Long Shaft OB on Inflatable

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johnjfrake

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I have a Seagull Kingfisher Long Shaft to power my Folksong 25. Would like to carry a small Dinghy as intend to do more anchoring and less Marina than has been the case in past years. Don't have space for 2 outboards so does anyone have any ideas on adapting a long shaft OB to a small inflatable ( not purchased yet).

Thanks and regards

john
 
No. Won't work. Not only is a long shaft outboard too cumbersome, but on an inflateble it will be immersed too far and you will have difficulty in starting and the prop will ground in shallow water. Standard shaft are for 15 inch transoms and long shaft 21 inch.

Practise your rowing!
 
My boat is similar type and I put 2hp outboard on a bit of plank on the pushpit. Is something similar possible ? To be honest, I find storing the inflatable itself more of a nuisance.
 
As Tranona says really not suitable for a small inflatable.

Older smaller engines (40+ etc) could be fitted with a depth adjusting collar but not suitable for these larger models .... any way not really a practical proposition to keep fitting and removing it.

Suggest that if Seagulls "float your boat" you keep an eye out for a decent Featherweight/ Model 45
They actually have a shorter shaft than the standard making them ideal for a small dinghy (13" transom height) and easier to stow. I stow one in a 19ft Sea Wych!

I agree with Spuddy. Stowing an inflatable is more difficult ... in fact I bought a nice , barely use Avon about 9 or 10 years go ...not yet used it!
 
And if you do buy an inflatable get one with some kind of a keel, preferably inflatable. After 15 years of dogged perseverance with an old French inflatable I finally bought a new one withe an infl. keel this year. I still can't believe how much more satisfying it is to row.
I agree with others re not using long shaft.
 
I think the idea is on the right lines but not with your Kingfisher. I don't have to tell you what a heavy awkward lump that engine is.
I once used a similar boat for half a season with a longshaft 2hp Seagull and used it on the dinghy as well. It just about moved the Folkboat, and come to think of it, was not grand on the tender. However it worked; in sheltered waters.
If you could wangle yourself a light 4/5 hp modern 2 stroke unit you could be in business. Yamaha Malta perhaps?
 
Well, there is a fairly standard method of converting a Longshaft Seagull to a Standard Shaft (without resorting to a hacksaw), and that's to fit a suitable collar between the transom clamp and the engine block. I've seen collars made from old radiator hose, and even aluminium pipe - two halfs held together with Jubilee clips ...

But if memory serves, the Kingfisher weights around 55 lbs - so you might want to think about a lighter engine for an inflatable ?
 
If you did ever think about a long shaft outboard on a dinghy, I'd look at a Tohatsu 3.5 or the equivalent mercury/mariner. I used to use one on a 26ft quarter tonner and then put it on the back of the dinghy and go ashore with it no problems. Always started and didn't have problems with it on the dinghy.
 
johnjfrake said:
I have a Seagull Kingfisher Long Shaft to power my Folksong 25. Would like to carry a small Dinghy as intend to do more anchoring and less Marina than has been the case in past years. Don't have space for 2 outboards so does anyone have any ideas on adapting a long shaft OB to a small inflatable ( not purchased yet).

Thanks and regards

john
Click to expand...

A longshaft 4HP Mariner on a Wetline has worked fine for me for four or five years. - no idea about the exhaust on your seagull though.

The only disadvantage for me is the likeleyhood of hitting the bottom with the prop when beaching if I don't take care.
 
I have a Yamaha 2hp 2-stroke, it's been with me since 1987 and survived at least 3 dunkings ! - either by inflatable being flipped in a gale or losing air through sand in the valves ( both my fault, being careless in gale-induced fatigue ) - a fresh water wash & attention to the bearings was all that was required.

It's very light too, and stows easily clamped to a wooden pad on the pushpit.

As for inflatables, I cannot urge this too strongly !

Go for a 'round tail' type, they're MUCH easier to stow - I have that problem too, I keep my Zodiac 240 under the cockpit as I don't have an inboard engine, but werever one stows the thing it's much less hassle than a solid transom - and one can get outboard brackets from the makers.

When investigating buying a new inflatable last summer, I found Piplers of Poole were doing a good deal on 'round tail' jobs.

I'm not connected in any way, just pleased with their service.

Re. Outboards I find a 2hp 2 stroke plenty, your main problem may well be finding someone willing to part with one !

I tried using the 'main' 5hp standard shaft outboard on the tender about once; far too heavy, and if one has a mishap that's the cruiser's engine stuffed !

A chum had this happen to him, although very experienced he managed to hit something underwater, which tore the controls out of his hand ( and he's a strong bloke, I wouldn't choose to arm wrestle with him ! ) turned the 'big' engine at 90 degrees, capsizing his 9' tender -the engine then fell off, awaiting a couple of tides until recovery which didn't improve it; chum was luckily spotted and recovered by a rescue boat, which is a whole different topic, he was wearing a lifejacket but in for a very long swim if not rescued - the boat had buoyancy but unlike racing dinghies, tenders are nigh on impossible to recover; if this had been at night...
 
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electrosys said:
Well, there is a fairly standard method of converting a Longshaft Seagull to a Standard Shaft (without resorting to a hacksaw), and that's to fit a suitable collar between the transom clamp and the engine block. I've seen collars made from old radiator hose, and even aluminium pipe - two halfs held together with Jubilee clips ...

But if memory serves, the Kingfisher weights around 55 lbs - so you might want to think about a lighter engine for an inflatable ?
Click to expand...

Pretty sure you can't do that on a Kingfisher as it has a different clamp arrangement. Anyway raising the power head by 6" which make the motor hopelessly top heavy. The collar was intended to just raise the head about 2" when using a 40+ on an Avon.
 
My memory might be failing me as it is 30 years since I worked for Seagull and the Kingfisher was still in development. However, pretty sure that the leg is a larger diameter below the clamp so can't be raised.

Anyway, the point is that the engine, particularly in long shaft form is unsuitable for use on an inflatable. The short shaft would work on a larger inflatable with a harf transom, but performance would be poor because of the gear ratio and large fine pitched prop.
 
Not the least of your problems on a small inflateable is that the engine is very likely to tip the dinghy A... over T.. when you step out of it. Ask me how I know:eek:
I second the 2HP 2-stroke, Yamaha, Mariner ...
 
johnjfrake said:
I have a Seagull Kingfisher Long Shaft to power my Folksong 25. Would like to carry a small Dinghy as intend to do more anchoring and less Marina than has been the case in past years. Don't have space for 2 outboards so does anyone have any ideas on adapting a long shaft OB to a small inflatable ( not purchased yet).

Thanks and regards

john
Click to expand...

Many years ago used a longshaft Seagull Century as both main boat propulsion and occasionally on a small Avon Redstart inflatable. On main boat with leg correctly immersed engine a first pull starter every time. On inflatable starting more difficult but would always start, but you could not give much throttle before the thrust started deforming the inflatable - logical because of long lever arm to prop. Obviously had to row last bit to beach.

Only ever used o/b on inflatable if I had a very long row to windward in prospect! On a small Avon a water or fuel can left full in the bows was also advisable if you wanted to leave the dinghy floating unattended with o/b leg raised...
 
First of all thanks to all for the replies. I can see that this isn't a runner short of extending the transom mount upwards by 6" or modifying the OB Clamp and then adding a 15 Kilo counter weight to the front of the dinghy to stop it flipping. I must admit that I may not carry a dingy at all, they are bulky and I haven't used one in 3 years and there isn't a lot of room on the boat!
 
Tranona said:
My memory might be failing me as it is 30 years since I worked for Seagull and the Kingfisher was still in development. However, pretty sure that the leg is a larger diameter below the clamp so can't be raised.
Click to expand...
Yes it is (like many Seagull long-shafts, including my pair of Silver Century Plus's - damned fine engines, BTW), but it can still be raised, that is, if you're so minded.
Assuming that the clamp is a bog-standard Seagull affair, the easiest method is to make a custom drive-shaft clamp. In the past I've used a small lump of elm. The 'cross' hole (to take the quick-release pin) is best made over-size to take a s/s pipe, and then fit the pin through the pipe. It locates into the clamp lugs better that way and makes for a stronger fitting.

The other method is to fit a transom 'riser', to raise the whole caboodle by the desired amount. I've never done this myself, but have heard of it being done.

But - these various field-fixes are only really suitable for a rigid hull appropriate to the weight of the engine. Not really suitable for an inflatable - at least I wouldn't try it.

BTW - did you know that some people (warm-water people !) even race Seagull engines - wacky or what ?
 
Long Shaft OB on Inflatable Reply to Thread

I met one of the racers when buying a remote fuel connection and throttle/gear linkage plate for my Kingfisher. Its not a cheap sport by all accounts. Forgot to ask what kind of boat you use and how do you handicap, if indeed they do.
 
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