Fig.5 – O.S. Engines FS-91 II FI User Manual
Page 11
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11
F S
SERIES
F S
SERIES
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 seat firmly.
Make sure that the mounting beams are parallel and that their top surfaces are in the same
plane.
Fig.4
A soft engine mount is recommended but should be made of firm enough meterial to prevent
excessive engine movement but still minimize engine vibration. If engine vibration is excessive the
opening angle of the air valve may vary causing unstable engine operation and possible stalling.
In addition, adequate clearance must be provided to ensure there is no contact between the
injector, temperature sensor and rotation sensor with the airframe.
How to fasten the mounting screws.
Hardwood mounting beams
O.S. radial motor mount
(cast aluminum)
Tighten second nut firmly
down onto first nut.
Tighten this nut first.
Steel washer
5mm steel screw
Spring washer or
lock washer
Hardwood such as
cherry or maple.
Spring washer
5mm steel Allen screw
5mm steel nuts
Fig.5