Small gearbox

[presumingjosh]

Hello,
For a summer project i have been converting an old lawnmower engine into a marine inboard engine. Ive just finished the water cooling system and its working well but i now need to find a gearbox which is hard seeing as the engine is so small, the only way i can think round it is to make my own gearbox out of bits from an old motorcycle one but this could be very unreliable. If anyone has any ideas or know of any gearboxes that would suit my specification please tell me of them. The engine is about 3hp and it will need to be a straight shaft from engine - gearbox and then gearbox - prop.
Cheers,
Josh

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[boatless]

At 3hp wouldn't belt drives be a viable alternative to gearboxes AND clutches?

<hr width=100% size=1>my opinion is complete rubbish, probably.

 

[presumingjosh]

sounds like a good idea to me, i will look into it,

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[TrueBlue]

May not be very sensible, but how about a transaxle from a garden tractor?

Belts only seem simple but:-
Don't you need to go backwards on occasion (if only to slow you down)
You will need a bearing to take the sideways thrust from the belt arrangement.

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Stop what you're doing and wait my signal

 

[presumingjosh]

I did think about having to reverse and a belt drive would be no good for that. Know of anywhere where i could pick up a transaxle or similar device?

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