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Steven Shelikoff
 
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Default Angle of prop shaft - theoretical question.

On Tue, 08 Jun 2004 12:08:33 -0400, Wayne.B
wrote:

On Tue, 08 Jun 2004 01:28:20 GMT, (Steven
Shelikoff) wrote:
My prop is about 3 ft down. The
clearance to the hull above it is around 3 to 4 inches. There's still
about 5 or 6 feet of waterline behind the prop. So on the upward
stroke, the blade is pushing the water column against the hull.


======================================

Charles Low conjectured, and I think he may be right, that it is this
force of the prop wash hitting the hull that causes the "walk". It's
the only explanation that seems to hold up to scrutiny with different
hull and prop configurations.


It could be a contributing factor but not the only one, and maybe not
even the most important for some boats. You can have propwalk even with
no prop wash hitting the hull, like when you first start out in forward
from a standstill with a boat that has the prop beyond the stern of the
boat (an outboard or sterndrive.) It's just not as noticable because
you can control it better in forward.

Steve