rsn48
Guru
- Joined
- Feb 18, 2019
- Messages
- 2,019
- Location
- Canada
- Vessel Name
- Capricorn
- Vessel Make
- Mariner 30 - Sedan Cruiser 1969
For about the hundreth time (okay I might exaggerate a bit here), I will link the David Pascoe article, almost all discussion questions and suppositions are answered there. For example, the comment below is answered quite well by David:
I'm going to assume the guts of these engines is all the same, so I'd further assume the D3-110 running at full load would be MUCH more durable and long lasting than the D3-220 running at full load. Sound about right?
So says, regardless of modern technology, or maybe because of it, engines don't last as long. He basis is reflected in the old adage - "there is no replacement for displacement." One enemy of engines is heat, so a block engine that supports 100 versus 200 hp is going to last longer in the smaller version. Using turbochargers is a no no according to David, and he is anti-aluminum; all for the same reason - heat.
Someone here was talking about a 454 block engine kind of being maximum for gas engines. Mercury has done away with their smaller stern drive engines and has now only three block sizes, with two hp's available in each block.
I just installed a new Merc 6.2 l which is 378 cubic inches. The new Merc 8.2 l which is 500 cubic inches is the largest other size available.
And so to parrot Pascoe's reasoning, for boats over 34 feet the owner is best owning a diesel engine, under 35 feet a gas engine. This equation based on heat, torque, expense and rebuilds, servicing, life expectancy of the engines and fuel burn.
Here are the inboard Merc engines now available in their own engine build (not an auto engine as they used previously and Volvo still does):
https://www.mercurymarine.com/en/ca/engines/inboard-and-sterndrive/mercruiser/
And for the exaggerated 100th time, David Pascoe's articles:
https://www.yachtsurvey.com/GasDiesel.htm
I'm going to assume the guts of these engines is all the same, so I'd further assume the D3-110 running at full load would be MUCH more durable and long lasting than the D3-220 running at full load. Sound about right?
So says, regardless of modern technology, or maybe because of it, engines don't last as long. He basis is reflected in the old adage - "there is no replacement for displacement." One enemy of engines is heat, so a block engine that supports 100 versus 200 hp is going to last longer in the smaller version. Using turbochargers is a no no according to David, and he is anti-aluminum; all for the same reason - heat.
Someone here was talking about a 454 block engine kind of being maximum for gas engines. Mercury has done away with their smaller stern drive engines and has now only three block sizes, with two hp's available in each block.
I just installed a new Merc 6.2 l which is 378 cubic inches. The new Merc 8.2 l which is 500 cubic inches is the largest other size available.
And so to parrot Pascoe's reasoning, for boats over 34 feet the owner is best owning a diesel engine, under 35 feet a gas engine. This equation based on heat, torque, expense and rebuilds, servicing, life expectancy of the engines and fuel burn.
Here are the inboard Merc engines now available in their own engine build (not an auto engine as they used previously and Volvo still does):
https://www.mercurymarine.com/en/ca/engines/inboard-and-sterndrive/mercruiser/
And for the exaggerated 100th time, David Pascoe's articles:
https://www.yachtsurvey.com/GasDiesel.htm
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