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Steve W.[_2_]

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

What you're looking for is basically a work boat design. I ran a 14'
hull with a home brewed straight shaft with a variable pitch prop. It
allows you to adjust the speed and direction without changing the engine
rpms. Engine was a 16 HP Briggs twin from a Cub Cadet tractor. Even used
the factory engine plate because the engine sets at an angle already.
Air cooled and exhaust ran out through a car muffler and out the
transom. Built a tower in the middle that covered the engine, held the
prop direction and steering controls for the rudder. The prop came from
an outfit called Marine Propeller.
Not super fast but it worked well enough. I have since replaced the
entire boat with a 15 foot bass tracker that was a salvage hull.

this one uses a similar prop but a 5 horse engine
http://www.youtube.com/watch?v=bmNEO...eature=related

--
Steve W.