On Tue, 25 Oct 2011 18:16:03 +0000 (UTC), wrote:

Greetings All,
I have a 12 foot aluminum boat that is rated for a 10 HP max motor.
I do have a 10 hp outboard but bone on bone joints in both wrists
makes it really painful to put the motor on. For years I have been
thinking about various schemes to put in a liquid cooled 4 stroke
inboard. One idea is to use a conventional air cooled flat head motor
that's been modified with a water jacket. I told Harold Vordos about
this idea and he had done it and it worked well. I mean the liquid
cooling conversion. He even had done it with a motor that was very
close to a 7 hp motor that I have and was considering. I have also
thought about using a 125 to 250 cc motorcycle motor. But these are
expensive and rev higher. I have several reasons for wanting to do
this project. Mostly I want a quiet power plant and a liquid cooled
engine inside some sort of housing seems like it would fit the bill. I
want 4 stroke mainly because I'm tired of putting oil in the water. I
also want reverse and am not sure what is the best way, at least for
me. The plan is to use a prop shaft that pierces the bottom of the
boat and a rudder. So the motor would be inboard as would the
reversing gear. Money is tight so don't suggest a Crosley engine. If I
could even find one for sale. Any thoughts?
Thanks,
Eric

Stupid question: Why not leave the boat alone (through hull = leaks =
that sinking feeling...) and just build a davit hoist at the dock and
modify a 4-wheeled hand truck for handling the engine?

You find yourself a really nice 10 HP 4-stroke outboard...

Then either take some steel stock and build a lifting yoke that wraps
around the housing and puts a hoisting eye right over the CG. Or you
pop open the little plastic plug on top of the engine (or take off the
top shroud) and find the factory lifting hole at the balance point,
and buy a lifting eye with the right threads.

Oh, and put a second eye on the side of the motor where you can clip
on a tag-line rope, with the other end attached to the dock - Just in
case the motor takes an unscheduled swim...

Davit hoist on the dock, that's a no-brainer of engineering. But
considering the proximity to water, I'd use a 12V winch and a battery
box so you just hit the "UP" button when you want to go, and you can
trickle charge the battery. Even a solar panel.

120V winches and GFCI's don't get along well, so forget that.

And you take (or make) a 4-wheel dolly with a bracket that looks
suspiciously like a transom, drop the motor on it and wheel it off to
the garage. Could even have space planned in for a plastic trash can
on it for flushing out the motor.

10" pneumatic tire casters if you'll be dealing with grass and dirt,
and humongous flotation tires and a "Radio Flyer" steer axle if you
have to cross sand.

-- Bruce --