Instruction manual

Spark Plug
1/4-32
Sparkgap=.4to.5mm(.016to.020in)
The FG-14B and FG-20 come with Saito's own
1/4-32sparkplug(SAIG20120).Whenneeded,
please replace with identical appropriate
plugs.
Carburetor
The carburetors 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 carburetor by
disconnecting the fuel line and running the
engine until it is dry.
Do not needlessly disassemble the
carburetor. If you experience problems with
the carburetor, return it to the Saito Horizon
Service Center.
Fuel
Mix a ratio of gasoline to oil of 20:1for •
break-in and continuous operation on all
engines.
A mixture of high-quality 91 octane •
unleaded gasoline and a reliable high-
quality 100% synthetic oil for 2-cycle
enginesmustbeused(werecommend
EvolutionOil,EVOX1001Q).
Note: With the use of an oil mixture of 20:1,
it is normal to see a slight amount of carbon
buildup on the exhaust valve itself.
This is why it is so very important that you
use a high quality synthetic oil and not
just the standard 2-stroke oil you may be
currently used to using in your 2-stroke gas
engine. We have found that although these
2-stroke oils work well in their intended
applications they can cause a build up of a
gummy type residue on the exhaust valve
in a 4-stroke gas engine and this potentially
leads to the need for sending your engine
in for service as the exhaust valve begins to
stick and not seal properly.
The high quality Evolution oil we recommend
using will still build up a slight amount of
carbon, but we have found that this build up
is easily flaked off during normal operation
of the engine and will not create the
aforementioned typical gummy build up.
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orHAN143)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.
Figure 2
Fuel Tank and Plumbing
Figure 3
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.
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 carry a rating of 3 amps
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.
Saito recommends the use of a 5-cell battery
with a voltage of 6V and rated to a minimum
1000mA.
Figure 4
8 FG-14B/FG-20 FUEL AND IGNITION SYSTEM
FG-14B/FG-20 SPARK PLUG AND CARBURETOR 9