O.S. Engines 50SX - Manual (Page 19)

6. Connect battery leads to glowplug.
Bring electric starter into contact with spinner-nut
or spinner and depress starter switch for one or
two seconds. Repeat if necessary.
When the engine starts, withdraw the starter im-
mediately. 7.
Attention :
Do not choke the carburettor air intake when applying
the starter. This could cause an excessive amount of
fuel to be drawn into the cylinder which may initiate
an hydraulic lock and damage the engine.
If the engine does not start within 10 repeat
applications of the starter, remove the glow-plug,
check that it glows brightly and that the cylinder is not
flooded with fuel. (To eject excess fuel, close needle-
valve and apply starter with glowplug removed.) Then
try again.
VERY IMPORTANT!
Before being operated at full power (i.e. at full-throttle and
with the needle-valve closed to its optimum setting) the
engine must be adequately run-in, otherwise there is a
danger of it becoming overheated and damaged.
Fill the fuel tank. Do not allow fuel to overflow into
the silencer, otherwise the engine may become
flooded and difficult to start.
Check that the needle-valve is closed. (Do not
overtighten.) Now open the needle-valve counter-
clockwise to the starting setting:-
1 ~ 2 turns for 50SX,40,46,61FX
2 ~ 2 turns for 91FX
3 ~ 4 turns for 61FX when a tuned silencer is used.
2
1
2
1
3.
4.
•
•
•
5. Open the throttle approx. one-quarter.
(This is to avoid unnecessarily
high r.p.m. when the engine starts.)
Turn needle-valve clockwise to close
(for leaner mixture)
Turn needle-valve counter-clockwise
to open (for richer mixture)
Mark
Close
Open
Fully closed
position
Fully opened position
Set at this point
1
4
3
4
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