O.S. Engines 91SX-H Competition Special - Manual (Page 4)

6
Notes on installing cooling fan and clutch
Do not use a tool which
locks piston when
installing a cooling-fan
and clutch, or top of
the piston may be
damaged. Also, do not
insert a screw driver or
the similar into the
exhaust port.
It is recommended to use Crankshaft
Clamp 7091 (Code No.71530500) available
as an optional tool.
It is made of durable engineering plastic
and locks the crankshaft without risk of
damage to any part of the engine.
Application is as follows:
Remove the crankcase rear cover plate from the
engine and rotate the crankshaft to the bottom
dead center (BDC) position.
Insert the crankshaft clamp so that its grooved
portion surrounds the crankpin and lower end of
the connecting rod and securely tighten the fan
or clutch onto the crankshaft.
Insert this groove onto
the connecting rod.
BDC position
Rotate the crankshaft so that the
connecting rod comes to this position.
7
Note on installing the engine Note on heating the glow plug
Cooling fan cover from some
helicopter models interferes the
heatsink head.
In this case, cut out the cover as
illustrated.
Example
Cut out according to the heatsink head.
Heatsink head, crankcase and cover
plate of the engine are treated with
Alumite which does not conduct
current. Therefore, when heating a
glow plug, connect one lead to the
glow plug and the other to the head
of cover plate fitting screw.
Example