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Using a 3/16" drill bit or a
propeller reamer, enlarge the
hole in the propeller hub to fit
the crankshaft. The diameter of
the crankshaft is 5mm. Slide the
propeller onto the crankshaft, up
against the drive washer. Slide
the propeller washer up against
the propeller and thread the
propeller nut into place. Tighten
the propeller nut firmly to secure the propeller into place. When tightening the
nut, use an adjustable wrench. Do not use pliers.
WARNING
If you are installing a spinner onto your engine, the cone
of the spinner must not rub against the propeller. Allowing the spinner
cone to rub against the propeller could lead to propeller damage and
eventual propeller failure.
NOTE: PROPELLER SHAFT THREAD SIZE IS 5MM.
Engine Bolts and Firewall Requirements
The engine should be mounted to either a glass-filled nylon engine mount, a
machined aluminum engine mount or an integrated hardwood beam mount.
Use only high-quality 1/8" (3mm) steel cap screws and related hardware to
mount the engine to the engine mount. The firewall in the airplane should
be aircraft grade plywood no less than 3/16" thick and the firewall should
be reinforced to meet the torque and weight of the engine.
Fuel Tank Size and Orientation to Carburetor
Ideally, the stopper in the fuel tank should be level with the high speed needle
valve or just slightly below it. Some models will only allow the fuel tank to be
mounted higher than the ideal location. A fuel tank that is positioned higher
than the ideal location usually doesn’t pose any problem except when it is
mounted excessively higher and/or is used in conjunction with an inverted
mounted engine or during extreme aerobatic flight. If you mount the engine
inverted, we strongly suggest lowering the fuel tank so the stopper assembly
is slightly below the high speed needle valve. Doing this will prevent fuel
from siphoning into the engine and flooding it when the fuel tank is full. If
you cannot lower the fuel tank far enough, we suggest lowering it as far as
can be allowed in your particular application.
The size of the fuel tank used should be 4oz. - 6oz., depending on the
model and the length of flights desired. Use of a 6oz. tank will provide
approximately 15 minutes of run time at full throttle. Use of a fuel tank any
larger than 6oz. can lead to excessive leaning of the engine during flight
and is not recommended.
Carburetor Installation
The carburetor is held in place using the pinch bolt and retaining nut already
installed in the crankcase. Slide
the base of the carburetor into the
crankcase, being careful to keep
the carburetor perpendicular to
the front of the engine. Using
your thumb, push down firmly on
the carburetor so that the base
of the carburetor sets completely
into the crankcase. An o-ring
is installed on the carburetor
throat to seal the joint. While holding the carburetor down firmly, gently tighten
the retaining nut to draw the pinch bolt into place.
WARNING
Do not overtighten the retaining nut or damage to the base
of the carburetor could occur.
Muffler Installation
The muffler is mounted to the engine using the two socket-cap screws, two
split washers and one of the two
gaskets provided. The second
gasket should be kept as a spare.
Tighten both screws firmly to
prevent the muffler from loosening
during flight. The exhaust cone
on the back of the muffler can be
adjusted to better match the in-
stallation of your particular ap-
plication. To adjust the exhaust
cone, loosen the retaining nut, rotate the cone to the desired angle, then
tighten the retaining nut firmly while holding the axial bolt in place from the
front of the muffler.
It is important to tighten the retaining nut firmly to
prevent the exhaust cone from loosening during flight.
Carburetor Rotor Bolt
The rotor bolt holds the throttle barrel in the carburetor body and requires
no adjustment. As part of your
maintenance schedule you
should periodically check that
the rotor bolt is tight and that the
gasket is not damaged.
Adjusting the Idle Speed
The carburetor does not feature
an idle stop screw like some
engines, instead opting to adjust the idle speed via the transmitter. You
will need to set up your transmitter throttle trim lever to keep the engine at
a low idle when the trim lever is centered, then to shut off the engine when
the trim lever is pulled all the way back.
Needle Valve Extension
If an extension is required to
adjust the high speed needle
valve, use a 1.5mm diameter wire of the necessary length (not included).
Loosen the grub screw in the side of the needle valve using a 1.5mm hex
wrench, insert the wire into the end of the needle valve, then tighten the grub
screw firmly. If the extension is more than a few inches long we recommend
supporting the outer end of the extension to prevent excessive vibration.
Adjusting the Throttle Arm Position
The throttle arm angle can be adjusted to better suit your particular
application. Loosen the throttle
arm retaining nut, adjust the
angle of the throttle arm either
forward or backward, then firmly
tighten the retaining nut.
Propeller Installation
WARNING
Before installing the propeller it must be balanced. Running
your engine using an out-of-balance propeller can lead to excessive
vibration, which will result in excessive stress and wear on both the engine
and the airframe. Balance the propeller using the method recommended
by the propeller manufacturer. Several products are available to properly
balance propellers. Ask your local retailer for more information about
these items.