Outdrive Aversion - is it justified?

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AHoy2

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I am considering a change of boat and found that, in the 32 to 34 foot LOA twin diesel range, my choice is considerably limited if I restrict myself to boats with shaft drive (my preference). The requirement is for a boat that will be afloat/used all year round for coastal and cross channel family cruising, days out and fishing sorties (total around 150 to 200 engine hours per year). It will definitely not be just fair weather summer use.

I have so far excluded outdrive powered boats mainly due to the seemingly high maintenance levels and costs together with dubious reliability compared to shaft drive. This view applies to not just the drive unit but all the associated ancillaries. In addition shaft drive models, in general, seem to get the nod in terms of handling and sea keeping ability.

Is my aversion justified or am I excluding some good boats because of bias?

Note: I am not looking for recommendations on specific boats, although suggestions on outdrive contenders would assist. Definitely no canvas top sports models though.

TIA.
AHoy2
 
AHoy2 said:
I am considering a change of boat and found that, in the 32 to 34 foot LOA twin diesel range, my choice is considerably limited if I restrict myself to boats with shaft drive (my preference). The requirement is for a boat that will be afloat/used all year round for coastal and cross channel family cruising, days out and fishing sorties (total around 150 to 200 engine hours per year). It will definitely not be just fair weather summer use.

I have so far excluded outdrive powered boats mainly due to the seemingly high maintenance levels and costs together with dubious reliability compared to shaft drive. This view applies to not just the drive unit but all the associated ancillaries. In addition shaft drive models, in general, seem to get the nod in terms of handling and sea keeping ability.

Is my aversion justified or am I excluding some good boats because of bias?

Note: I am not looking for recommendations on specific boats, although suggestions on outdrive contenders would assist. Definitely no canvas top sports models though.

TIA.
AHoy2
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Limited knowledge here but
Engines are smaller on strendrives installations, as such:
They can be easier to get to and work on.
They can give reduced saloon noise and increase living area because of engine location and size.
I suppose and I may be wrong they may use less fuel/mile.
There may be occasions where you want to and can reduce your draft.
I think you have covered the downsides
 
I have original Volvo 280 legs on a 1981 boat. I spend about £1,000 every 2 years on a lift out and leg service (Thames prices). Were I to look for another boat I would prefer shafts because of this cost; sadly my model was never made with shafts.
They tell me that because the hull shape is 'perfect' they are faster and more economical than shaft drives but I dont know the science of all that.
I would not say we have had any troubles with the outdrives, and when tidal I feel very re-assured that I can lift a leg and remove prop fouling (which is quite a common occurence on the Thames tideway).
We do however have the boat and the accommodation that we wanted.
 
Outdrives

Like most things in boating the choice between shafts and drives is all about compromise.
I share your preference for shafts and hated drives but ended up with a sportscruiser with twin drives because that is what was available in our size range and it gave the best in terms of accomodation cos the engines are right at the back.

I have found the main benefits of drives over shafts (my last boat was twin shafts) to be:
- Better fuel economy
- Better performance (speed)
- Directional thrust (makes up some of the shortfall in not having shafts for manouverability)
- Easy access to props
- Ability to reduce draught in shallow waters
- Better use of space i.e. room forward for the accomodation and engine work done in the cockpit as opposed to the saloon (no oil on the soft furnishings so not in trouble for that)!

With your projected hours of use the fuel economy point may go some way to defraying the maintenance costs for drives.

Having had drives again for three years or so and having done a lot more maintenance work myself the mystery has gone and I know what needs to be done. Maintenance is the key i.e. change the bellows every couple of years and change/check the oil in the interim to catch any water ingress problem early (we have had ingress but now resolved and no damage because of the maintenance schedule). That said things can be expensive e.g. replacement rams but if you look around you can makes savings (I had a ram refurbished for a fraction of the cost of a new one)

I think it is also easy to forget about the dificulties that can be associated with changing cutlass bearings and getting access to stern glands with shafts.

Overall, I would say don't exclude drives as an option. There are pros and cons and IMHO they should be considered in the overall context of what the whole boat offers for your anticipated use.
 
I have a single outdrive. Low speed handling and control is appalling. If I had a choice, it would be shafts for me.
High maintenence? can be, depends on attitude. I'm pretty anal about taking off the drive every end of season at lay up time, greasing and checking everything, replacing bellows ect and touching up the paint.

Other boats on chocks nearby do not appear to have anything done to them and they go back into the water without problems.
Indeed many do not even bother to have their boats lifted outduring the winter.

As with all things, you have to say to yourself "is blissfull neglect worth the final bang"?
 
Main differance

Shaft drive boats tend to have the engines more centrally in the boat, and tend to need more power to move them, so need bigger engines.
They need these as they have to literally push them selves onto the plain, or if a non plaining vessel they push the water out the way constantly, hence the large wakes from displacement vessels and vessels not quite on the plain.
They tend to be heavier boats, this means you have the extra stability that weight will give you in a rough sea but also means there throw around ability is less, I mean by this that they do not lean over as much on a turn as an out drive boat will, ie less likely to spill "the Gin and tonic, don't you know" [ Imagen posh voice there.]

Out drives have the engines further back near the stern, so all the weight is at the back but also where the power is.This means they need less powerful engines, so are lighter boats. They have lighter bows , they plain by pushing the bow out the water then when enough speed is gained the stern slides onto the plain. Hence why you can loose visibility easily on a sports cruiser before she climes onto the plaining. PS trim tabs down can help with this.
The lighter bows, this does depend on the type of boat , some are better than others, can get bounced around in a rough sea, but you do have the advantage of quick response time to a helm request, so making it better to steer her around waves in a rough sea, "sport means exercise does it not "
They tend to have more available space down below for accommodation due to the engine position.

It can mean the wind will move the bow more easily but this happens on shaft or outdrive sports type boats.
 
I have an aversion to outdrives as well, even though I run one. I keep mine dry berthed, so after 3yrs and 500hrs use it's as good as new

Props.jpg


The thought of keeping all that expensive stuff in the water all the time, fills me with dread. If I was going to keep a boat in the water, it'd have to be shafts. I know what I'd save on maintenance I'd probably spend on fuel, but it's a psychological thing with me - I'm nuts!
 
Problems with outdrives are very age related,fine when new and you are able to throw your credit card down onto the desk of your Volvo Penta dealer and say ..do whatever needs doing chief and let me know when the boat is back in the water.
As time passes and the subsequent owners have less wonga,stuff either does not get done on time or... at all ...and outdrives demand to be fettled on a regular basis or they will turn round and bite you big time.
A leak in the drive rubber may only just be a rebuilt U/J but if it gets into the transom bearing its the engine out and all that entails.
Rams are hundreds of pounds each,if you have early stuff like mine they are .........................£775 + vat each god help you if you need 4.
The rams will also corrode if given half a chance.....no chance of rebuild there,and check out the price of the 8 hoses you will need in any twin installation.
To sum up legs are OK on soapdishes or when fairly new,having said that the little boat yard out side my front door has had a couple of virtually new boats with SX drives suffering from problems including corrosion.
If you are a DIY man the prospect of pulling off two legs every other year,cleaning in all the nooks and crannies,then having to A/F the blimming things in what costs more than gold dust will soon lose its attraction.
Good Luck.
 
tinkicker0 said:
I have a single outdrive. Low speed handling and control is appalling. If I had a choice, it would be shafts for me.
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Tinkicker, there is a simple low cost solution to your low speed handling problems. Fit a mild steel epoxy coated skeg under the hull ahead of the outdrive. Make it about 15 inches long and about 9 inches deep. Adjust the size according to boat speed. This acts as a fixed rudder and stabilises the hull direction at low speed.
As long as it is not to big it will have no affect at high speed. If it does simply cut the size down with an angle grinder.
This is not theory!!! I have done it on two boats and the difference is phenomenal!
 
oldgit said:
Problems with outdrives are very age related,fine when new and you are able to throw your credit card down onto the desk of your Volvo Penta dealer and say ..do whatever needs doing chief and let me know when the boat is back in the water.
As time passes and the subsequent owners have less wonga, stuff either does not get done on time or... at all ...and outdrives demand to be fettled on a regular basis or they will turn round and bite you big time.
Click to expand...

Nah, They are easy to maintain, get the Volvo workshop manual and learn all about them. All parts other than casings, gears and shafts are avaiilable from seals and bearings suppliers. Example: Bearing ahead of UJ, plus two lip seals. £12. (Same quality as Volvo use because obviously they don't make their own).
There are also enough drives around to ensure a ready supply of cheap secondhand parts.

Like any precision gearbox they need a bit of care. Most are totally ignored, hence the bad reputation. A blast with the pressure washer and a spray of antifouling makes basic care very easy. (Cheap compressor £99 cheap anti-foul gun £11)

Funnily enough I prefer shafts but with a change of boat type I have to go back to drives but I can live with that!
 
Thinking about Geoffs and his dry berthed boat. How about a bag to place under the drive when it is not being used but still afloat. Once in place the water is pumped out and the leg is left to dry. Why not?
 
[QUOTE I spend about £1,000 every 2 years on a lift out and leg service (Thames prices).. . I would prefer shafts because of this cost QUOTE]

IMHO £500 is a fair price for annual lift ashore, antifoul and engine service without DIY input wherever you are and whatever drives the boat.
 
PFC said:
Thinking about Geoffs and his dry berthed boat. How about a bag to place under the drive when it is not being used but still afloat. Once in place the water is pumped out and the leg is left to dry. Why not?
Click to expand...

Why not indeed - on a larger scale, that is how the sea pen dry berthing system works:

http://www.seapen.com.au

Cheers
Jimmy
 
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Tidnock said:
Those Targa offshore boats sold by Wessex Marine are all outdrive aren't they??
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Yes, and there's quite a number of other very seaworthy outdrive boats around.

However, our leg is absorbing lots of cash this year - the fuel consump - v - maint. cost are making me tend to go the shaft route next time. Ah, but then there's the FUN factor of outdrives - decisions, decisions!!
 
You are having some nasty bills John, but should that put you off all outdrive boats? Its not like you are having this issue every year.. in fact its just this one isnt it?And your problems are not common to all outdrives.
But have you managed to discover if the drying berth is causing of the problem- ie , its a known issue? Hows about a tender, and a mooring. Maybe lease the tidal berth?
 
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