your props carefully. The
edges especially are susceptible to bending and dinging if they come into
contact with other hard objects.
some valve grinding compound (available at any hardware or auto parts
store) around your shaft taper. Install
the prop on the taper without the key and rotate 3 or 4 turns in each
direction while pushing prop forward on shaft.
This will remove minor metal imperfections and help assure a proper
fit on the taper. Mark the shaft at the forward end of the prop hub
at it's furthest point of advance with a pencil or magic marker.
prop and wipe off all compound from shaft taper, prop bore, and keyway.
key in shaft keyway. It
should fit snugly and “bottom out” in keyway.
Remove from shaft and try for same fit in prop keyway.
If any areas bind or won’t fit properly, dress the key lightly
with sandpaper wrapped over a flat surface.
If the key rocks or is loose, replace it, as looseness here can
cause vibration and possible shaft damage.
key in shaft keyway and after aligning prop keyway, slide prop up onto
shaft to the point which you previously marked.
At this point the key should be completely captured by the prop and
centered laterally within the prop hub.
Never, ever, hammer on the propeller to make it fit on the shaft.
If the prop doesn't move up to your marked point, the key is binding due
to poor fit.
your large shaft nut and hand tighten up against hub. At this point many
installers will place a block of wood between the boat bottom and end of
propeller to keep the shaft from turning while they tighten the nut with a
wrench. This practice should be avoided if at all possible,
as it can cause blade distortion.
Use a plumbers strap wrench to hold the shaft or have a friend hold
the prop down close to the hub while you tighten the nut and firmly seat
the prop on the taper.
you have a single "castle" type nut, finish by installing your
cotter pin at this point. If you have two nuts, remove the large
shaft nut and replace with the small one. Tighten small nut using the same procedures as in step 6.
Now, thread on your large shaft nut behind the small one and
tighten (this is your lock nut).
cotter pin, and bend back prongs.
do not recommend painting propellers as it degrades performance, can cause
electrolysis, and generally does little to retard marine growth.
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