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Old 06-08-2020, 07:19 AM   #21
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To add to Art's comment on power output, every design has a range of power outputs where it'll live a long, happy life. Push it harder than that on a regular basis and the life will get shorter.

In many cases, the later, higher output versions of an engine family are the ones with the most lifespan concern. For example, the 400+ hp 496 and 502 big blocks don't really have anything durability wise than the older, low output big blocks. But they make more power and typically are run just as hard (relatively speaking), so the lifespan is shorter. But if they'd been designed from the ground up for that power output, they'd probably last longer.
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Old 06-08-2020, 08:39 AM   #22
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Newer engines do last longer than the old mess produced iron.

The main reason is the assembly , parts selection , is now computer organized.

With the shape of a few hundred pistons to chose from a far better fit for todays oval pistons is easy.

Same for connecting rod weight and length , and most other engine parts.

Back 50+ years ago race cars used seasoned blocks as the heat and stress of running reshaped the block, machining would true it , so it could last longer at high RPM.

Today computer design and experience allows better, more accurate machining.

THe new engines are as easy to kill from neglect , the right oil and antifreeze are required.

I believe most boat engines are killed by not following Da Book, (the maint handbook) about proper out of season storage.
Fred - You hit the Bulls Eye! New, improved materials and build techniques enable most portions of drive lines to last much longer than old school methods.

I've owned a lot of vehicles... cars, trucks, boats... etc. Oldest was a 1949 Dodge "Job Rated" stepside pick up. Newest [own it now] is 2014 Lincoln MKT SUV - great vehicle; 82K miles. Seems nearly unbelievable... But, their drive lines are lasting up to 500K miles [livery companies have them for sale all over with 400K plus miles]. Many Cads, Buicks. Chevy's and assorted muscle cars during the years. Even owned a 1969 "automatic stick shift" VW Bug in the early 70's... I hated that car! Traded a 1964 Chevy Impala SS w/ 409 engine for that pos. My ex wanted a small car.

Currently own a really nice 1967 Buick Wildcat. Even after all possible care for its 430 cid / 360 hp engine... due to suddenly increasing blow-by, that muscle-car engine needed complete rebuild at 125K miles. I've only put about 12K on the rebuild... Runs really strong, sweet!

I currently have vehicles [two boats, one truck] with total of 4 pre 1990 GM 350 cid V8's. Luckily those engines run well, one fully rebuilt 13 yrs ago, another full-on top end rebuild at same time [those are in our 1977 Tolly] Not needing to put too much time/miles on any of the 350's. I also have a 1998 4 WD Explorer with 203K miles. Runs like a champ - newer materials and buildout methods compared to the old school days.

Long and short of it: Regarding engines/drive-lines... "They just don't build em like they used to!" Thank God!!

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Old 06-08-2020, 10:59 AM   #23
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Yes Art,
When I think of how nice it would be to DRIVE an old car I surely don’t want to own one. Breaker points, 6v batts, bias tires, and much else I do like my modern car .. 06 Avalon Limited.
One of my reasons to not have an old car anymore is that they really don’t fit in todays parking spaces.
But I’d like a 61 Nash Rambler wagon. It was MT’s car of the year.
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Old 06-08-2020, 11:30 AM   #24
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Yes Art,
When I think of how nice it would be to DRIVE an old car I surely don’t want to own one. Breaker points, 6v batts, bias tires, and much else I do like my modern car .. 06 Avalon Limited.
One of my reasons to not have an old car anymore is that they really don’t fit in todays parking spaces.
But I’d like a 61 Nash Rambler wagon. It was MT’s car of the year.
Eric

Regarding fitting in parking spaces. Our 2014 Lincoln MKT is about as big as our 67 Wildcat. 61 Nash was cute. Wildcat gets less than 3K mi per year on her. This year... who knows... maybe less than 1K or 2K. Whole new world for 2020. Today I plan to get our RV ready for trip to Oregon, family visit. General check up, clean up, tomorrow smog check... and that type o' stuff.

BTW - You or anyone else noticed that "spell check" on TF has gone wonkey for the last several weeks??

Sometimes it undelines a spelling error and will correct... sometines it won't underline and sometimes even if undelined it will not do a correction. Maybe it's just my computer... however, in no other instttance have I noticed any problem with spell check.

I leat several words missspelled in this sentence and the paragraph aboive!!
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Old 06-08-2020, 12:29 PM   #25
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FF wrote;
“Newer engines do last longer than the old mess produced iron.

The main reason is the assembly , parts selection , is now computer organized.

With the shape of a few hundred pistons to chose from a far better fit for todays oval pistons is easy.

Same for connecting rod weight and length , and most other engine parts.

Back 50+ years ago race cars used seasoned blocks as the heat and stress of running reshaped the block, machining would true it , so it could last longer at high RPM.

Today computer design and experience allows better, more accurate machining.“


And I’m sure this is just a scratched surface.
This is one of the biggest reasons I usually vote for a re-power when one of us is debating whether or not to scrap the old FL.
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Old 06-09-2020, 01:29 AM   #26
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Hours are for scheduling maintenance, not determining lifespan.
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Old 06-10-2020, 01:44 PM   #27
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"Hours are for scheduling maintenance, not determining lifespan."


Yes, Total fuel burned or perhaps HP per cubic inch of displacement is a better concept
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Old 06-10-2020, 02:04 PM   #28
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Newer engines do last longer than the old mess produced iron.

The main reason is the assembly , parts selection , is now computer organized.

With the shape of a few hundred pistons to chose from a far better fit for todays oval pistons is easy.

Same for connecting rod weight and length , and most other engine parts.


I just re-powered with the new Mercruiser Stern drive 6.2 350 hp. Mercury decided that using auto car engines in a boat was making less and less sense so they designed the new motor taking only boating needs in mind. More attention to heat and corrosion problems, more torque over the spectrum, etc. Of course we won't know how well these engines will hold up over time, but at least moving away from auto engines seems to be a good call.
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Old 06-10-2020, 02:14 PM   #29
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Newer engines do last longer than the old mess produced iron.

The main reason is the assembly , parts selection , is now computer organized.

With the shape of a few hundred pistons to chose from a far better fit for todays oval pistons is easy.

Same for connecting rod weight and length , and most other engine parts.


I just re-powered with the new Mercruiser Stern drive 6.2 350 hp. Mercury decided that using auto car engines in a boat was making less and less sense so they designed the new motor taking only boating needs in mind. More attention to heat and corrosion problems, more torque over the spectrum, etc. Of course we won't know how well these engines will hold up over time, but at least moving away from auto engines seems to be a good call.
I thought those new Mercs were still based on a GM LS block, just with some minor tweaks and better attention to the marinization process?
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Old 06-10-2020, 02:36 PM   #30
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Gassers are getting tired at 1,500 hours, very tired and showing symptoms at 2,000 hours and generally dead or nearly dead at 2,500 hours.

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Old 06-10-2020, 05:48 PM   #31
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Gassers are getting tired at 1,500 hours, very tired and showing symptoms at 2,000 hours and generally dead or nearly dead at 2,500 hours.

pete
Not necessarily true.

There are variables but I have personal experience with some mid and some large blocks that are tormented in commercial use and blow by 2000 hrs and never look back.

I have heard of many gassers going past 2500 hrs but often get replaced because of feel good reasons...not actual mechanical tests.
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Old 06-10-2020, 05:56 PM   #32
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Not necessarily true.

There are variables but I have personal experience with some mid and some large blocks that are tormented in commercial use and blow by 2000 hrs and never look back.

I have heard of many gassers going past 2500 hrs but often get replaced because of feel good reasons...not actual mechanical tests.
200 hours a year is not out of line for annual use, so you’re rebuilding an engine very 10 years? I don’t buy it. Maybe for raw water cooled but for a closed loop system with heat exchangers?
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Old 06-10-2020, 06:56 PM   #33
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I thought those new Mercs were still based on a GM LS block, just with some minor tweaks and better attention to the marinization process?



Mercury MerCruiser’s new 6.2-liter V-8 300hp and 350hp sterndrive engines, which are purpose-built specifically for marine use, deliver increased power and torque while providing a remarkably quiet and smooth ride.

“With the introduction of our new 6.2-liter V-8 sterndrive engines, Mercury continues to build on its success of designing and manufacturing propulsion systems that deliver the most intuitive, powerful, worry-free, smooth and quiet boating experience,” said John Pfeifer, president of Mercury Marine. “Like the purpose-built 4.5-liter V-6 sterndrives we introduced a year ago, we’re extremely proud of the remarkable reliability and ease of maintenance delivered by the 6.2. This is a terrific engine platform that will improve boating everywhere.”

Engineered with new innovative features and state-of-the-art technology, the MerCruiser 6.2L sterndrive platform was designed and is manufactured at Mercury Marine’s world headquarters in Fond du Lac, Wisconsin. Just like the recently introduced MerCruiser 4.5L V-6 platform for 200hp and 250hp engines, Mercury designed and builds the 6.2L engine specifically for marine use rather than adapting and marinizing an automotive engine. The 6.2L is not burdened with automotive restrictions and unnecessary technologies that result in additional cost and complexity without adding value. The result
is a perfect balance of power, easy maintenance, superior corrosion-resistance and a quiet, pleasurable ride.


And here is a short video, you only need to listen to the first minute:

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Old 06-10-2020, 07:10 PM   #34
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Pete,
I’ve got an old 87 Nissan Stanza w 300+kmi on it.
The engine’s fine. But the steering rack, transmission, struts, and spots of rust like at the bottoms of doors aren’t so good. The engine clearly lacks some compression. One needs to slow shift to not work the synchromesh too much.

But the engine’s done 300k gracefully I’d say.

40mph for 2000hrs = 80,000miles. Even a 36 Chevrolet could do that w reasonable care and moderate driving. I have a more positive view of gas engines.
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Old 06-10-2020, 07:52 PM   #35
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I've a friend who had a 32ft lobster boat with a Ford 351 Cleveland in it, he'd change engines every 3000 hrs. It didn't matter if the engine was still running good out it came. His wasn't any fancy marinized version so they were cheap. As diesels have gotten stupid expensive and less reliable, for the right boat I think a gas engine makes sense. The other thing that amazes me every time I'm on a boat with a gas engine is how smooth and quiet they are compared to a diesel.
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Old 06-10-2020, 09:59 PM   #36
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I've a friend who had a 32ft lobster boat with a Ford 351 Cleveland in it, he'd change engines every 3000 hrs. It didn't matter if the engine was still running good out it came. His wasn't any fancy marinized version so they were cheap. As diesels have gotten stupid expensive and less reliable, for the right boat I think a gas engine makes sense. The other thing that amazes me every time I'm on a boat with a gas engine is how smooth and quiet they are compared to a diesel.
Having pleasure boated 60 + yrs...

For general pleasure boating and considerable amount of small work boats:

- Below 40' to 45' [depending on boat weight and use] gasoline.

- Over 40' to 45" [any boat weight and use] diesel.

It's really pretty simple... Do the math!!!

Then, enjoy the enormously reduced costs, substantially mellowed sound and greatly reduced odor from gas engines.

Each to their own!
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Old 06-10-2020, 11:44 PM   #37
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Pete,
I’ve got an old 87 Nissan Stanza w 300+kmi on it....
Remember the Nissan 200B? Much like the 180B but with 20 new faults.
Good thing about current gas engines is fuel injection eliminating some leak opportunities. And the rebuild cost and reman block and parts availability.
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