how old is old on diesel engine

05bill

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for discussion, how old is old for a diesel engine , hours, years, manufacturers, i.e. Volvo, Yanmar , Cummins ?
 

Diesel Jerry

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DotRat

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27k hours on my cat C15 not a marine engine but it hauls some weight! 2001 Mack CH613
 

Keelboater

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Marine age and lack of parts are the only things that really make them old. You can control marine age with good routine maintenance. If you have a very popular motor, parts should not become an issue. Granted technology keeps changing. Maybe some year we all burn hydrogen. Who knows.
 

DotRat

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Marine age and lack of parts are the only things that really make them old. You can control marine age with good routine maintenance. If you have a very popular motor, parts should not become an issue. Granted technology keeps changing. Maybe some year we all burn hydrogen. Who knows.
I wish!
 

captjohn

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Depends a lot on how the boat is propped, and how hard it's run. If their over propped, and run hard, they can get "old" pretty fast. Under propped, not run hard, and maintained, they can last a VERY long time.
 

05bill

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Thank you guys.

Now how do you tell if engine has been run " hard" ?

Leak down test ,compression test ,prayer ?

Thanks
 
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Thank you guys.

Now how do you tell if engine has been run " hard" ?

Leak down test ,compression test ,prayer ?

Thanks
The turbo outlet pipe to the charge air cooler will be discolored on high hp engines that run hard as the charge air temp can get to 400 degrees under load. That's the intake air not the exhaust. For surveys, compression tests on diesels are too expensive and time consuming so we used crankcase pressure readings at full load. A specific sized orifice was put in the blowby tube and measured with a manometer at full load. I wouldn't even take the time to hook this up if when I put a shop rag over the oil fill opening it blew off when I started the engine.
As for life expectancy, if all maintenance was equal, especially to all parts of the cooling system (water and air sides) the less power from a particular size engine you try to get the longer it will last. A 180 hp or 270 B Cummins will outlast a 480 QSB when run at the same speeds.
Captjohn is right. Duty cycle affects engine life. How is the former owner running it and what's its load? Over propped, a lot of high RPM, or extended idle time?
On bigger engines we're moving away from maintenance overhauls based on hours and moving to overhauls based on gallons of fuel burned. A ship docking tug that spends hours on station waiting and then runs hard for a short time assisting a ship doesn't put the same wear on it's engines that a tug running all out pulling barges back and forth to Hawaii does even though the engine hours could be the same.
Over propping and poor cooling system maintenance are the two things I most often see that wear out marine engines.
 
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Ditto. I have a Ford Lehman in one of my boats (custom boat) that is over 30 years old and I don’t remember the hours on it. My dad has 17K and will be hitting 18K hours on his 6BT this year. He has friends with over 20K on the same engine. Maintenance, how the engine is run, rating from manufacturer all play into it. I have witnessed what poor maintenance can do, and seen how long an engine will last if well taken care of.
I see a lot of boats go for sale that have 5K on a Diesel engine and buyers run away without giving the boat a good look.
I agree Jerry, my custome 32 DE was built in the Frank Sample yard in BoothBay in 1979 . She has her original 42yr old Lehman Diesel [ a tractor engine, really] She's a pleasure cruiser boat with less than 3k hrs. A mechanic joked that engine is barely broken in. If I maintain her maybe that engine will still be running when I'm in the ground.
 

Genius

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horsepower(fuel) divided by liter of displacement x time is your formula......kompressor or turbo, it's all the same.
 

05bill

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Confused again what does that give me ?

13 gph ÷ 3.6 = 3.61×2200hours = 7944 ?

What's it mean ?

Thanks
 
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