Outboard size for emergencies

Tranona said:
Simple answer o that problem is to invest in a rope cutter.
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I am not particularly bothered about ropes round the prop - I doubt if my 1GM10 would have the oomph to drive a rope cutter through anything substantial anyway, even if there was room to fit one. I am far more concerned about a rope going under the boat and slipping up between rudder and hull. It's happened once and it was a real sod.
 
JumbleDuck said:
I am not particularly bothered about ropes round the prop - I doubt if my 1GM10 would have the oomph to drive a rope cutter through anything substantial anyway, even if there was room to fit one. I am far more concerned about a rope going under the boat and slipping up between rudder and hull. It's happened once and it was a real sod.
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Well, it will. At least my iGM had no problem cutting the kind of rope use for potlines and fishing nets. Found traces of it round the cutter just about every year and felt the bumps when it did its job.

If you want to know what can happen if you do pick up a net with a prop in an aperture like yours, find a copy off the June 1988 (from memory) PBO and you will find an article by me explaining all. Fee went a long way to paying for the cutter and explains why i am a fan of such devices.
 
Tranona said:
Well, it will. At least my iGM had no problem cutting the kind of rope use for potlines and fishing nets. Found traces of it round the cutter just about every year and felt the bumps when it did its job.

If you want to know what can happen if you do pick up a net with a prop in an aperture like yours, find a copy off the June 1988 (from memory) PBO and you will find an article by me explaining all. Fee went a long way to paying for the cutter and explains why i am a fan of such devices.
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I'll think about it. I suspect the sharp-circular-blade type would be more a 1GMA10's thing than the blades-passing-each-other type. The main problem is that I have about 3/4" of shaft free between cutless gland and prop, and I need to leave some/most of that free for the water supply to the gland.
 
ostell said:
+1, especially when trying to get on the mooring and the bow is tied on.
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Being moored by the rudder on a bouncy day is slightly less than my idea of fun. My crew is trained to tell me if the mooring and pickup buoys ever start moving back along opposite sides of the boat ...
 
The cutless is a bearing not a gland. It can be mounted in the deadwood or on a P bracket.
JumbleDuck said:
I'll think about it. I suspect the sharp-circular-blade type would be more a 1GMA10's thing than the blades-passing-each-other type. The main problem is that I have about 3/4" of shaft free between cutless gland and prop, and I need to leave some/most of that free for the water supply to the gland.
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JumbleDuck said:
The main problem is that I have about 3/4" of shaft free between cutless gland and prop
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The Spurs cutter (and probably others) is available with a spacer to fit between the gearbox output flange and the shaft coupling, which shifts it back just far enough to fit the cutter. Obviously this requires sufficient clearance from the rudder and, inside, between the coupling and the stern gland.

Pete
 
On our previous boat - 27' Albin Vega - I fitted a hinged 4-step boarding ladder onto the stern and around the bottom tread of this I built-up a 1.5" timber board about 6" x 8"; with a rope from this to the pushpit rail the lower half of the ladder could be suspended to project horizontally and with our 3.3hp Mercury outboard clamped onto it, we could make 2.5-3 knots in flat water. We needed to use it in anger twice and it worked on both occasions. I'd thought it might need something to hold the motor down, but self-weight seemed sufficient.
 
Jissel's only 24ft but, on passage, the dinghy outboard, a Tohatsu 3.5 short shaft, lives on a lifting bracket on the transom. The bracket keeps the OB out of the water in the up position, gets it low enough that the prop's below the bottom of the boat when down.

It will push her along at 3-4 knots in calm conditions. When the main engine didn't want to play coming into Portsmouth in a good F6, it got us in, though I wouldn't want to try and punch the tide as well as the wind, and getting the bow back into the wind after dodging a sailing dinghy was interesting.
 
One the little rules in my head when buying a second hand boat with an inboard was to avoid boats that have outboard brackets on them because they are a sure sign of a boat with an unreliable engine

Now I have changed my mind entirely and regard the presence of a bracket as a sailor who recognises that the most likely cause of a failure in the mechanical propulsion system of the boat is not engine or gearbox failure but creel pot marker entrapment.

For me, an outboard bracket on the back of a boat with an inboard is a positive thing and I know that it will save me having to fit one

sadly, Centaur 2, has no bracket for the Tohastsu

last time I swapped some DVDs for one that was stout but seized

so I am open to suggestions about sourcing a stout one

there are few things in life more worrying than an under-engineered outboard bracket.

Very willing to swap free downloads that are already free

D
 
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Must admit I keep meaning to test whether my dinghy outboard will clamp onto the edge of the kedge locker in Ariam's swim platform. It's the perfect height above the water, but has quite a steep tumblehome which will complicate matters. It's only a 2hp outboard, but that could still push me into a berth on a calm day.

Pete
 
I have a 3.5hp Tohatsu two-stroke that is a long shaft. It was given to me and it is my intention to have it as a spare on my Jaguar 23 and use it on the Avon inflatable as well. If running it 'deep' causes problems I'll extend the wooden o/b mount on flubber upwards some 6 or 8 inches. Not ideal I realise, but worth a go.
 
JumbleDuck said:
I'll think about it. I suspect the sharp-circular-blade type would be more a 1GMA10's thing than the blades-passing-each-other type. The main problem is that I have about 3/4" of shaft free between cutless gland and prop, and I need to leave some/most of that free for the water supply to the gland.
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Disc cutters are a waste of time in your situation as it is rope balling up in the aperture that is the problem and you need a scissors cutter such as the Ambassador Stripper (which is what I have) to deal with that.

You need to move the prop back around 30-35mm to make space for it. If you can do that and maintain clearance for the prop then use a spacer in the coupling.

Details on www.ropestripper.com. You need an AM5 model with 2 or 3 blades depending on your prop.
 
fredrussell said:
I have a 3.5hp Tohatsu two-stroke that is a long shaft. It was given to me and it is my intention to have it as a spare on my Jaguar 23 and use it on the Avon inflatable as well. If running it 'deep' causes problems I'll extend the wooden o/b mount on flubber upwards some 6 or 8 inches. Not ideal I realise, but worth a go.
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The minimum distance is 5" higher - but you will find the motor very unbalanced like that. As I said earlier there are sound reasons why the correct motor should be used.

The compromise of having a proper short shaft for a dinghy and a low mounting bracket to use it on the yacht is the least worst compromise - assuming the primary use is for the tender.
 
Just out of interest, what would be the downsides or risks of using a long shaft OB on an inflatable? I realise I run the risk of OB bottoming out as I near land and the pin shearing (or worse), but are there more serious concerns?
 
fredrussell said:
Just out of interest, what would be the downsides or risks of using a long shaft OB on an inflatable? I realise I run the risk of OB bottoming out as I near land and the pin shearing (or worse), but are there more serious concerns?
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Nothing really just very awkward and a pain in the backside.

Unless you are elderly or infirm lashing your dinghy alongside with a standard shaft motor is a good fix. If the wind is blowing you can sail.
 
fredrussell said:
Just out of interest, what would be the downsides or risks of using a long shaft OB on an inflatable? I realise I run the risk of OB bottoming out as I near land and the pin shearing (or worse), but are there more serious concerns?
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Yes, the centre of thrust is lower and usually has the effect of raising the bow. When turning it can also upset the trim. On some motors you may have difficulty in starting because thee motor is too low in the water causing back pressure.
 
doug748 said:
Nothing really just very awkward and a pain in the backside.

Unless you are elderly or infirm lashing your dinghy alongside with a standard shaft motor is a good fix. If the wind is blowing you can sail.
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As a plan B in the event of engine failure or prop wrapping mounting the outboard on a bracket on the stern of the main yachts is, I believe, more seamanlike and maneuverable than than breasting a flubber up.

As I sail alone the logistics of such an operation would be most edifying

How would you propose making such a thing work when sailing solo

however, we all have to have a plan B - the bracket is a beyter plan B for those who sail solo.
 
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