View Full Version : Outboard leg or 90 degree drive

The Error Guy
27-11-2010, 12:35 PM
Recently started restoring an old boat that we used to use up and down the drains and inlets. It has no engine anymore and after finding that 3.5hp outboards that are even older than me seem to retail for around $250 on TM I decided screw this! i'm going to improvise!

Taking my usual "i'm not gonna pay for that" I set about finding what else I could use for power, 10 mins later, I spy with my little eye... a lawnmower. Seemed perfect, actually so perfect in fact hordes of Aussies and Americans seem to be scooting around with their faithful mowers strapped to their boats, there's a positive youtube infestation of them!

Win for me, except now its a problem as although the engine part is easy, I still need an outboard leg to put the engine on, either that or I can get a 90 degree drive and make my own "leg" of sorts. A quick search on TM shows the usual aging grandpa outboard sitting around for $250 so but no legs without engines for parts.
I was wondering if anyone knows where I can get a 2nd hand (or new but that would probably cost more $$) outboard leg or 90 drive for this project.

Preferably around wellington/masterton


TNEG (The nautical error guy)

27-11-2010, 12:53 PM
I thought I was bad for doing this sort of thing. I suspect however there'll be less pain if you buy youself an outboard, with motor.

An alternative however, if the lawnmower motor will start, run and distribute oil properly while on a 90 degree tilt is to use it with an inboard arrangement - then you no longer need the elbow/gears, and can get away with a drive shaft and thrust bearing.

However, as I understand it, a mowers blade is also meant to contribute towards the function of a flywheel, which is a benefit you won't get with a propellor in water.

The Error Guy
27-11-2010, 01:13 PM
Less pain? heck $200 is a lot of pain for some puny outboard. anyway, I doubt it will run nicely on its side. as for the fly, I will have to get something similar to a centrifugal ball governor (similar to this http://cache2.allpostersimages.com/p/LRG/17/1751/KVT3D00Z/posters/thurston-robert-h-governor-or-fly-ball-governor-invented-by-james-watt-to-regulate-the-supply-of-steam.jpg) and put it on the drive shaft. after taking the blade of the mower started but barely ran. Exhaust was very rich to it was definitely not burning properly.

27-11-2010, 08:52 PM
I've once heard of it being done but it was connected to a prop shaft not a stern leg

27-11-2010, 09:17 PM
In talking to my father in law he has told me there used to be kits available to do this exact thing. He says he hasn't seen one in years however.

27-11-2010, 11:56 PM
My mate's got an old outboard for parts. He's looking for $210 for the leg. PM me if you're keen.

28-11-2010, 07:54 AM
Why don't you go for something like a traditional Thai longboat .... 1600 Toyota motor with a straight shaft weed-eater with a prop on the end ... have a close look at the prop on the back of the boat ... cuts through the weeds too :D


The Error Guy
28-11-2010, 12:50 PM
cheers for Ideas and all, I'll probably get 2x 45 deg gears from somewhere to make a 90 deg turn for the drive. just need to find some welding gear now xD.