Engine choice

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I recently read a post about single engine versus dual engine on a downeast style boat stating the single was preferred on this type of boat .Just curious why
 

Old Mud

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leaky

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One of the great things about downeast boats is the keel protects the prop from entanglements and/or floating objects. It's an eloquent single engine design - the driveshaft runs through the keel, which also holds the bottom of the rudder in place. I know a lot of people stress protection of striking bottom, but pretty much I've got no concern about that and a whole lot of bad experience entangling gear - which is rare and very hard to do at speed with a downeast (we tend to find gear in the open ocean at night, at cruising speeds). If you go to twins on a downeast you just stuck your props out completely unprotected, which is a big downside I've found to basically be as dangerous as striking bottom, since it can not only disable the boat but also can rip things apart.

Talking inboards, if I wanted twins, I'd go to a different style of hull. A downeast with a cut down keel and/or a pair of props & rudders hanging off the bottom is not quite a downeast. It doesn't mean they are bad boats just if I have 2 engines and my props are going to be hanging in the danger zone I'd rather gain the benefit of a more efficient fast cruise speed (downeasts are more efficient and can go fast, but if you want to cruise at 25+ knots the deep V hulls are more efficient and capable of it).

Talking outboards - I think pretty much anything with outboards, say with > 200 HP or so, is better with twins - don't care what it is. Generally twin outboard boats perform better while also burning the same or commonly less fuel than single engine equivalents. It's twice the maintenance and a little extra up front cost, but a much better boat if you ask me.

Twins are very nice for the sake of redundancy and generally speaking you should never need a tow.. but it's also much easier on the wallet to stay on top of a single engine, even for instance when it comes time to consider a major overhaul or repower, people tend to run twin engines longer (and in worse shape) partly because the cost is more prohibitive.
 

Brooksie

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All that said above plus: One engine can be lower in the hull allowing for no motorbox in hulls as small as 34'-35'., single is less expensive to buy and maintain, & run, resale poor on a downeast with twins.
Had a friend many years ago who would always deride me saying one day he would be towing me in b/c I had no second engine like he had. Turns out, when the day came, it as I towing him. Although he had that second engine, he could only go in circles using one engine...
 

leaky

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All that said above plus: One engine can be lower in the hull allowing for no motorbox in hulls as small as 34'-35'., single is less expensive to buy and maintain, & run, resale poor on a downeast with twins.
Had a friend many years ago who would always deride me saying one day he would be towing me in b/c I had no second engine like he had. Turns out, when the day came, it as I towing him. Although he had that second engine, he could only go in circles using one engine...
What kind of boat? This is pretty unusual, most twin engine boats can do an easy 8 knots on a single, straight no less, without beating on the running engine - sometimes 10 or 12 knots on a single wide open but it's not good to do.

The other consideration is generally you stabilize a boat better with the engines toward the rail (which of course a deep V hull needs badly!)..

I like the single engine downeast, don't get me wrong, but you are less self sufficient, no way around that.
 

Diesel Jerry

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I have driven many boats in tight marina’s. I found having two engines provided much more maneuverability. Even over single engine with bow and stern thrusters.
if I were building a 45 or bigger and the budget permitted it I would go twin engines no doubt. I have driven twin engine with one motor down and it was a bear, but I wasn’t stuck in circles. Casco Bay is pretty dense with gear and my twin stick customers have few issues, but they are also running Spurs.
 

Old Mud

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Diesel Jerry

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Some good points Jerry BUT i think about things like Twice as many engines and systems, Twice the fuel and plumbing, Twice the shafts, Struts, Props, rudders and systems. All those things need twice the maintenance.Twice the money and on and on. I guess i still say Yes you can have one engine you just have to take very good care of it. Hell there are thousand of ships running on one engine.
Oh trust me I know. Depending on your financial situation it may not be the best route.
 

goin4broke

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All I have ever had were single engine boats. Of all the hundreds if not thousands of hours spent on the water I can only count a few times when I was completely disabled and probably three times where the damage was self inflicted. Of all the boaters with twin engines I have known in my boating lifetime they have always had an "issue" with one of the two. Port side runs a little hot, starboard runs a little rough, port goes through more oil, starboard sounds funny when backing up etc. etc. etc...... The one engine I have always owned gets all of my attention.

Jerry does bring up a good point about maneuverability which is the biggest advantage. you can fight alot of wind with twin screws.
 

TCL

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FYI, you can have twin engines both with protected props...here is the proof.
I don’t think this design is widely used however.

Good-grief...the picture is right side up on my iPhone.

298E3DB6-9166-4797-AB9F-823EB684DF09.jpeg
 

steveinak

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Some good points Jerry BUT i think about things like Twice as many engines and systems, Twice the fuel and plumbing, Twice the shafts, Struts, Props, rudders and systems. All those things need twice the maintenance.Twice the money and on and on. I guess i still say Yes you can have one engine you just have to take very good care of it. Hell there are thousand of ships running on one engine.
Double Trouble
 

Tuna Pursuit

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I call a twin engine a tender bottom. I've owned a Hatteras and a tiara both twin deisels and they were both magnets for anything floating in the ocean, especially running at night which I've done alot of. If your going to buy a full keel semi displacement downeast putting twins kind of defeats the reason for having that type of boat. Just buy a twin planning boat for half the money if you like the look get a sabre(sabre is not half the money though)
 
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