how old is old on diesel engine

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I know from my mechanic day a N/A engine would out last a turbo engine...
My Dad used to say that and maybe years ago that was true but things have gotten better. You can't find a heavy truck with a N/A engine, there're all turbo'd and class 8 trucks work pretty hard and any repair work is complained about. It's when marine diesels get pushed way beyond reason that they start failing early. The 6-71T would last a long time at 350 Hp but when pushed to 485 they're so far beyond what's a reasonable life expectancy.
 

05bill

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Must mean something ,haven't figured it out yet.

Thanks
 

Lion's Paw

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The damage control levers are right there within the captains reach.
if properly installed and serviced then run within their rating most diesels will put in a amazing service life.
I got 13k on my volvo and ran strong when sold. 6+ on my 3126 and ran fine when sold next owner ran them another ten years. My 3208s just chugging along fine after ten years and over 5k. Diesel in my truck closing in on 500k miles. Dont cheat your maintenance, especially the cooling systems.
 

Tunacious

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It is all about the maintenance schedule and running them at proper load. The San Diego fleet runs over night, 3 day, 7 day and up to 17 day trips from April to November. The engines are rarely shut down, except at the fuel dock and when reloading a new group of passengers. More damage occurs when an engine is neglected by poor habits of the owner.
 

steveinak

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don't push the red knob all the way to the windshield that makes them last a lot longer, i love hearing the mechanics that say "they are made to run wide open run'em hard" yeah right to the rebuild shop.
 

Diesel Jerry

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snowstorm

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don't push the red knob all the way to the windshield that makes them last a lot longer, i love hearing the mechanics that say "they are made to run wide open run'em hard" yeah right to the rebuild shop.
wrong
 

fishcrazy

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don't push the red knob all the way to the windshield that makes them last a lot longer, i love hearing the mechanics that say "they are made to run wide open run'em hard" yeah right to the rebuild shop.
I’ve heard this many times!! But my dad always ran our 454s easy. We had twins in a 31 Bertram and they ran almost twenty years with no major issues. Not diesels but same principle applies. Routine maintenance was the key and not running them to the pins. We would maybe open them up on the way in just to “clean them out”. I miss those days on that boat. I didn’t realize how good they really were until they were gone. Some of the best days on the water were out on that boat with my dad and those 454s!
 

traditions

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My Dad used to say that and maybe years ago that was true but things have gotten better. You can't find a heavy truck with a N/A engine, there're all turbo'd and class 8 trucks work pretty hard and any repair work is complained about. It's when marine diesels get pushed way beyond reason that they start failing early. The 6-71T would last a long time at 350 Hp but when pushed to 485 they're so far beyond what's a reasonable life expectancy.
671 was 210 hp with n 60 injectors I think.They would las5 forever
 

steveinak

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We don’t do that here. This isn’t The Hull Truth. If you believe someone is wrong offer your perspective and any facts you have. Just saying “wrong” only make you look an idiot that doesn’t know how to have a conversation. I am sure that is not the case.
Right
 

Ditchdigger

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don't push the red knob all the way to the windshield that makes them last a lot longer, i love hearing the mechanics that say "they are made to run wide open run'em hard" yeah right to the rebuild shop.
Steve, I will say that that old motor [39 years] in your boat still starts, and goes. As much that is said about Volvos, some of them were built to run for a long time if they were treated well. That motor only ran in it's sweet spot, or slightly above. Old iron is not efficient as the new stuff. It can take a beating if it has to, and is easy to fix . That is all the efficient that I need. Simple is good. It is also efficient once you have to call in a mechanic at $150.00 an hour.
Hold on to the old iron as long as it is feasible. Picking up a few gallons per hour on fuel burn cannot come close to calling for a mechanic to fix something . The average knucklehead like myself can usually figure out where the problem exists in an older motor. Newer motors with all the computer stuff makes you a fish out of water. Call NASA ! Heard many horror stories of the "Limp Home Mode" from 75 miles out.
I can change fuel filters, and bleed injectors, and prime them if needed. Don't know Shit about no computer stuff controlling my motor. Fuel and air is all that is needed usually to run old iron diesel engines. Don't shut them off, and they won't stop running until you have run them dry of fuel, or lock them up with no oil, or no water to cool them. Simple is SO Much Better !!! Just my thoughts !
 
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671 was 210 hp with n 60 injectors I think.They would las5 forever
I said 6-71T. Original 6-71 was 165 hp. natural aspiration. 6-71T was turbocharged. All of them up to around 350 hp hung in there pretty well. My point was that just turbo'ing them didn't really cut their lifespan until the horse power was really raised.
 

traditions

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I beleive the two piece pistons was the death of the high power 671. The6 tried to clean them up a bit, and lost the reliability. All the GM ‘S were amazing, considering how many parts were interchangabe.Fished o; a eastern rig that had a 1671, basically two 871‘ together. Parts would fit 471 also.
 
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Two piece pistons were only a problem with long idle time. Skirt would cool and slap around in the liner causing excessive wear. Difference was shown in engines that sat at idle just to idle and ones that were run up just a little to run PTO's. Death of the high power 671's were pushing power past 1 hp per cubic inch and marginal and poorly maintained cooling systems, both water and air sides.
 
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Also emissions put the 2 strokes away. It's not all bad. Rodger took it over from a failing branch of GM and got the Series 60 going. You don't see them in recreational marine but they're out there in workboats, making owners money and not taking much in return. Got Detroit Diesel from failing to the engine of choice in a lot of commercial markets.
 

joe4852

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Have a friend with 471 that is 43 years and still running! in a Stanley, one major. Runs as a lobster and stick boat, although the pulpit hasn't be on in a few years. still a screaming Jimmy. 2 stroke 105 HP NA @ 1800 RPMs. On a calm day you can hear it for miles. Not relevant to new motors but part of marine history for sure. When I asked him how often he changes the oil in the TD gear he said "whenever the line blows" . true story.
 
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