O.S. engine GT120THU, Instruction Manual

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O.D.φ6.0
～
6.4mm). The tubes should be replaced periodically because they harden with age. A tube
in a fuel tank should be replaced in 6 months to one year.
(6) The fuel tank should have three separate tubes including one exclusively for refueling. Use φ0.6
～
0.8
mm the stainless steel wire clips to fix each of the tube.
11. FUEL TUBE
(1) Clip the joint part of each tube with φ0.6
～
0.8 stainless steel wire or hose accessory clips.
(2) Piping between the fuel tank and fuel filter, and the fuel and filter carburetor
① Use the fuel filter # 78300000 as shown in the Fig. 6, be
sure of the direction since it is vital for the fuel filter.
② The length of the each tube should have a margin of
10mm in addition to the shortest connection distance.
③ Fix the tubes firmly not to be moved by flowing wind
pressure, be careful not kink the tubes also.
Fig 6.
12. WIRINGS
(1) Wirings of the throttle servo, the choke servo, and the starter switch
①Connect the throttle servo to the throttle channel of receiver and set the direction of servo arm
movement, the fully open / close position (end point adjust) using functions of the transmitter.
②Connect the choke servo to an auxiliary (aux.) channel of the receiver and assign the channel to a 2 or 3 –
position alternate toggle switch. Set the direction of servo arm movement, the fully open / close position
(end point adjust) using functions of the transmitter.
③Connect the starter switch to an auxiliary (aux.) channel of the receiver and assign the channel to a 2-
position momentary toggle switch. Set the direction of the switch, the fully open / close position (end
point adjust) using functions of the transmitter. The starter switch determines on or off at the threshold of
1,500µs PWM signal, which is neutral position. So when you set the fully open / close position, 1,500µs
PWM signal should be included in the range of turn on / off the 2-position momentary toggle switch.
(2) Wiring of starter switch battery
Charging the starter use the its equipped XT90 type concave connector, the voltage of starter battery is 11.1
～
16.8V, the capacity of it is needed to be over 2,200 mAh, use the more than 35C discharge capacity
power supply to charge it.
Attention:
Do not run the starter for more than 3 seconds at a time. Give the starter at least 3-second interval for
continual use. Otherwise the starter, lead wires and battery may get damaged.
(3) Wiring of regulate rectifier output
The output of regulate rectifier has two black lead wires and 14AWG wire which are pre-tinned without any
connector. However, you can wire it yourself depends on the equipment or connector you are using.
13. FUEL AND OIL MIX
(1) Use regular gasoline. (No need to use high octane gasoline.)
(2) Alcohol based glow fuel cannot be used in this engine because it cannot make the engine work properly,
and also the internal carburetor plastic parts will get damaged.
(3) Use high quality 2-stroke engine oil available on the market because some oil might accumulate carbon
residues in the combustion chamber and the exhaust port after several-hour operation and cause a
trouble. Check the combustion chamber if there is unusual residue in short period.
(4) Follow the oil manufacturer’s recommendations concerning the mixture ratio of gasoline and oil. If
there is no recommendation, mix with a 25:1 ratio. We have checked and approved the following oil
mixture ratio. ZENOAH 2-strokes genuine oil FD (50:1), KLOTZ ModeLube® (50:1), Castrol Power 1 – TTS
Racing (50:1). (This does not mean we guarantee the quality of these oils.)