Using an outboard for tender and yacht auxilliery

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I have acquired a 10ft inflatable tender and am now looking for an engine. My 28ft Westerley is fitted with an outboard bracket. Today the inboard yanmar packed up, though not terminal. Question! If i buy a 4hp 4 stroke and fit it to the outboard bracket when not on the tender, will it get me home if the yanmar fails again? Do i need a longshaft? Any advice please. keep it simple , I'm new to all this. Thanks
 
Your Westerley is a lot heavier than my Quarter Tonner , but even so my 4Hp Mariner Sailmate gives me 5 knots on a good day. If a there is a bit of a swell the only disadvantage of having a transom mounuted outboard is that occasionally the motor will become an egg whisk and lose drive.
I have been impressed with the fuel economy of my small outboard.
I think that as an auxiliary your outboard is well up to the job if the Yanmar packs up !
Hope this helps.
 
Yes we took a Westerly Berwick quite a way down the Little Russell towards St Peter Port with a small outboard on the inflatable lashed alongside. I forget now if it was a 2hp Yamaha or a Seagull Featherweight. It was flat calm of course which is why we were not sailing.

The shaft length you need depends on the height of the bracket. Typically standard shaft outboards are designed for a transom height of around 15" and long-shaft models for 20" but it may be advantageous in anything other than calm water to immerse the prop a little deeper than intended for the reasons already given. There is some variation between makes so check the specified transom height rather than the description standard or long shaft.

You are unlikely to want a long shaft for your tender!. If immersed too deep they can be difficult to start due to back pressure on the exhaust, but that may not be quite such an issue with a 4 stroke as it is with a 2 stroke.
Also if you are landing on a hard, a slipway or a beach a long shaft will hit the bottom a lot sooner!
 
1. That's interesting, VicS. I've heard of that being done and often wondered how that practicable it was. Did you have someone in the tender all the time? Who did the steeering?

2. To answer the original question -

After an inboard engine failure on my Twister I moved her from her berth to the club crane to have the engine lifted out, and back again to her berth, using a Yamaha 2B mounted on a plank temporarily bolted to the aft pulpit. This moved the boat at a good speed. In fact she went too fast and it was difficult to reach down over the steeply sloping transom to control the outboard whilst steering.

The big problem using it in a seaway would be that the outboard could easily get swamped by a following sea.

Don't laugh, but have you considered an oar or a yuloh?
 
[ QUOTE ]
That's interesting, VicS

[/ QUOTE ] Yes it worked fine. Yes someone was in the dinghy ~~~~ me! Steering was with the main rudder. I cant remember now what distance we covered but we had friends already in St.P.P and one of them came to meet us so we ended up with an inflatable + o/b lashed to each side.
 
Some tips on towing with tender lashed alongside:

- get all lines, including springs, set up nice and tight.
- have the bow of the tender angled slightly inwards (towards the mother 'ship')
- the stern of the tender should poke out astern of the mother ship's rudder. This greatly improves manoevrability.
- it goes without saying that you need good fendering, and that it's a technique for calm conditions only
- keep fingers out of the gap between the two vessels.
- most steering is done by the mother ship, with the tender just providing power
- the crew in the tender can assist with close quarters steering

The system works well.
 
Last year I was coming into Portsmouth harbour and due to a delay getting there was fighting the outgoing spring tide. My 12hp Yanmar inboard couldnt push me hard enough and I got half way through the entrance and started going backwards. After a couple of tries I gave up rather embarassingly. Then I remembered I have a cantilevered outboard bracket on the stern to which I fixed my 4hp mariner to and it worked brilliantly. Up to then I had never used it but it certainly proved its worth as a back up on this occasion.
 
It will be worth getting a saildrive prop for best performance with your yacht although dinghy speed may be slower.

When rudder became unserviceable have motor sailed home using outboard for steering.
 
I have a Snapdragon 24 with an OB bracket on the back and our Tohatsu 3.5 has got us out of potential trouble on a number of occasions, so I can see no reason why your 4HP shouldn't be a very useful backup. However, I wouldn't rely on it as an everyday thing for the following reasons:

1. Your dinghy wants a short shaft, while the yacht wants a long shaft. Short shaft on the yacht will tend to lift out of the water in swell, which won't do it too much damage on an occasional basis, but isn't recommended. Even a long shaft will do this, but less. A long shaft on an inflatable dinghy will try and fold it in half (bottom in) if you use too much grunt, like punching a tide.

2. With the OB behind the rudder, manouvering at low speed in tight spaces can be interesting 'cos you've no prop wash over the rudder. If you steer with the OB, you're bending over the transom, so you can't see the front of the boat...

3. 4HP just isn't enough when the elements conspire against you. I once drove up Portsmouth harbour into the teeth of an F6-7 on the outboard 'cos the inboard was sulking. I won't forget trying to dodge the fleets of racing dinghies in a hurry /forums/images/graemlins/tongue.gif

Stemar's recommendation: Fix the Inboard - it'll always be better than the right OB for your boat, let alone one you could use on your dinghy, get the right OB for your dinghy and add a bracket something like this so if the inboard throws a tantrum, you've got a get-me-home.
 
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