Legs vs shaft

Sailorsam101

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I read a lot of people like legs and the same amount hate them...its just the same for shafts.

As i read it..legs are more efficient but expensive to maintain where as shafts are simple to maintain but suck more power from the engine?

Am i right and what other issues are there as i don't know.
 
Legs give a more manouvreable boat and offer drive trim without inducing drag from trim tabs. With shafts you need water passing the rudders to turn (assuming you're not using engines independently).
 
Legs give a more manouvreable boat and offer drive trim without inducing drag from trim tabs. With shafts you need water passing the rudders to turn (assuming you're not using engines independently).

Your experience is very different to mine as my shaft drive boat is more maneuverable than my previous outdrive boats. There is an efficiency cost to pay as you add in the drag form the rudder(s) and of course the shafts are not horizontal, so there is some vectoring involved. My boat needs very little trim tab.
For me, mooring is much easier with shafts, as the bow is less prone to wind effects.
Outdrive boats benefit from packaging the motors right in the stern, generating more cabin space below decks. Lifting the legs makes the props easier to access for cleaning and maintenance. With shafts, it is a divers job, or lift out.
So there are pro's and con's, and I am steering clear of the maintenance costs, as I assume Oldgit will be along soon :D
 
I read a lot of people like legs and the same amount hate them...its just the same for shafts.

As i read it..legs are more efficient but expensive to maintain where as shafts are simple to maintain but suck more power from the engine?

Am i right and what other issues are there as i don't know.
Well, one point is where the engines sit and what that means for the boat layout-sub 45ft I guess. You probably will not get a choice anyway, once you have decided which boat. I would choose the boat, not the drive system.
The ongoing maintenance is not really the issue with o/drives; the issue is that if it goes wrong, it is not likely to be cheap and then some folk seem to forget that they have had 5-10-15 years without a problem. You just have to amortise the cost and man-up ;)
 
I think a lot of it comes down to the age of the boat. Fred actually sums it up really well, when the boats new and budget isn't an issue they're maintained religiously and reliability isn't much of a problem.
Some Years down the line, maintenance dies off along with reliability as the boat changes hands until you end up with a ticking time bomb with a very short fuse.
It also must depend on the outdrive itself, my elderly 270 gave no end of problems until it finally disintegrated, the recon replacement lasted nearly 2 Years before needing a rebuild. Fantastically economical in that first Year though, I doubt we got through more than a gallon of diesel with the boat being lifted every other weekend...
On the plus side, it's fairly maneuverable, although not even close to the twin screw on shafts (never driven a twin outdrive boat)

The Colvic which has a single engine on shaft and no thruster has absolutely no steering in reverse, and I mean none at all but the simplicity more than makes up for that.

Personally, I'd never, ever consider another boat on an outdrive, but then I'm only ever going to be in the market for boats 20 Years old and (significantly) over although a friend of mine absolutely swears by them and spends just a few hundred a Year on maintenance and minor repairs as needed.

EDIT: Also, to add to that, if you're only in the market for a small boat then you simply won't have a choice. It will be outdrive or outboard only (unless it's an open fishing boat or similar)
 
You can step onto the beach with legs

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We all know there are various posters with various axes to grind on this subject. I have used and owned both extensively and find both equally easy to manoeuvre, stern drives more economical and shaft drives usually cheaper and easier to maintain. The point is though, is that most of us don't get a choice. You want a 40ft flybridge boat, you are probably gonna get shafts. You want a 30 ft sports cruiser, you are probably going to end up with drives. Get the boat you want and live with it. The fuel savings on drives will pay for the extra maintenance.
Whether you choose drives or shafts, the. It's important thing when buying used is to make sure the boat has been well maintained. Most of the horror stories about drives are caused through lack of maintenance.
 
Sterndrives are the manufacturer's pension plan.

Put an engine indside a boat and connect it to a drive, hinged so it can swing and trim/tilt, by shafts and joints running in bellows submerged into the sea. Then add gear shifting mechanisms and a flow of exhaust and cooling water in yet another bellow. On top of it let this device pick up cooling water and run it in a separate circuit, in to the engine through the drive and transom.

Compare that to a shaft. Connected to a gearbox, running inside a tube, with a prop fitted at the end.

If shafts are good enough for Maersk, they will do for me :encouragement:
 
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It's not really much of an argument.

Outdrives work for their application - small to medium sized boats - especially single engined where shafts have no place at all now. As the boat gets bigger then it's easier to relocate the engines elsewhere and use shafts which make more sense. The argument should be shafts vs IPS...

Americans may argue completely as they use outboards on 40'+ boats as they free up all internal space and petrol is cheap as chips.

Personally I'd have a Storebro or Oyster on jets...
 
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