Outboard question

[tinstaafl]

Thinking of plonking a 8-ish HP outboard on the back of our boat for use as auxiliary propulsion.

How do I know whether I need a short or long shaft? I presume that everything's ok as long as the prop is below the bottom of the hull. It's unlikely to get up to planing speeds I would imagine /forums/images/graemlins/smile.gif

tinstaafl

 

[Howardnp]

If all you want it for is aux on the Loch then 8hp is probably more than big enough. As a get you home unit go for something a bit smaller and lighter. remember you're adding more weight on the back. Put some weights there equivalent to an aux motor and see what happens with the attitude of the boat.
Just had to fit wedges on the main outboard on a sportboat to keep the bows down because of the weight at the back.

 

[tinstaafl]

[ QUOTE ]
If all you want it for is aux on the Loch then 8hp is probably more than big enough. As a get you home unit go for something a bit smaller and lighter. remember you're adding more weight on the back. Put some weights there equivalent to an aux motor and see what happens with the attitude of the boat.
Just had to fit wedges on the main outboard on a sportboat to keep the bows down because of the weight at the back.

[/ QUOTE ]

Hmm, was thinking about stashing it in our central locker under the floor actually so although the weight will be the same, obviously, it won't be hanging off the back of the boat.

Also, it's not really for the loch, it's because we may move to the sea in a year or two - Clyde to be exact. Thx for the input though /forums/images/graemlins/smile.gif

tinstaafl

 

[Alistairr]

I think probably short, but it will depend on where you mount the outboard bracket on the transom.

But DO think about the weight issue, 8hp is a big heavy motor, not easily handled out of a locker, over the rear of the boat and trying to mount onto an outboard bracket on the transon, all that in heavy seas that have caused you main engine to fail!!!! Not Easy.

I have been looking at the Yamaha 4hp recently, and its heavy enough, why not look at that, as it would still be enough to power you home.
I once used a 2.3hp to power our old Fletcher, when we had an engine problem, it was quite adaquate.
But i think for emergencies you need to have the outboard already mounted so as you can turn it on quickly if need be.

Another problem you may have, is finding an outboard bracket that is suitable for the transom of your boat.

Cheers

Alistair.

 

[tinstaafl]

[ QUOTE ]
I think probably short, but it will depend on where you mount the outboard bracket on the transom.

But DO think about the weight issue, 8hp is a big heavy motor, not easily handled out of a locker, over the rear of the boat and trying to mount onto an outboard bracket on the transon, all that in heavy seas that have caused you main engine to fail!!!! Not Easy.

I have been looking at the Yamaha 4hp recently, and its heavy enough, why not look at that, as it would still be enough to power you home.
I once used a 2.3hp to power our old Fletcher, when we had an engine problem, it was quite adaquate.
But i think for emergencies you need to have the outboard already mounted so as you can turn it on quickly if need be.


[/ QUOTE ]

That's really interesting... After reading some of the posts on previous threads, I had come to the conclusion that 7 or 8 hp was the minimum and it did occur to me that this was quite high for a get-me-home engine for a 19 foot boat! I shall look at the yammy 4 - it will be cheap enough to be able to buy new I would imagine. It's also useful info that you brought essentially the same boat home on a 2.3 /forums/images/graemlins/smile.gif

I think you're right about having it mounted permanently - my only concern being the extra weight at the back. That said, if it was just a 4hp unit it wouldn't be too bad I suppose.

[ QUOTE ]

Another problem you may have, is finding an outboard bracket that is suitable for the transom of your boat.


[/ QUOTE ]

I did find, on the tinterweb somewhere, a bracket that was designed to be attached to swim platforms, etc. I think it was in America but if I had a problem I should be able to construct something.

Thanks Alistair...

tinstaafl

 

[tinstaafl]

Oh, and there's a chap at the beginning of our pier with a 8hp yammy mounted to his swim platform Alistair... I might ask him where he got the bracket.

tinstaafl