10
Mounting Screw Size
50SX, 40, 46FX
61, 91FX
3mm
4mm
INSTALLATION OF THE ENGINE
Rigid hardwood
(e.g. maple)
At least
15mm(5/8")
At least
15mm(5/8")
O.S. radial motor mount
(Available as an optional extra
part. See parts list)
A typical method of beam
mounting is shown below, left.
Installation in the model
50SX
40, 46FX
61, 91FX
For 50SX, 40/46FX(Code No. 71913100)
For 60FP, 61, 91FX(Code No. 71905200)
Finally, secure the complete assembly to rear cover
plate as before.
3.
Vertical position
(Factory position)
Horizontal position
Cover plate fitting holes
Needle Valve unit
Needle Valve unit Retaining screws
Needle Stay
As self-tapping screws are used for unit
attachment, screw them in carefully so that screw
threads match those of the unit body precisely.
Note:
Rotate the needle-valve unit through 90˚ and re-
attach it to the bracket in the required position (see
sketch below).
2.
91FX
11
Before connecting the throttle-lever/servo linkage,
make sure that no part of the linkage interferes with
the internal structure of the aircraft or wiring, etc.,
when the throttle is fully open or fully closed.
Set the throttle lever linkage so that the throttle rotor is
(a) fully open when the transmitter throttle stick is fully
advanced and (b) fully closed when the throttle stick
is fully retarded. Adjustment of the throttle rotor open-
ing at the idling position can then be made with the
throttle trim lever on the transmitter. (Select throttle-
lever and servo-horn hole positions that will avoid ex-
cessive pushrod travel causing the throttle to bind at
either end.)
THROTTLE LINKAGE
Note: When adjusting the throttle lever angle,
relative to the rotor,hold the rotor at about half-way
between the open and closed positions while
loosening and tightening the fixing screw, otherwise
the rotor, rotor guide screw,throttle stop screw or
carburettor body may become burred and damaged.
The exhaust outlet of the silencer can be rotated to
any desired position in the following manner:
SILENCER
Hardwood mounting beams
O.S. radial motor
mount
(cast aluminum)
How to fasten the mounting screws.
Make sure that the mounting beams are parallel and
that their top surfaces are in the same plane.
Front view
Side view
Top surfaces
are not in the
same plane.
Opposite
beam Top surfaces
are not in the
same plane.
Re-align the surfaces
as necessary
Engine does not
rest firmly.
CORRECT
INCORRECT
Top surfaces are in
the same plane.
Tighten second
nut firmly down
onto first nut.
Tighten this
nut first.
Steel washer
3-4mm
steel screw
Spring
washer or
lock washer
Hardwood such
as cherry or maple.
Spring
washer
3.5mm steel
Allen screw
3-4mm steel nuts
Use mounting screws of a diameter
(between 3mm and 4mm) appropriate
to engine size (see table left).
