O.S. engine GT120THU, Instruction Manual

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(5) With a gasoline engine, passages in the carburetor are narrower than that of a glow engine, therefore it is
very sensitive against foreign materials such as dust. It is suggested to use optional accessory Super Filter L
(Code No.72403050) when filling a tank in a model from a container for transportation or storage.
14. BREAKING IN AT FIRST TIME
Breaking process on the bench is not necessary for this engine since the engine is broken in for 10 minutes at
the factory before the shipment. But you need to keep in mind the several instructions as follows.
(1) Run the engine in rich adjustment during breaking in.
(2) Use the fuel at 25:1 mixture ratio with the oil you are using for actual operation.
(3) Break in the engine mounted in a aircraft with actual flying.
(4) The flying during breaking in is mainly hovering. Do not fly with additional payloads.
15. START-UP INSPECTION
Pre-operation inspections should be done as shown below.
GT120THUinspection before operation
Items to be inspected Inspection contents Method
Engine installation Check if the engine is mounted correctly and if there is no loose screws
and bolts. Visual
Silencer mounting Check if the silencer is mounted correctly or there is a loose. Visual
Air cleaner Check if the air cleaner is firmly fixed and if there is foreign material on
it. Visual
Propeller, clutch,
cooling fan Check if the propeller, clutch, cooling fan are mounted correctly and
there is no loose screws and bolts. Visual
Exhaust pipe Check the exhaust pipe if there is foreign material in it. Visual
Cooling air passage Check the air inlet/outlet if there is foreign material. Visual
Plug cap Check the plug cap if it is fixed firmly to the spark plug. Visual
Ignitor high tension
cord Check if there is wear and tear out, or dirt on it. Visual
Fuel tubes Check if tubes are frayed, kinked. Visual
Check if tube clips are fit firmly. Visual
Electric wirings Check if there is no cut, wear, and dirt. Visual
Check if all connectors are firmly connected. Visual
Oil leakage Check if there is oil leakage from an engine. Visual
Linkage Check if rod ends and link rods are firmly connected. Visual
Check if servo horns and servos are firmly fixed with screws Visual
Remaining fuel Check if the fuel tank is full. Visual
Mixture oil Check if gasoline and oil are mixed at correct rate. Visual
16. HOW TO START THE ENGINE
(1) Inducing the fuel
① Turn on the transmitter.
② Turn on the receiver switch.
③ Turn off the ignitor switch.
④Close the choke valves of engine.
⑤ Open the throttle valve by 10 degrees from the fully closed position (the first idling position).
⑥ Use a starter to run it until the fuel coming through the inlet of carburetor.
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.