5. Ignition system
*Be careful of possibility of electrical shock as it generates high voltage.
*The unit includes a plastic clip to hold the connectors and spiral tube to protect each wire.
The ignition system is designed to match SAITO 4-stroke gas-engines with automatic advancing system.
However this ignition system is designed to be an anti-noise product, please isolate it completely from the receiver, servo, and
battery to avoid a radio-interference trouble. Moreover, it is desirable to utilize a noise filter (line filter). Especially, each switch
(for Ignition and for Receiver) should be isolated and set far from each ones.
Caution: A gas-engine generates a noise which has an adverse effect on RC adjustment. Please be sure to carry out a noise
check each time while the engine is running before flight. Since a noise which occurs during flight may lead to a large-scale
accident, please carry out a noise check without fail. As a simple method, after starting engine you can check by removing
the antenna of the transmitter and operate it about 50m away from the airplane. If there is no malfunction, it is normal.
The function of each cord;
(1) Plug cord (meshed high tension cord)
As Fig.6 shows there are three cords available for three cylinders. Make sure to attach each number described on the main
unit to the cylinder. (Refer to Fig.2 regarding cylinder number). When you put on the plug cap, insert deep into the plug to
avoid coming off during flight. And then pull the plug cap to confirm that it won t come off.
(2) Sensor cord (Gray cord with exclusive connector)
Connect with the cord from the sensor attached to the engine.
(3) Battery cord (black/red cord)
Please use the fully charged battery that has adequate spec. (6-9V, more than 1000mA is recommended.). Between the
battery and main unit, make sure to set an ignition switch whose capacity is higher than 3A.
(4)Tachometer cord (black/red/white cord)
Connect the digital tachometer (Option). Otherwise the connector is normally vacant.
6. Spark plug
NGK CM-6 spark plug is the standard
Dimensions are as follows;
Hexagon width: 14mm
For replacement, please replace with a
reliable product as NGK CM-6.
Since SAITO 4-stroke engine uses mixed
gasoline, please decide the numbers of
flights by yourself to clean the spark plug.
Please replace, when it is degraded.
(Consider the plug as consumable.)
Equipped with a suitable carburetor by technical cooperation with Walbro that provides highly reliable carburetors for other
gas-engines. Because of its structure, in some case performing Air purging just before flight is recommended. Regarding this
please refer to the attached document.
Note ： To avoid entraining air lock in the carb, it is better to leave fuel in the carb after running. But in such way of storing,
gasoline accelerate degradation of rubber parts such as diaphragm.
The carburetor for a gas-engine is elaborate and delicate. Please never disassemble it. If it s out of condition,
please consult the shop you bought from.
Method of choking (For manual start only)
(1)As shown in Fig.7, pass the choke bar (with M3.5 thread on its tip)
thorough the hole on the cowling. Then turn the bar to insert into
the M3.5 internal thread at the center of the throttle lever.
(2) Pull the choke bar and fix it by using a clip or clamp as shown in Fig.7
so that it may not go back to the previous position.
(3) Grasp the prop by hand and turn it to the forward direction(CCW) for
several times, until the carburetor generates hissing-like sounds.
(4) After hearing this sound for about 5 times, quickly flick the prop by
cranking it some 10 times. Then choking is completed.
(5) Remove the choke bar.
(6) Power on the ignition system and open the throttle valve about 1/4
from the full close position by using the throttle stick. (Starting with
excessively opened throttle is dangerous since the airplane jumps
(7) Flick the prop quickly and engine will start. If the engine doesn t start, repeat the choking procedure (1) to (6).
*After starting, run the engine for 10 to 20 sec to warm up.
5cell-NiMH or 2cell-LiPo
ﬁxed by clip
Switch (not included)
Capacity: more than 3A
M3.5 thread for
(Move to the left)