Engine hours

Danny_Labrador

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What's a reasonable life expectancy for typical yacht diesel engine (hours).

Say a Volvo MD22L or a equivalent Yanmar

What's hours for:-

just run in ?

major overhaul required ?

knackered ?
 
I dont think you can predict that. It all depends how the engine has been used/abused and serviced during its life.

Clearly a regularly serviced engine will last many 1000 hours, whilst one that is left ticking over or run without load, charging batteries or not had regular oil changes will die earlier.
 
Big thread on this a coulpe of weeks ago ....... but I cant find it now.
I have a Yanmer 3GM 30 with about 4000 hours onit still going strong. I think general wisdom says a normal life expectancy is about 10,000 hours before major overhaul. Depends on the treatment it had tho!
 
Wow 10K!? So my 13 year old boat with 1100 hours on the engine should keep going for about another 105 years! Great I dont need to budget for engine overhaul!
 
Have a look at some flotilla lead boats, although not many of them seem to have hour meters. Used every day for years, many accumulate tens of thousands of hours without overhaul. When my son was in this business he reckoned that the engine in his boat had done at least 25,000 hours.

On the other hand, an infrequently used engine, or worse still one that is run weekly during the winter for ten minutes 'to see if it's OK', may struggle to reach 5000.

My Yanmar 3GM30 has now done 1600 hours. It is serviced regularly and is used in a way that I think is best for it. It has the original belts, which still display the silver paint that the engine was sprayed in. Other than oil, filter and impeller changes it has never had a finger laid upon it. It is utterly dependable and runs as sweetly now as it did when first installed.
 
10,000 hours is the normal expected life of a diesel engine in ideal conditions, this can be halved in 'arduous' conditions i.e. continuous stop start variable load short runtimes. Such as a short run motoring from your berth to open water, stopping the engine, sail all day, run engine for a few minutes back to berth. Add in light load running- charging batteries- motor sailing where the sails are doing most of the work. All this conspires to shorten the life of a diesel engine. Add in the marine environment, lack of maintenance accessability, out of sight out of mind. The poor old sailing yacht diesel doesn't stand much of a chance at longevity if not maintained regularly and 'exercised' properly.
 
Dunno, but my MD22 has done 902 hours without major overhaul, so maybe that is a starting point?

/forums/images/graemlins/laugh.gif

And I agree that the worst thing to do is letting it run for 10 minutes just to check that it is OK!
 
10,000 hours I was told. That is an awful lot of hours too... I have just purchased an 11 year old yacht with 1670 hours... 20000 nm on the clock, so I reckon the numbers work out. Sounds as sweet as a nut!!! No probs.
 
Perkins reckon 12,000 hours before a major overhaul. Mine has done 3,500 now and feels nicely run-in. I know of another that has done 40,000 and is still good. Some of the manufacturers who sell high-revving engines recommend an overhaul after just 3,500 hours.
 
Depends on how you use it, what quality of fuel etc etc.

I expect mine to still be running when I have to give up sailing, or when I can't get spares ie over 50,000 hours now on 5,000hrs. Planning a top end O/H at 6,000hours

I see chaps are still saying you have to change the oil every autumn, indeed PBO says serious damage will occur if you do not. Well unless you have used high sulphur fuel and done thousands of hours in 1 year this is crap.

I only change the oil in any engine, compressor etc when the analysis shows it needs it. in the yacht this is usually required after 3/3 years due to condensation water dilution. Same applies to my car, now over 200,000 miles and work engines ( aggregate power over 20MW). If a little centrifuge spinner was fitted to seperate suspended solids and water I suspect the oil could well last the lifetime of the of an engine on low sulphur fuel, combustion checked maintence program these days. Even in the 70s fitting these to geny engines tripled the life of the oil.

It seems most authors have not progressed in their knowledge since the Ford 105e side valve engine routines when a decoke was needed pretty nearly every year. Most of them continue to trot out the SOS.
 
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