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Twin engine vs single engine boat

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While my boat sits on land waiting to be looked at, I've been looking at other boats for sale. I came across a couple of boats that are similar. One boat has twin 4.3L engines. The other had a single 8.3L engine.

What are the advantages/disadvantages, fuel consumption..etc etc between the two?

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Advantage - more maneuverable , safety if one engine goes down you have one to get home on,

Disadvantage - double everything winterized, more fuel, higher maint costs,

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to me the biggest issue with twins is the maint. cost and amount of work. I do my own work and I shutter just thinking about maintaining 2 engines/drives!

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for daily engine checks or oil changes that is why i went w/ the Volvo. Impeller is 4 bolts and a hose, and engine oil, fuel filter is right in front and as easy as it gets.

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FWIW ... we did a lot of multiday cruising in the last couple of weeks in mostly windy conditions and after having trouble backing into the various slips and docks, I know my next boat will have twin engines AND bow thruster.

I thought that I did not have enough experience and feel for the boat to back it into the close quarters last year, and the situation has not gotten much better this year.

Frustrated, I've tested how my boat reacts to wind in drift and while idling in reverse. Surprise, the boat's natural drift position is 30-40 degree into the wind (close hauled) and not into the wind (in irons) as one would hope a well designed boat would. Furthermore, the idle in reverse power cannot overcome the force exerted by wind stronger than 5 knots ... it is not possible for my boat to turn into the 5 knot wind while idling in reverse. This effectively makes docking in reverse impossible in windy conditions without pulling the throttle a bit harder which is a risky thing to do in close quarters ... and forget about backing while facing the wind, the boat will rapidly swing from one tack to another once the bow crosses the wind.

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My boat is impossible to handle in reverse. This would be the clear reason to get twins. But as others have mentioned, cost will probably keep me single.

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I had a single engine 26' boat with a 5.7L engine then bought a 05 Signature 310 with 5.7L twins and love it. It's a lot easier to maneuver the boat into the slip just using the engines, except when it's windy, then it's back to the steering wheel again. I noticed that when idling through a no-wake zone that the boat doesn't wander side to side like the single engine boat. On the fuel side of the equation, the 26' averaged about 9.8 gal/hr. where the Chap 310 is averaging 14.6/hr this year.

I changed my oil, oil filters and fuel filters to help reduce the cost of ownership and am on my 3rd year of using the same shrink-wrap and I think it will go another 3 or more years. Where the seams were a little iffy, I re-taped them with shrink-wrap tape. That's a big savings right there. This year I plan to winterize the water system, A/C and generator to save more $$$. The marina will just winterize the engines. Hope that helps

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From what I have heard, two engines don't burn twice the fuel, but about 50% more. The maintenance, of course, will be double.

If you go single engine, I would say a duo prop would be required, since with a single screw you will have control in reverse.

Docking is much easier with the duals, and it's nice to have an extra engine to "limp home" on if required.

Since I plan on living in FL and doing some Bahama runs, I plan on getting a dual engine 31' next.

I agree with above, backing into a slip facing into the wind in a single engine Sig is near impossible, as the bow will get pushed off in either direction with no way to recover in tight quarters. Basically have to keep on the gas in reverse until the last second and then hit forward to stop the motion once in the slip. This technique violates my first rule of docking which is to never approach the dock faster than I want to hit it.

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HAD A SIG 24 FOR 20 YRS AND KNOW EXACTLY HOW YOU FEEL ABOUT BACKING INTO THE WIND OR WITH A CROSS WIND. NOW WITH TWINS ITS MUCH EASIER, BUT THE REAL TRICK IS TO HAVE A BOW THRUSTER. I NOW TAKE THE SPOTS THAT NOBODY ELSE WANTS BECAUSE THEY ARE TOO AFRAID TO TRY. AND TO MAKE IT MORE IMPRESSIVE I BACK IN . WIND, CURRENT, ANYTHING ELSE, THERE ALL A NON ISSUE NOW. I WOULD SAY ITS THE BIGGEST STRESS REMOVER YOU COULD BUY

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My boat is impossible to handle in reverse. This would be the clear reason to get twins. But as others have mentioned, cost will probably keep me single.

Sorry I will say this...you do not need to have two engines to go in reverse.You need to learn manouvering your boat.Every boat ,ship,vessel,has it's own manouverability + reflexibility and her captain will learn these one day.Do not give up.Learn your boat's reflects in the open water by playing with her ,in the calm water,and later in the rough / windy water....:)

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Sorry I will say this...you do not need to have two engines to go in reverse.You need to learn manouvering your boat.Every boat ,ship,vessel,has it's own manouverability + reflexibility and her captain will learn these one day.Do not give up.Learn your boat's reflects in the open water by playing with her ,in the calm water,and later in the rough / windy water.... :)

Yes, we know the boat will go in reverse. Handling in close quarters with heavy winds is another matter, oh ye of infinite skillz and wizdom not bound by the law of physics.

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Are 2 engines easier thatn 1 for manuverablitiy... yes - are they a MUST .... no...

I personally don't have a problem manuvering our boat in reverse now that i've learned how she resopnds to me and how the winds/tides affect her...

I think ours is about as large as I'd wanna go in 1 engine...

If its THAT windy in a marina - I'd prob avoid a stern tie - and go bow in...

but thats just my :Twocents:

good luck with your decision...

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I am new to twin engines. My fishing boat is single engine and I can back that thing into anything without an issue. Learning how to drive this thing with twins has been a challenge but is a learning curve. I think it depends on how big of a boat you get will determine if you want twins or not. I've been reading that a single big block has been performing just as well as twin small blocks. So I think it just depends on you and preference. The twins do require more maintenance cost and gas. But it also allows you the comfort of a backup motor to get back to dock if one engine breaks down. That of course is if you don't have bad gas which will take both motors down .

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I have twins and it's hard enough to "park" it with two much less one. These boats are so tall that the wind can push them left or right pretty quickly. You get use to the bigger bill. It's all just part of the fun!

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cj-orca, absolutelly correct,as you have describe the whole matter.Another matter,probably well known to many captains here in ,but not to all ,is that if a boat has twins and loose the one ,moving with single left able, cannot achieve speed more than 5 knots.Reason is that is not able to be on plane now.Because the one left good is not in the center of the hull.In difference if boat has a displacement hull and not a plane hull,then loossing the one engine usually is able to achieve aprrox. 3/5 of her speed with twins .

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