Furuno FSV-24, Installation Manual

Page: 13 / 110

1-5
1.1.4 Installing hull unit on retraction tank
After welding the retraction tank and allowing sufficient time for cooling, install
the hull unit as follows:
1. Clean the hull unit flange, the O-ring and O-ring groove. Coat them with a
slight amount of grease. Place the O-ring in position on the tank flange.
2. Lay the insulation gasket (1) on the top of the tank flange.
3. Orient the hull unit so that the bow mark (inscribed) on its flange points
toward the ship’s bow. Note that heading adjustment in the display unit is
required if the bow mark does not face the ship’s bow.
4. Confirm that the O-ring and the insulation gasket (1) are in position. Place
the hull unit on the tank.
5. Eleven of the 24 bolt holes on the hull unit flange have already been fitted
with bolts (stern side). Insert the insulator gasket (2) into the bolt holes of the
tank flange to which these 11 bolts are fitted.
6. Coat every bolt, washer and nut with a slight amount of grease to ease
removal. Fit the insulation gasket (2) into the bolt holes of both the tank and
hull unit flanges. Fasten the hull unit to the retraction tank with insulation
gasket (2), flat washers, spring washers and hex bolts.
7. Reinforce the hull unit against vibration by extending stays to the ship’s hull
from the two eye bolts at the top of the hull unit, referring to the figure at the
top of page 1-7.