Installation Of The Engine; Throttle Linkage, Silencer - O.S. engine MAX-50SX Ring Owner's Instruction Manual

2. Rotate the needle-valve unit through 90˚ and re-
attach it to the bracket in the required position (see
sketch below).
Note:
As self-tapping screws are used for unit
attachment, screw them in carefully so that screw
threads match those of the unit body precisely.
3.
Finally, secure the complete assembly to rear cover
plate as before.
91FX
Needle Valve unit
Cover plate fitting holes
Needle Stay
Horizontal position
Needle Valve unit Retaining screws
Make sure that the mounting beams are parallel and
that their top surfaces are in the same plane.
CORRECT
Top surfaces
are not in the
Front view Side view
same plane.
Top surfaces are in
the same plane.
Re-align the surfaces
as necessary
How to fasten the mounting screws.
Tighten second
3-4mm steel nuts
nut firmly down
onto first nut.
Tighten this
Spring
nut first.
washer or
lock washer
Hardwood such
3-4mm
as cherry or maple.
steel screw
Steel washer
Hardwood mounting beams
Use mounting screws of a diameter
(between 3mm and 4mm) appropriate
to engine size (see table left).

INSTALLATION OF THE ENGINE

Installation in the model
A typical method of beam
mounting is shown below, left.
Rigid hardwood
(e.g. maple)
50SX
40, 46FX
61, 91FX
Vertical position
(Factory position)
10
THROTTLE LINKAGE
INCORRECT
Opposite
beam Top surfaces
are not in the
same plane.
Engine does not
rest firmly.
3.5mm steel
Allen screw
Note: When adjusting the throttle lever angle,
Spring
relative to the rotor,hold the rotor at about half-way
washer
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.
O.S. radial motor
mount
SILENCER
(cast aluminum)
The exhaust outlet of the silencer can be rotated to
any desired position in the following manner:
11
O.S. radial motor mount
(Available as an optional extra
part. See parts list)
At least
At least
15mm(5/8")
15mm(5/8")
For 50SX, 40/46FX(Code No. 71913100)
For 60FP, 61, 91FX(Code No. 71905200)
Mounting Screw Size
50SX, 40, 46FX 3mm
61, 91FX 4mm
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.)