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Items necessary for starting
Tools, accessories, etc.The following items are necessary
for operating the engine.
BEFORE STARTING
Fuel
INSTALLATION OF THE ENGINE
Make sure that only the under-surfaces
of the engine’s mounting lugs are in
contact with the engine mount.
INSTALLING THE GLOWPLUG
Install washer on glowplug and insert carefully into
Heatsink-head, making sure that it is not cross-threaded
before tightening firmly.
INSTALLATION OF THE CARBURETOR
CARBURETOR CONTROLS
The under-surfaces of all O.S. engine beam mounting
lugs are precision machined flat and exactyly parallel
to the engine's horizontal axis. It is essential that the
engine mounts in the model are also accurately made
and aligned. If they are not, they will cause stress and
distortion within the engine itself, probably resulting in
loss of performance and internal damage.
The recommended screws for securing the engine to
the engine mounts in the model are 3mm or 4-40 steel
Allen type. It is also advisable to use lock washers or
LOCTITE to prevent nuts from loosening.
Select, by practical tests, the most suitable fuel from
among the best quality fuels available in your country
for helicopter use. For the best throttle response, a fuel
containing 10% to 30% nitromethane is preferable.
Lubricants may be either castor-oil or a suitable
synthetic oil (or. a blend of both) provided that they are
always of top quality. For consistent performance and
long engine life, it is essential to use fuel containing AT
LEAST 18% lubricant by volume. Some fuels
containing coloring additives tend to deterriorate and
may adversely affect running qualities. If in doubt
compare to a fuel known to be good.
Retainer screw
Carburetor Rubber Gasket
0.2mm gap
As delivered, the engine has its carburetor lightly
fitted into its intake boss. Secure it as follows.
With a fixed-wing model, power failure is rarely a
serious threat to the safety of the aircraft since it can
usually glide down to a safe landing. In a helicopter,
on the other hand, it is vitally imporant that the engine
keeps running and that there is a quick and reliable
response to the throttle in order to ensure safe ascent
and descent of the model.
A
B
The Medium Speed Needle Valve
This is an extra control that can be brought into play,
if necessary, after adjusting A and B above. It
provides the means of fine-tuning mixture strength
over that all-important part of a helicopter's throttle
range where the model is flying in, or near, the
hovering mode.
C
BASIC POSITION OF MIXTURE CONTROL SCREW
(Mixture Control Valve)
Rich
Mixture Control Valve
MIxture Control Screw
Lean
As delivered, the Mixture Control Screw is positioned at
approximately the center as shown in the sketch.
Mixture gets lean when the Mixture Control Screw is
turned right, while mixture gets rich when the Mixture
Control Screw is turned left.With a model helicopter,
adjustments vary with combined various factors such as
climatic conditions, fuel, muffler, main rotor, weight of
the model, gear ratio, etc. Therefore the Mixture Control
Screw position varies with each model and set- up, and
it is normal if the Mixture Control Screw position is off
the center.
89 degrees
When the triangle mark on the carburetor rotor meets
the far right mark, the throttle is fully closed.
When the triangle mark meets the top mark, the throttle
is fully open. The range is 89 degrees. You may use the
other three marks as the reference marking of throttle
opening to your preference when hovering.
WARNING!
Never try to check the triangle mark position while
the engine is running and rotor is rotating, or you
may be hit by rotating rotor which results in serious
injury. Stop the engine and rotor before checking
the triangle mark position.
Carburetor Rotor
Carburetor Body
Fully closed
position
Fully opened position
As shown in the sketch, the carburetor has graduation
marks.
GRADUATIONS ON THE CARBURETOR BODY
Battery leads
1.5 volt dry cell
These are used to conduct current from
the battery to the glowplug. Basically, two
leads, with clips, are required, but, for
greater conve-nience, twin leads with
special glowplug connectors, as shown on
the right, are commercially available.
Battery leads
glowplug Igniter
The power source for heating the glowplug may be
either a large heavy-duty 1.5volt dry cell, Ni-cd battery
or glowplug Igniter.
Glowplug battery
Make sure glowplug element glows
bright red inside room or shadow.
Battery leads
In case of 1.5volt dry cell
12V Battery
Starter
Electric starter and starter battery
An electric starter is recommended
for starting.
Hexagon starting shaft
This shaft mounted on an electric starting motor
is driven into the shaft cup to turn the engine.
Alternatively, one of the purpose-made
manual or electric fuel pumps may be
used to transfer fuel directly from your fuel
container to the fuel tank.
Manual
Electric
It is recommended to install a good
in-line filter between the fuel tank and
carburetor to prevent entry of foreign
matter into the carburetor.
Fuel Filter
Fuel Pump
TOOLS
Screwdriver
Necessary for engine installation.
1.5mm, 2mm, 2.5mm, 3mm
Necessary for carburetor adjustments.
No.1, No.2, etc
Phillips Screwdriver
No.1, No.2, etc.
Socket Drivers
5mm, 5.5mm, 7mm
Hex Drivers
Install a filter to the outlet tube of your
refueling container to prevent entry of
foreign matter into fuel tank. O.S. ‘Super
Filters’ (large and small) are available as
optional extras.
O.S. Super Filter (Fuel Can Filter)
O.S. SPEED PLUG WRENCH
(optional extra)
Loosen the retainer screw, rotate the carburetor to its
correct position and press it well down into the intake
boss, compressing the rubber gasket as shown in the
sketch, before re-tightening screw.
Rotate the retainer screw gently until it stops, then
tighten a further 90-120 degrees. Do not over-tighten
the screw as this will damage the carburetor body.
1.
2.
The High-Speed (Main) Needle Valve
When set to produce maximum power at full
throttle, this establishes the basic fuel/air mixture
strength. This is then maintained by the carburetor's
automatic mixture control system to cover the
engine's requirements at reduced throttle settings.
The Idle Mixture Control Screw
This provides the means of manually adjusting the
mixture control valve. By setting the Mixture Control
Screw for the best idling performance, the mixture
control valve automatically ensures that fuel is
accurately metered to maintain the correct mixture
strength as the throttle is opened.
Three adjustable mixture controls are incorporated in the
Type 40L. They are as follows.
Idle MIxture Control Screw
High Speed Needle Valve
(Main Needle)
Medium Speed
Needle Valve
As the idle mixture control screw is installed
with LOCTITE, it may initialy feel stiff, and it is
suggested to use a slightly oversized
screwdriver. The screw can be turned only 90
degrees either way. Do not force to turn
further, or it may break or cause trouble.
NOTE
90 degrees
90 degrees
Be sure to use an electric starter to start the engine.
Fill the fuel tank with fuel. When filled, prevent the
fuel from flowing into the carburetor with a
commercially available fuel stopper, etc.
Release the stopper before starting the engine.
1.
2.
Starting procedure is as follows:
Make sure that plug element glows red, and install
the plug in the cylinder head.
STARTING
Open
1.
2.
Opening and closing of the Needle-Valve
Turn the needle clockwise to close the needle-valve,
and turn the needle counter-clockwise to open the
needle-valve as shown in the sketch.
High Speed needle-valve:
Idle Mixture Control Screw:
at basic position when the engine leaves the factory.
Medium Speed needle-valve:
Close
4. Checking the rotating direction of the starter
3. Preparation of the starter
Be sure to use a muffler pressurized fuel feed.
Use the same fuel as you intend to employ for
actual operation of your model.
exactly two turns open from the fully closed
position. (Note: If a different muffler is used, this
setting may require readjustment)
exactly two turns open from the fully closed position.
Make sure that the starter rotates
to the direction shown in the
sketch. If the direction is reverse,
reverse the leads on battery.
Install the starting shaft to the
starter securely.
Improper installation will allow the
shaft to swing creating a dangerous
situation.
The connection between the fuel tank and the engine.
ID. 2.5mm Length 1000mm
O.S. SPEED SILICONE FUEL LINE (optional extra)