14
4
1
STARTING
Install an appropriate propeller and tighten securely.
To facilitate electric starting, fit an spinner for centring
the rubber drive insert of the starter.
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 1 turns from
the fully closed position and temporarily set the throttle
in the fully open position.
2
1
Turn needle-valve clockwise to close
(for leaner mixture)
Turn needle-valve counter-clockwise
to open (for richer mixture)
Mark
Close
Open
1.
2.
3.
4.
(When the 10-20% nitro fuel is used)
5. Open the throttle approx. one-quarter.
(This is to avoid unnecessarily
high r.p.m. when the engine
starts.)
Fully closed position
Fully opened position
Set at this point
4
3
Connect battery leads to glowplug.
Bring electric starter into contact with spinner and
depress starter switch for one or two seconds. Repeat if
necessary. When the engine starts, withdraw the starter
immediately.
7.
Attention :
Do not choke the carburetor 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.
8. When the engine starts, advance the throttle stick slowly
checking the increase of r.p.m. Abrupt throttle operation
right after starting may cause the engine to stumble or
stop.
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.
6.
15
RUNNING-IN ("Breaking-in)
For long life and high-performance, this engine needs to
be properly "run in", or "broken-in". The following settings
apply when using a fuel containing not less than 15%
lubricant and not more than 10% nitromethane.
Needle-valve setting for starting
2
1
Open the needle-valve 1 turns from the fully closed
position. When using the optional fine-tapered needle
supplied with the engine, open the needle-valve
approx. 2 turns.
Bench or ground running
Preferably, use a propeller of slightly lower pitch than
the one intended for actual flight. Start the engine and
open the throttle. Close the needle-valve gradually and
allow the engine to run at its maximum r.p.m. for just
one or two seconds, then immediately reopen the
needle-valve a half-turn and run the engine with this
rich mixture for 5 to 6 seconds.
Repeat this procedure until the fuel tank is empty.
Idling adjustment
Start the engine with the needle-valve setting at the
original starting position. Close the needle-valve
gradually and set it at 1/8 to 1/4 turn opened from the
maximum r.p.m. position. Adjust the idling with this
needle-valve setting.
In-flight running-in
During the first 3 or 4 flights, try to avoid successive
nose-up manoeuvres. Since, during running-in, the
engine will tend to overheat, set the needle-valve
carefully so that the mixture is always slightly rich. If the
mixture becomes lean during a nose-up manoeuvre
such as a loop, land the model and open the needle-
valve 1/8 to 1/4 turn. If the engine becomes too rich
during level flight with this needle-valve setting, increase
the header pipe setting 10 to 20mm and re-set the
needle-valve. At least 10 flights are required for the
completion of running-in. Note that the engine will
develop its full performance only after running-in is
completed.
Model engines generate considerable heat.
Do not touch any part of your engine until it
has cooled. Contact with the muffler (silencer),
cylinder head or exhaust header pipe, in
particular, may result in a serious burn.
16
2
1
Note:
It is important to be able to run the engine on a rich
mixture during the breaking-in period to avoid
overheating. If the fuel/air mixture does not become
sufficiently rich, even when the needle-valve is opened
more than 5 turns, first check that the carburetor has
not become clogged with dirt or fluff. Also check that
the fuel tubing has not become holed or split and that
the fuel pick-up weight is not sticking to the tank wall.
(See previous reference to 'FUEL TANK'.) If, at any
time, the engine cannot be persuaded to run rich after
checking the above, it is possible that a fault has
developed in the pump. In this case, consult the O.S.
engine distributor in your country.
As the running-in proceeds, a slightly different idling
mixture will be required for best carburetor performance.
Therefore, adjust the mixture control valve accordingly.
During the first few (running-in) flights, the engine may
sometimes stop because the carburetor adjustments have
yet to be finalized at this stage. Be prepared, therefore,
to make an emergency landing at this time.
MIXTURE CONTROL ADJUSTMENT
Before starting the engine, open the Needle-Valve 1
turns from the fully closed position.
(When the 10-20% nitro fuel is used)
Set the throttle very slightly open from the idle position
and start the engine in the usual way. It is preferable to
have the throttle only slightly open, to avoid
unnecessarily high revolutions when the engine starts.
Now open the throttle fully and gradually close the
Needle-Valve until the engine is running at its maximum
speed.
Do not close the Needle-Valve to too lean a setting, as
this will cause overheating which may result in internal
damage and reduced engine life. Set the Needle-Valve
approximately 3 to 4 clicks open (i.e."rich" ) from the
peak r.p.m. setting, even though this will slightly reduce
r.p.m. on the ground.
Make sure that the engine is fully "run-in" before
operating it continuously at full power.
Having set the Needle-Valve as described above, close
the throttle. The engine should idle steadily and
continuously. (If it stops immediately, first try turning the
Throttle Stop Screw clockwise a few degrees to raise
the idling speed a little.)
