rigs and boats.
When an engine is designed, they are designed to produce a certain amount of power, with about a 150% overload. When you take an engine designed to produce 150HP, then up rate that engine with oilcooled pistons, turbos, superchargers, intercooler (air & water) scavenge pumps, bigger valves, exotic camshaft profiles, twin injectors, high pressure/volume pumps and all the electronic control goodies, you are overloading the basic structure of that engine, they do not, usually, upgrade the blocks or head castings, apart from selection (blueprinting) The reliability goes down, something will let go!
Water circulation pumps are also not normally uprated.
Take the original chieftain tank engine, rolls royce, designed and produced an engine, 22 liter six sixcyinder, opposed piston, super charged, two stroke diesel/multi fuel, required by the MOD, the tank turned out to be heavier, so they wanted 750hp, rolls said no! The reliabilty would drop. Leyland said no problem and uprated the rolls engine, same block etc. With bigger pistons and new super charger, the engine began to have reliabilty problems, the MOD wanted more power, it wasn't fast enough! they then uprated the engine to 850hp! Half the tanks in the british army of the rhine, could not get to the front gates of the camp! I jest not!! It was finally replaced with a purpose designed V12 rolls diesel, of 100hp the reliabilty problems ended there! Are you getting my point here? Horse power costs money, in fuel, in initial build, in transmissions and in repairs, it's as simple as that! Lower stressed engines last longer, because they are working within their original design criteria. Although, some engines are inherently better than others, due to better design in the first place.
 
Re: Is Cat any better?

Colin
Reference your posting, if we keep revs down, say to 2200 on an engine rated at 2800 thereby reducing the power actually generated by the unit, does this make any difference to the longevity of an engine compromised by manufacturers increasing maximum power in the way you described?
 
Re: Is Cat any better?

By chance, are you all rooting for a major failure of my poor engines?
The real problem is, many of us do not use the boat as much as they would like. At least, I don't.
And I agree that this can shorten the service life of the engines more that the hours themselves.
With regard to the failures due to upgrading blocks designed for lower power, this is a different story.
Sure, that can also be a reason, if the boat constantly needs all or most of the hp the engines can offer.
But I would be scared by a boat which cruising speed is reached at 90% or even more of the maximum rpm.
The usage I was talking about is:
- 2000 rpm out of 2800 maximum (71%)
- 454 nm out of 890 max. torque (51% !)
- 128 hp out of 350 max. power (37% !!)
- 6,7 g/hr out of 19,2 max. consumption (35% !!! tried and tested, believe me)
Should I expect a 6,6 litres diesel engine (wheighing 1500 lbs) to be stressed enough by such usage to go to the dogs at 1000 hrs or so? C'mon, let me hope for something better.
Then, if I let the engines get rusty because I spend most of my time at work rather than in the open seas, that's a different story. Shame on myself.
 
Re: Is Cat any better?

If a modern high performance diesel engine goes to the dogs after 1000 hrs, it was a load of crap to begin with, reference my statement about bad design in the first place. If your engines are stressed as you say, I would expect them to outlive you! Especially at the amount of use they get. Just ensure they are maintained properly, oil changed more frequently, due to lack of use etc. Think about engine heaters, if the boat is laid up ashore or afloat, inhibit the engines when laying up, or start them and warm through everyweek, ahsore or afloat, if you don't want to have gigantic repair bills, look after the beasties! We run diesels on the rig for years, maitaining when and where required, they have literally thousands of hours on them and run at almost flat out all the time, running generators. I don't work on them anymore, dirty smelly things!
 
Re: Is Cat any better?

Yes and no, you may give the engine a longer life, if you work it 100%, and it was an overstressed unit in the first place, it will reward you with a short life, think of a racing car engine, which is designed to blow up on the finish line! Not one yard before! But if the driver is three laps ahead, he reduces power to give the engine more chance of survival, it's re-built after every race, often replaced! the same with any engine. But some engines seem to like having the balls revved off them and come back for more, generally an understressed engine as long as it's working at the correct temperature will last longer than a stressed unit. High revs also means more wear and more stress on the working parts, it's simple physics, well not that simple, but I guess you know what I mean! Give your engines a chance at long life, good maintenance, good oil, an easy(ish) life, they will reward you with years opf sterling service. Unless they were a crap engine to begin with!
 
Re: Is Cat any better?

Thanks Colin for your suggestions.
Engine heaters is something I never heard about.
Actually in the Med the temperatures are usually not that bad, but last january for example I almost cried looking at my poor boat blocked in two inches of ice on the surface of the marina. Not to mention that we slept into at 1~2 degrees, because even the internal heating just refused to work!...
Could you tell me more about these engine heaters?
 
Re: Is Cat any better?

They are available, but don't ask me where, they just screw into the side of the block or somewhere else in the freshwater side, and keep the engine warmish we used them in canada, all the cars have them, lots of boats aswell, we use them on the rigs for emergency generators, instant strt to full power in seconds. So you could try some of the genny manufacturers. I don't know where here, but try asap supplies, or of course you could do a search thingy. Some of them keep the engines at full working temperature, we doon't need that and it would be very expensive in electricity, you can have them thermostatically (big word that!)controlled.
 
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