6
Because the FS-70 ULTIMATE is a powerful, large-
displacement, single-cylinder four-stroke-cycle engine, it is
essential to use very substantial engine mounting.
Conventional wooden mounting beams should be of rigid
hardwood and of at least 15mm or 5/8-in square section.
INSTALLATION
Make sure that these mounting beams are accurately aligned
and firmly integrated with the airframe, reinforcing the
adjacent structure to absorb vibration. Use 3mm or larger
steel screws, preferably Allen type hexagon socket head cap
screws, with washers and locknuts, for bolting the engine to
the bearers.
Make sure that the mounting beams are parallel and that their
top surfaces are in the same plane.
Front view
CORRECT
Side view
Top surfaces are
in the same plane.
Re-align the surfaces as necessary
INCORRECT
Top surfaces are not
in the same plane.
Opposite beam
Top surfaces are not in the same plane.
Engine does not rest firmly.
How to fasten the mounting screws.
Hardwood mounting beams
Radial motor mount
(cast aluminum)
Tighten second nut firmly
down onto first nut.
Tighten this nut first.
Steel washer
3mm steel nuts
3mm steel screw
Spring washer or
lock washer
15mm min.
15mm min.
Hardwood such as
cherry or maple.
Spring washer
3mm steel Allen screw
7
FUEL TANK & LINES
10-15mm
A fuel tank of approximately 300cc capacity is suggested.
This allows up to 12-13 minutes flying time, dependent
upon the type of fuel used, the size of the propeller and on
the proportion of full-throttle to part-throttle operation
through the flight.
Fuel
supply line
Tank pressure
vent line
T nipples (sold separately)
Fuel filter (sold separately)
Caps (sold separately)
A
C
JAPAN
B
To prevent the pickup from adhering to the tank wall under
suction and restricting fuel flow, slots may be filed in the
end of the weight as shown. Alternatively, a Non-Bubble
type weight (Code No. 71531000) may be used.
Make sure that the tank is well rinsed out with methanol or
glow fuel before installation and that the pickup weight is
well clear of the bottom of the tank when held vertically (see
sketch).
Fuel filter - Do not use a felt type filter.
Since high pressure is applied to the fuel tank from the
engine crankcase, use a thick-walled strong enough tank
and securely seal the area around the cap.