O.S. Engines 50SX-H - Manual (Page 7)

Because of initial tightness, a
standard electric starter may have
difficulty in rotating the engine when
cold, before it has been adequately
run-in. In this case, use a high-torque
type starter.
DO NOT, however, confuse tightness
with the symptoms of hydraulic lock
caused by an excess of fuel within the
cylinder - often the result of over-
priming.
Attempting to force the engine to turn
over in this condition may cause
internal damage. Instead, remove the
glowplug, invert the engine and eject
surplus fuel from the combustion-
chamber.
Note:
This is a high performance engine
developed expressly for F3C M class
helicopter competition utilizing 50 cubic
inch engines.
The engine uses the same mounting hole
spacing as the O.S. 46FX-H RING making
the two engines interchangeable.
A special machined drive washer and
dual throttle levers are supplied as
standard for helicopter use.
INTRODUCTION
6