Question about Boat engines and there longevity?

[Cole Trickle]

On the way to work this morning I happend to look down at the gauges and noticed that my 2005 Silverado has 350 hours on the hour meter and 13,500 on the odometer.
The new Chevy engines will go 100K miles plus without breaking a sweat and according to my calculations that would be over 2800 hours on the motor.
How long should a Merc motor last providing it wasn't abused and had all reccomended services?
Can you get anywhere near that with a boat motor? Why would a boat motor need to be replaced or rebuilt at 500 hours when that would be less than 30K miles on a cars odometer?
Whats different?(I know boat motors cost alot more than car motors)

[Tom Brown]

Try running your Silverado under heavy load at an average of 3500 RPM for 2800 hours and get back to us.

[Cole Trickle]

Try running your Silverado under heavy load at an average of 3500 RPM for 2800 hours and get back to us.
You clearly have never riden in a vehicle with me. :crossx:
My boat spends more time idling then it does above 3500 rpms.

[Dave C]

IMHO... 1500-2000 for a four stroke, at least.... if its taken care of.
I know some will disagree but you know what opinions are good for ;)

[rivercrazy]

Boat engines never coast. They are always under a heavy load. Similar to towing a very heavy load up a steep grade.
IMO 1000 hours really good life for a marine engine that is very well maintained and not run at 3/4 of rated rpm or higher for extended periods.

[Cole Trickle]

Boat engines never coast. They are always under a heavy load. Similar to towing a very heavy load up a steep grade.
IMO 1000 hours really good life for a marine engine that is very well maintained and not run at 3/4 of rated rpm or higher for extended periods.
So we would be lucky to get the equivelent of 30K miles.....
Maybe the Diesel engines will work out better than I thought in boating applications :idea:
What is different about the Merc 496 then the Chevy 8.1 in the Trucks and Suburbans to justify the huge cost difference?

[Dave C]

nothing.... except the sticker on the top.... LOL ;).....
thats why the wackers guys make fun of us car-motor guys...

[Cole Trickle]

nothing.... except the sticker on the top.... LOL ;).....
Don't forget the extra helping of bend over and take it in the ass :220v: :boxed:

[Speedin' Ian]

I think a boat motor can last a loooong time if it isn't abused and it is well maintained. I used to water ski competively and my parents have an 86 Mastercraft that I trained behind a couple times a week. When it was towing me at 36mph the boat would be taching over 3500 rpms, and when we were cruising at the lake or river it would run at over 3k for prolonged times. Currently the motor has about 1200hrs (very little of it was idle time) and it looks and runs like new. Then it again it is a 351, so that might have something to do with it! :)

[Dave C]

uhhhhh, ya.... that too...... ;) ;)
no shiat.. thats why my next boat its being ordered with NO FRIGGEN MOTOR..... I ain't gonna make that mistake again. :mad: :mad: :mad: everytime I look at it I wanna sell it. :mad: :mad:
some guy joked on here about how to upgrade the 496.. by tieing a chain to it and toss it overboard to be used as an anchor.... too funny :) :crossx:
Don't forget the extra helping of bend over and take it in the ass

[NautiTwins]

I think a boat motor can last a loooong time if it isn't abused and it is well maintained. I used to water ski competively and my parents have an 86 Mastercraft that I trained behind a couple times a week. When it was towing me at 36mph the boat would be taching over 3500 rpms, and when we were cruising at the lake or river it would run at over 3k for prolonged times. Currently the motor has about 1200hrs (very little of it was idle time) and it looks and runs like new. Then it again it is a 351, so that might have something to do with it! :)
We have a Nautique with 750 hours on it and it pulls just as hard as new. We do idle alot though, once she is started for the day I rarely shut it off.

[MagicMtnDan]

Boat engines never coast. They are always under a heavy load. Similar to towing a very heavy load up a steep grade.
IMO 1000 hours really good life for a marine engine that is very well maintained and not run at 3/4 of rated rpm or higher for extended periods.
Assuming that's a good rule of thumb ("1,000 hours is really good life for a marine engine that is very well maintained"):
1. What's it cost to freshen up the motor?
2. How would you approach (how much do you deduct from the asking price) buying a used boat if the boat had say 250 hours on it? How about 500 hours on it?

[RiverDave]

The old Nordic has 550 hours on it, and it runs like a champ.. I did have it completely gone through two years ago, becuase it didn't feel like it was making the HP it used too.. Got it back and it's still the same so that was a waste of a shitload of money.. LOL Overall though it's solid as a rock and I expect it will be till it has over a 1000.. Most of it's life is cruising though.
You heading to the river this weekend?
RD

[OGShocker]

Let's ask Jay Photoglou... :devil: :crossx:

[Tom Brown]

Most of it's life is cruising though.
I'll bet it spent condiserable time idling while you blew your way through a safety inspection.

[Kilrtoy]

Let's ask Jay Photoglou... :devil: :crossx:
OUCH :)

[PHOTOGLOU]

OUCH :)
About the boat motor..... Or the Chevy engine????????