O.S. Engine MAX-10LA Instruction Manual - page 13
24
BEWARE of
the rotating
propeller.
13
Engine starts
If the engine does not start, refer to the
TROUBLE SHOOTING CHART on page 32-
33.
In the interests of safety, keep your face and
other parts of the body away from the vicinity of
the propeller.
Listen to the sound
carefully.
14
Needle-valve adjustment (1)
Slowly advance throttle to its fully open
position, then gradually close the needle-valve
until the exhaust sound changes pitch.
Close the needle-valve gradually until a high-
pitched exhaust note begins to be
superimposed on the lower-pitched sound.
25
15
Disconnect battery leads
Disconnect the battery leads from
the engine with care so that the plug
clip does not touch the rotating
propeller.
If the engine stops when battery
leads are disconnected, close the
needle-valve a little
(approx.45˚)
further, and restart
the engine.
16
Needle-valve adjustment(2)
As the needle-valve is closed beyond the initial
readjustment, the rpm of the engine will be
increased and a continuous high-pitched
exhaust note, only, will be heard.
Key to the needle-valve
adjustment.
(Turn 20-30˚ at a time.)
Turn the needle-valve 20-30˚ in the direction of
arrow, and wait momentarily for the change of
r.p.m. After the rpm of the engine is increased, turn
the needle-valve another 20-30˚ and wait for the
next change of r.p.m.
As the speed of the engine does not instantly
change with needle-valve readjustment, small
movements, with pauses between, are necessary
to arrive at the optimum setting.
IMPORTANT NOTE
When fine-tuning the needle-valve to reach
peak per-formance, take care not to run the
engine too lean and cause it to overheat.
Be sure to observe the simple running-in
procedures described on Page 27.