What's a lot of hours?

benjenbav

benjenbav

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What\'s a lot of hours?

As I have previously mentioned, I am looking to go mobo and have now spent some time kicking the fenders of various 24-28 ft sports cruisers, new, newish and older. Please could the panel give me an indication of how many engine hours might be expected out of, say, KAD32's before they can be expected to become unviable. Thanks in advance.
 
Re: What\'s a lot of hours?

KAD32's will be nicely run in at 1000hrs, and no reason not to keep going until 2000hrs plus. A few blow up at low hours because of poor maintenance. The hours don't really matter, so long as the correct maintenance was carried out along the way, and the engines weren't overpropped (overloaded). It's all about condition and maintenance history, not about the hours !!! The hours tell you when to change the oil etc. That's about it !!!

I sold the old S240 with an AD31XD with well over 900hrs on the clock, and it still started within seconds and pulled over 30knots.

A youngish boat with low hours is a good thing cos it means that the upholstery hasn't been sat on much, but an oldish boat with low hours is not, cos it means that the engines will have sat idle for long periods, hence possible corrosion issues and things getting stuck...

dv.
 
Re: What\'s a lot of hours?

Thanks. That's what I sort of thought, but all brokers seem to go on about how many hours they've done to the exclusion of almost any other consideration.
 
Re: What\'s a lot of hours?

Pleasure boats either have very low hours, or extremely low hours.

I know of a commercially run boat with Volvo TAMD 41's that has 15,000 hours and only rountine servicing. The engineers reckon it'll be past 25,000 hours before it requires anything more than just the usual service.

So pleasure boats with hours measured in hundreds are barely run in. Indeed as far as the diesel engines are concerned, regular use is better than occasional use.

The only area in which "high" (or rather, higher) hours might be relevent is wear and tear on the boat generally. A boat with higher hours may have been used more so things like soft furnishings, carpets etc might have more wear. Not always the case though, a low hours boat might have been used a lot to live on but not been far.

Best to look at overall condition and not fixate on hours at all really.
 
Re: What\'s a lot of hours?

Not sure if it's a fair comparison, but 2000 hours only equates to 60,000-ish miles in a car/ truck. Surely a robust diesel engine should be good for 2-3 times that amount of use.
 
Re: What\'s a lot of hours?

my 3.5l 4 cylinder Yanmar is reckoned good for 10000 - as has already been said it's about the nature of the usage and maintenance cycles.

bit like the difference between a car driven everyday but almost exclusively long trips on motorways and one used occasionally for short hops around town. The latter will be 'wearing' a huge multipul of the former.
 
Re: What\'s a lot of hours?

It should, but head gaskets can fail, coolers get clogged, exhaust pipes go crunchy, water pumps go leaky, the outdrives go clonky: no one item is fatal, but if you have all of the above, it gets more expensive.

Bear in mind that a 2000hr engine used an average 100hrs/year will be 20 years old... If you were to actually put that sort of hourage(?) on an engine in 3 or 4 years, you probably wouldn't see the same pattern of problems.
 
Re: What\'s a lot of hours?

It's all down to what sort of use the engines have had and
how often they were serviced
Case in point Calm Voyager MBM's Mobo done 900 or so
hours, I imagine the majority of those hours were done
at sea, using i would 75% engine power, the best possible
use for marine diesels.
Compare that to a twin diesel engined cruiser pottering
along on rivers and canals doing 5/6 knots or less, engines
revving 600/900rpm, turbos not working, bores getting
polished,smoke everywhere,
I would far rather buy the "High Hours" boat, than a "Low
Hours" boat, given the conditions described above.
Boat engines need to be used, they live in a hostile damp
enviroment, some are laid up for months, to their
detriment. They need love bless 'em. I talk to mine.
Oh! dear i should'nt have told you that!
They are known as Mr Perkins. I will be talking to Cats next!
 
Re: What\'s a lot of hours?

Engine wear is a function of both working hours and time in that a 1000hr/2 yr old boat will exhibit less wear than a 1000hr/10yr old boat. It will also be dependent on the number of cold starts in that, like a car, a boat that has been used for a lot of short trips may exhbit more engine wear than one used for a lesser number of longer trips and, as already mentioned, a boat that has been used for many years at slow speed may start to give engine problems when it is subjected to high speed use. So, its not possible to be definitive about engine wear relative to hours
FWIW and it may not be worth very much, my feeling is that the current generation of highly stressed turbo and supercharged engines will need major rebuilds between the 10yr/1000hr and 15yr/1500hr marks. If I was buying a 15yr old boat with the original engines in them, I'd be looking for large capacity, lightly turbocharged, low revving understressed engines rather than the high revving screamers produced by some manufacturers.
 
Re: What\'s a lot of hours?

[ QUOTE ]

I would far rather buy the "High Hours" boat, than a "Low
Hours" boat, given the conditions described above.

[/ QUOTE ]

Unless the engines have been replaced, then there is no reason why the hours should be low for the age of the boat.

Don't forget the style of engine will also give an indication of how long lasting an engine can be..

I suspect that a high revving, highly tuned turbo charged engine found in many performance boats will not be as rugged as a big block non-turbo engine as those found in some slower vessels and commercial boats like fishing boats.

Steve
 
Re: What\'s a lot of hours?

[ QUOTE ]
I suspect that a high revving, highly tuned turbo charged engine found in many performance boats will not be as rugged as a big block non-turbo engine as those found in some slower vessels and commercial boats like fishing boats.

[/ QUOTE ]

don't think you will get anyone disagreing but I am not sure of the relevance.

The thread is looking at KAD32; leisure engines leisure boats leisure use. Their longevity relative to a low stressed commercial engine run 14 hours a day most days is pretty irrelevant.
 
Re: What\'s a lot of hours?

Only a rough idea how many hours my engine has done as the meter doesn't work. Bought as a recon, hard to know if that should reset the hours or not? Being river based with a turbo I make a point of getting out into the quicker bits when I can. I also suspect that a perfect propping for sea use would have another inch or so of pitch/diameter so at the expense of fuel economy, the engine is working a bit harder.
 
Re: What\'s a lot of hours?

Just background info - nobody had mentioned this so far. When looking at boats a while ago, I looked around a Broom ocean 37 in the broads. The boat was a rusty old tub in terrible condition, yet the perkins engines with 4900 hours on them started from cold within a couple of seconds turnover.

S.
 
Re: What\'s a lot of hours?

Not wishing to hijack…………..but, with all the stuff being said here I am now considering plumbing our new D4 with an Ebo water heater (already fitting it for hot water & rads alongside a Webo 2000s) to pre heat before starting, when time allows, what does the panel think?

David
 
Re: What\'s a lot of hours?

As an alternative, what about something like a Wolverine oil pan heater. Fairly easy to fit (ignoring the ones with elements which go into the pan itself), and keep the oil (and the whole block) warm.

I know a few who recommend them for the Cummins engine I have - but I've not bothered this winter. Maybe next...

Rick
 
Re: What\'s a lot of hours?

Tell me more David, i have to fit aheating and hot water
system in my boat. I have been advised to get a small
domestic diesel fired boiler, small rads in every cabin,
fed by small bore plastic pipes. Run off 240volt in
harbour, or an inverter at sea,bear in mind the actual
electric pump won't draw much juice.
I told the system is great, nice warm cabins, and
"Constant "hot water!! Wodja Fink?? Tony.
 
Re: What\'s a lot of hours?

For what it's worth I would go for the Webasto or Eberspacher or Mikuni or Volvo Ardic water heater, 12v or 24v with no power wasted in the inverter and made for the job. I really don't think domestic equipment that produces deadly fumes has any place on a boat without profesional advice as to it's safety.


David
 
Re: What\'s a lot of hours?

Looks like a good idea Rick, but as I am already fitting the D5W boiler as a water heater I see little point in duplicating. If I didn't already have the Ebo it would certainly be a consideration.

But........ my main question still is do we think that this practice will show any real benefit in reduced engine wear?

David
 
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