bobrose
New Member
I think you have may my mind up , thanks
Outdrives V Shafts
- Thread starter ian38_39
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henryf
Well-Known Member
I just like the simplicity of shafts. On the phantom 42 we changed the cutlass bearings just before we sold it and that was the sum total of our expenditure. On the targa 35 annual leg servicing bills were significant.
On the Princess costs have been zero. Actually that's not strictly true. Currently spending £140 having both shafts and props polished as part of it's spruce up.
The only thing I miss is the ability to beach the boat as we did with the Targa 35 a few times on tidal moorings.
Henry
On the Princess costs have been zero. Actually that's not strictly true. Currently spending £140 having both shafts and props polished as part of it's spruce up.
The only thing I miss is the ability to beach the boat as we did with the Targa 35 a few times on tidal moorings.
Henry
tinkicker0
Well-Known Member
Can't get me head round those that think outdrives are complex and expensive. They are extremely simple bevel drives that dangle in the water.
The issues that surround them are simply bad design compromises. I do all my own work on mine and it's not rocket science.
4 years worth on an alpha gen2
2x sets of bellows - about 3 hours work a time, albeit in cramped conditions.
1x shift cable. 2 hours maybe.
1x water hose.
2x impellors
1x pair of hardy spicer joints.
1x upper gearcase shaft seal.
1x upper bevel gear bearing shimmed and changed as a matter of course while the top was off. (FOD inclusions on outer track, not wear).
Lube change every year.
Cost? Maybe an average of £150 quid a year on parts. Note that many of these parts were not changed "on condition" but as a matter of course whilst the thing was in bits. They were still serviceable, but not as new.
Mind you, given the choice and the wallet to make that choice, I'd go for shafts if it was in saltwater.
The issues that surround them are simply bad design compromises. I do all my own work on mine and it's not rocket science.
4 years worth on an alpha gen2
2x sets of bellows - about 3 hours work a time, albeit in cramped conditions.
1x shift cable. 2 hours maybe.
1x water hose.
2x impellors
1x pair of hardy spicer joints.
1x upper gearcase shaft seal.
1x upper bevel gear bearing shimmed and changed as a matter of course while the top was off. (FOD inclusions on outer track, not wear).
Lube change every year.
Cost? Maybe an average of £150 quid a year on parts. Note that many of these parts were not changed "on condition" but as a matter of course whilst the thing was in bits. They were still serviceable, but not as new.
Mind you, given the choice and the wallet to make that choice, I'd go for shafts if it was in saltwater.
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martin
Well-Known Member
Shaft newbie
All previous boats have been Mercruiser outdrives and never had a problem except on a brand new SealineF33 which had Volvo outdrives that had to be replaced in the first year. The Merc's had several run ins with unfriendly fishing line but it didnt seem to damage anything...
This is my first boat with shafts and I have to say am horrified at increased fuel costs..I have to say it has made me think twice about "popping out" for a quick cruise..
That said, i am very happy to hear that i seem to have escaped my brush with the devil..... that is until i hit something submergered... I made a general enquiry and was staggered to hear the replacement cost of the props.. Hopefully the need will never arise...
All previous boats have been Mercruiser outdrives and never had a problem except on a brand new SealineF33 which had Volvo outdrives that had to be replaced in the first year. The Merc's had several run ins with unfriendly fishing line but it didnt seem to damage anything...
This is my first boat with shafts and I have to say am horrified at increased fuel costs..I have to say it has made me think twice about "popping out" for a quick cruise..
That said, i am very happy to hear that i seem to have escaped my brush with the devil..... that is until i hit something submergered... I made a general enquiry and was staggered to hear the replacement cost of the props.. Hopefully the need will never arise...
oldgit
Well-Known Member
"This is my first boat with shafts and I have to say am horrified at increased fuel costs."
Going from outdanglers to nice simple props recently,was a bit concerned about the difference in fuel consumption between the two.However,for my type of displacement boating,fuel consumption(about 150 hours so far on this boat) has proved to be little worse than on my old tub.
This is despite moving up to a bigger and heavier boat.
Going from outdanglers to nice simple props recently,was a bit concerned about the difference in fuel consumption between the two.However,for my type of displacement boating,fuel consumption(about 150 hours so far on this boat) has proved to be little worse than on my old tub.
This is despite moving up to a bigger and heavier boat.
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martin
Well-Known Member
Jealous
Well i can see the simplicity angle has its merits but my fuel bill for a recent return trip from St Kats to Medway was off the chart...so much so that i even resorted to reading the manual and downloading the engine specs...I did day it was shocking!
I am currently arranging a rematch after having her hauled out and hull scrubbed as the only explanation is that i carried an underwater forest all the whole way!!
Well i can see the simplicity angle has its merits but my fuel bill for a recent return trip from St Kats to Medway was off the chart...so much so that i even resorted to reading the manual and downloading the engine specs...I did day it was shocking!
I am currently arranging a rematch after having her hauled out and hull scrubbed as the only explanation is that i carried an underwater forest all the whole way!!
MapisM
Well-Known Member
I'm not surprised at all to hear that.
The inherent inefficiency of shafts (vs. outdrives, outboards or surface transmission) is only related their use with planing hulls.
In displacement hulls, shafts are the only logical choice.
The only D boats which have other than shafts are the very small ones, where outboards have their place only for practicality (not efficiency) reasons.
henryf
Well-Known Member
I have to say I don't think our shaft driven Princess P42 with a pair of D6 435hp engines is particularly thirsty. Yes, if you are dragging round a load of weed you will be tearing up money (we once stopped off in Cowes for a quick Sealift prior to a cross channel jaunt to France and the Channel Islands and I think it more than paid for it's self in that one trip.
It is very easy to find the sweet spot whereby fuel burn is at it's lowest. I haven't ever measured it but I would guess somewhere around the 0.8 g/mile mark. Certainly under 1 gallon per mile.
Reading other posts on here it would suggest prop life is greatly extended on shafts as well. For some outdrive users it looks like props are a bi-annual expense !
Henry
It is very easy to find the sweet spot whereby fuel burn is at it's lowest. I haven't ever measured it but I would guess somewhere around the 0.8 g/mile mark. Certainly under 1 gallon per mile.
Reading other posts on here it would suggest prop life is greatly extended on shafts as well. For some outdrive users it looks like props are a bi-annual expense !
Henry
Nautorius
Well-Known Member
Ok,
All of my MOBOS were outdrives and I was located where there was good support. However I did have a nightmare leg on a New Chapparal that never was reliable (and never got fixed)
Outdrives are great if you have a good guy looking after them (Col, Volvo paul). However where I now live (MED) lift outs and hard standing are expensive and local support minimal. As a result I would only have a shaft MOBO.
Currently have a Shaft Sail boat which has had the Yanmar Gearbox go at only 850hours! Nightmare as no new ones in stock...but that is just bad luck. However have a great local engineer and a Diver who scrubs the bum and relaces anodes to save lift out! Given emergency lifts are limited in Gib it is best to have a shaft boat...about 43ft and twin Volvos in her. maybe time to get rid of those flappy things after 2 1/2 years.
Paul