shaft or outdrive

[wheneverIcan]

I have owned a small outdrive (fairline sprint) and now a shaft drive (Nimbus27) and found the former expensive to maintain and somewhat unreliable with the trim controls. The only problem (so far - touch wood) with the shaft was a very slightly leaking shaft gland which i have come to accept.
In looking for my next boat I am now unsure of the pros/cons of either method of drive and what advantages each has in respect of annual maintenance and more particulary in reliability and performance

Any feedback greatly appreciated
Simon

 

[muchy_]

Regards your leaking stern gland, depending on the type it is recomended that you leave it dripping slightly so that the packing doesn't over heat. Roughly six drips per min I have been told.

 

[paulineb]

I would go for a shaft every time

Pxx

 

[wheneverIcan]

I tend to agree but why???

 

[paulineb]

The shaft is just straight from the gear box to the sea (if that isn't too simplistic) without lots of gears, doughnuts and other bits that go wrong. Keep it simple

I apply the same logic to husbands

Pxx

 

[oldgit]

How big a boat do you want.Have a quick search on forum for numbers of problems with gearboxes on shaft drives and the same for outdrive problems.Compare one with the other, bearing in mind bigger boats are mainly shafts and little uns mostly legs.and remember that you will pay extra for the shaft drives prob around 10-15%.

And the weather for the weekend is...............

 

[wheneverIcan]

I have always been wary of touching the bottom and felf comfortable with the outdrive in the ability to lift it up. i am fortunate with the shaft to have a keel that goes below the prop to protect it - is this normal on boats such as the sealine where you can specify either outdrive or shaft drive options.

 

[wheneverIcan]

I have always been wary of touching the bottom and felf comfortable with the outdrive in the ability to lift it up. i am fortunate with the shaft to have a keel that goes below the prop to protect it - is this normal on boats such as the sealine where you can specify either outdrive or shaft drive options.

 

[c_j]

The facts

Well Princess V40 facts anyway

the V40 came in either shaftdrive or Sterndrive option.

The Shaft drive version is 8 knots slower and £40,000 more expensive when new.

I would much rather have the shafts if all other things were equal but as usual in boating there is a trade off and I doubt your nimbus had the same performance as the Fairline.

Finally Princess withdrew the shaft option on the V40 because to quote "it was better suited as a sterndriven boat"

The Vovo 63's that were in the shaftdrive option would go on for ever. But cost has to be a consideration.


CJ
chris@stone.uk.com

www.stone.uk.com

 

[Guest]

Simple answer, stick to shafts, loads less trouble, especially in salt water.

paul js.

 

[Guest]

Hi Simon,
Like you, I used to own a small Sealine 22sport (in my case!) with a BMW 150D turbo diesel and outdrive. We used to keep it mostly on the Thames and once we had gotten used to handling it, we loved it. Problem was in the second year, strange noises started coming from the outdrive, which cost a year's budget to fix.
The dilemma is: once the outdrive is off the boat and dismantled, every other fault or weakness in that very complicated and inovative drive-chain system, is there to be seen and has to be addressed before putting it back in the water, only a fool would do otherwise.
Coincidently, this year we have just replaced all the major components on both shafts of our current boat (Trader 41+2) including couplings, cutlass bearings, sternglands and engine mountings for hardly more than the cost of that single outdrive approximately 15 years ago. I think the answer lies in the basic simplicity of a shaft system, that every marine engineer understands. None of those expensive special tools required to take on the ingenious job of dismantling or re-assembling an outdrive.
As regards the handling or potential grounding merits, I would be the first to admit that the 'Kick-up' facility of the outdrive was a godsend on the Thames, especially on the higher reaches during periods of 'drought' or when navigating under bridges that had been thoughtfully bestowed with shopping trolleys just under the surface, by the more misunderstood of our community.
Having adjusted to shafts some years ago, I have to say that I much prefer them, both in terms of simplicity and directional stability. I believe that if you respect your boat, you won't take a hard chance on grounding your props or your steering gear. Okay, we all have touched the ground occasionally, but that would usually be a 'touch' with a close eye on the sounder, not a gut wrenching fast take-away!

I would go for shafts every time.

Peter.

 

[ccscott49]

Are you serious, £40,000 pounds? I think thats a little high, but never mind, was that the difference between the engines or just the drives, I cant see all that money, unless of course they have to fit bigger bearers etc etc etc. but 40 grand seems a lot, how much are oudrives?

 

[burgundyben]

I cant under stand why the shaft boat could be that much dearer, seems odd.

I agree with everything that peters said I have driven both types of boat and would only have bought shaft.





I am gonna spend it on wine, women and song, and blow the rest.........

 

[c_j]

That was approximately the difference between the same boat with sterndrives or shafts.

The Engines were much larger of course in the shaft driven version because for all thier critics the sterndrives are far more efficient.

It is so easy to say " I would always have a shaft driven boat" but all I say is consider all aspects.

I would suggest that we all consider that boats with the largest engine option is the best. For instance where two engine options on a forty foot boat the smaller option becomes practically unsaleable secondhand. Therefore the makers often offer two options but in fact never sell one. The comfort of shafts is real but on the V40 with a TOP speed of 30 knots on shafts it has to be considered whether you are prepared to live with that, especially as the sterndriven versions were far cheaper, faster and gurranteed for three years anyway.

Sterndrives give you 36-38 Knots meaning you can cruise comfortably at 30/31

I would never go for a sterndrive flybridge boat (as some are around 40 feet and less) but on a sports cruiser?

Sterndrives.


CJ
chris@stone.uk.com

www.stone.uk.com

 

[ccscott49]

Why are sterndrives more efficient than shafts? Please explain that for me.

 

[Deleted User YDKXO]

2 reasons. First, you dont have shafts, P-brackets (supporting the shafts), rudders and the proximity of the hull itself to spoil the clean flow of water thru the props. Second, the shafts are necessarily down angled to protrude from the hull and some forward thrust is accordingly lost. With sterndrives there are no obstructions to clean flow around the props, the props can be trimmed for max efficiency and duo props can increase efficiency even more
Having said that, I'd have shafts every time

 

[Deleted User YDKXO]

Does'nt the shaft drive version of the V40 drive through V-drive gearboxes at the front of the engines with the shafts coming back under the engines? I think these are v. expensive plus the bigger engines, bigger bearers, sterngland assemblies, bigger starter batteries and far less sales volume = +£40k. Agree that on the V40, shafts not worthwile

 

[ccscott49]

You answered my question on your other post really, nobody mentioned "V" drives etc, now I can see where the money went. Of course when you get to really powerful boats, I suppose shafts take over, as the outdrives, apart from special build=expensive racing versions, can't handle the power, or when we go to surface action props or tunnel props and low angle entry etc. etc. ad infinitum.

 

[nicho]

On the face of it, outdrives have considerable advantages over shaft drive (see the various comments in this thread) - effeciency, ability to lift in shallow water, vectored thrust in close manoeverability situations etc. The biggest fear seems to be for their reliablilty. I have owned six boats all with outdrives from a 23' Searay to the latest, a Sealine S37, with a mixture of Bravo 1, Bravo2 and Volvo duo- props. In all cases , with the exception of one broken gearshift cable (Bravo 2 - fixed under warranty), they have behaved impeccably. One problem area is that you cannot fit rope cutters, so these boats are susceptible to picking up such hazards - the duo props in particular jam solid when caught , often causing severe damage when running at speed. With the single prop version (eg Bravo 1 or 2) then you stand a better chance of unravelling it by nudging in and out of reverse. So, with all these advantages, and in my case excellant reliability, why would I definitely choose shafts if they were available on any boat I wished to purchase?. Is it a case of "give a dog a bad name"...or have I just been lucky not to have the problems so many others seem to have.

 

[Deleted User YDKXO]

I think the max power currently available thru a leisure rated sterndrive is about 300hp so any boat much more than 40' is going to be shaft drive anyway