High engine hours

[dweller]

20 years ago, I worked at a sailboat yard. An anxious owner had 6000 hours on his yanmar and wanted it overhauled. The diesel mechanic (excellent) tried to discourage him, saying there was no reason, but the nervous owner insisted. So he tore it down. He showed it to me and everyone else in the yard. He said it looked like new, and it did. He put the engine back together and told the owner to never come back.

 

[Duetto]

we have the exact same boat (2003) with the exact same engines (3600 hrs). we've had it for 17 years. 5 round trips ct-bahamas, 12 trips fl-bahamas. have never had a problem with engines. pdq over pitched props from the factory. i had to have 1" pitch removed to be able to make 3800 rpms.

on another subject, see if the po had the extra cutlass bearing put in the front of the stern tube...that's a biggie.

you may want to drop in to pdq owner's forum PDQ OWNERS FORUM - Index page

 

[Capt Ray]

Engine hours are very deceptive. If you make a 5nm trip at 5 knots it will log 1 hour on the meter. If you make the same trip at 10 knots you will only add 30 minutes to the meter. If a boat is run hard all the time it will show lower hours than a boat that was run at moderate speeds. Which boat would you prefer? The real measure is gallons of fuel burned. Just sayin'

Yes! I have found it interesting in talking with some folks-in-the-know about my CAT with 2000 hours on it, which just had the 2000-hour service done.

Everything relating to periodic maintenance and repowers is now specified in gallons-of-fuel instead of engine hours!!! Very interesting change... and for the reason you point out!

 

[TomCat]

I've seen Irish Lady listed on the Curtis Stokes site recently but the brokers are not returning calls. Is she still on the market or are you the new owner?

 

[mbdana]

Diesel Engine Hours

Our 34 year old CAT 3208NA purrs like a kitten at 7300 hours. Although the manual says an overhaul maybe in order after 25000 gallons of fuel used (@2gal/hr) we are still along ways away, our CAT expert, John Pride says, that for this engine with the proper maintenance, the longevity would more likely be 20000 hours....which, at my calculations won't happen in my life time or the boats life time.

3200 hours for a diesel engine is just broken in.

Best regards,
Mike Dana
Third Reef
36' Grand Banks Classic #819
Potts Harbor Maine

 

[Hippocampus]

Never fully accepted that fuel burned is a total measure. Agree it better than hours but think it’s not the total picture. Believe much wear occurs at startup before lubricants are warm and flowing under good pressure. Same when shutdown if done incorrectly not allowing turbo and other things to spin down and cool a bit. So think a engine that goes on and stays on for a long time is a very different beast than an engine that is only subjected to brief runs even if both have the same fuel burned.

 

[rslifkin]

Never fully accepted that fuel burned is a total measure. Agree it better than hours but think it’s not the total picture. Believe much wear occurs at startup before lubricants are warm and flowing under good pressure. Same when shutdown if done incorrectly not allowing turbo and other things to spin down and cool a bit. So think a engine that goes on and stays on for a long time is a very different beast than an engine that is only subjected to brief runs every if both have the same fuel burned.

Agreed. Number of operating cycles is a factor, as is cycle length. Short cycles that don't get everything up to full temp plus 15 minutes or so beyond that lead to more fuel dilution in oil, more moisture in the oil, etc. that all lead to a little extra wear. Stuff like rings, etc. wear a little more during warmup when things aren't quite at their optimal size and shape as well.



Storage environment while not operating matters too. An engine kept in a fairly constant temperature environment without excessive humidity and with an exhaust system that doesn't keep much moisture close to the exhaust valves, turbo, etc. will live longer than one that sees lots of temperature change and high humidity (and regularly gets condensation in / on all sorts of parts).