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INSTALLATION
GB
BOW THRUSTER BTHY185-250-300 IT GB - REV003A
• To avoid cavitation in the propeller,
the tunnel must be positioned as low
as possible.
• The lever effect in the boat is propor-
tional to the increase of the distance
(L1 and L2) between the barycentre and
the position of the tunnel A and B.
For greater lever effect prefer
position B to position A.
minimum 0.75
times tunnel Ø
BARYCENTRE
L 1
L 2
A
B
INSTALLATION REQUISITES:
THE TUNNEL
• An increase in the length of the tun-
nel increases the effect of the loss of
charge, decreasing the nominal driving
force.
• To limit losing thrust, the optimal
length is equal to 3-4 times the tube
diameter; a ratio of up to 6 can be tol-
erated.
• The position of the tunnel will depend
on the interior and exterior shape of
the boats bow.
• Optimal positioning of the tunnel
will be in the bow and as low as pos-
sible, at least 0.75 times the tunnel
diameter from the waterline.
F