<< It may not be a degradation of the hole in which the pin fits as I
suggested
earlier but perhaps a failure in a damper material somewhere else in the
drivetrain, excessive play in the forward - neutral clutch, any number of
things might be wrong. My point is that it's unlikely that it was designed to
fail as it doing, that there is a repair that will fix it and one shouldn't
just accept it and use workarounds or be dependant on a pocket full of spare
shear pins. Although I have never approached the manufacturer of these engine
>>
My first thought about this problem was that maybe idle speed could be set too
high and shifting gears is shearing the pin. After the suggestion of problems
with the shaft pin hole I thought about the weakest part here...
If you go by the weakest part to wear out... The prop hole for shear pin may
have worn out larger, allowing prop to lash back and forth and shear the pin.
A check of shear pin fit against propeller may be worthwhile to check for
tigthness. If it is too loose, placing something in prop to prevent lashing
back and forth would be in order. Or maybe it's time for a new prop? Or maybe
the prop is not on tight enough allowing it to wiggle?
Any other solutions?
SF