Fuel
• Mix a ratio of gasoline to oil of 20:1
for break-in and continuous operation
on all engines.
• A mixture of commercial regular
gasoline and a reliable High quality
100% Synthetic oil for 2-cycle
engines must be used (we
recommend Evolution Oil,
EVOX1001Q). Unleaded high-octane
gasoline is not required for
Saito engines.
• Remember to use caution in the
storage, use and transport of gasoline.
• Since commercial gasoline has
many impurities, please be sure to use
a reliable fuel filter (SAI50109) in
your fuel system.
Note:
• Be sure to use a gasoline-resistant
type of fuel tubing (like Tygon). DO
NOT use any silicone rubber type of
fuel line to the engine or in the
fuel tank.
• The use of fuel with up to 10%
ethanol has been tested and found to
work fine.
Fuel Tank and
Plumbing
Be sure to include a reliable fuel filter
in your fuel system. The drawing above
suggests use of a fuel feed line and an
air intake line. Also, be sure to use a fuel
line compatible with gasoline.
IMPORTANT:
Air is necessary to cool
the engine during operation. Make sure
that sufficient air circulation through
the cowling is provided. As a basic
reference, the outlet area should be 3
to 5 times the area of the inlet area to
provide adequate cooling.
Ignition System
Saito gasoline four-stroke engines
come with Saito’s own ignition system
composed of the ignition unit, cord for
sensor (black and white), cord for earth
to ground (green) insulated plug cap,
and cord (black and red) for connection
to a battery (not included). You will also
need to secure an on/off switch (safety
switch system). The switch must be
S P A R k P L U G A N D C A R B U R E T O R
5
4
F U E L A N D I G N I T I O N S Y S T E M
Figure 2
capacity of more than 1,000mA. Be
sure to mount the ignition system in a
location near the engine and away from
the receiver to prevent any unwanted
interference. Please refer to the
diagram below.
Spark Plug
NGK-CM6 (SAIG36120) is the
standard-equipped plug with the FG-36.
The FG-20 comes with Saito's own
1/4-32 spark plug (SAIG20120). When
needed, please replace with identical
appropriate plugs.
Carburetor
The carburetor used on gasoline four-
stroke engines are exclusive to Saito.
Since they have a negative pressure type
fuel pump, the engine can be mounted in
any position.
CAUTION:
If fuel remains in the
carburetor after flight, the components
made from rubber, such as the
diaphragm, will deteriorate over time.
After a flying session, it is best to
remove any fuel remaining in the carb-
uretor by disconnecting the fuel line and
Figure 4
NGK-CM6
Spark gap = .7-.8mm (.024 - .028 in)
1/4-32
Spark gap = .4 - .5mm (.016 - .020 in)
Figure 3
14387 SAI FG_20andFG_36 Manual.indd 4-5
12/16/08 2:09:12 PM