This is the 70T Carburetor for the O.S. Engines GF30 Gasoline Engine, OSMG0798|
Fully assembled and ready to install
70T Carburetor with Throttle Lever
Needle Valve: Slowly open throttle fully after engine is started.
Close needle valve in 30-45° increments. When RPMs start to
decrease, close needle valve 60-90° further. Open slowly at 15°
per second until maximum RPM is obtained, then open 60-90°
further from max RPM point
Mixture Control Valve: Preset at nearly best position. Do not adjust
until break-in is completed
Start engine & open throttle fully to warm up engine. Set idle
around 2000RPM from throttle trim on transmitter. Move throttle
from idle to fully open several times & measure idling RPM with
tach. If idling is unstable & RPM decreases gradually, the
mixture control valve is set rich. If RPM increases at idling
or engine doesn't respond quickly, the mixture is too lean.
Stop engine & turn mixture control valve 30° clockwise if
mixture is too rich, or 30° counterclockwise if too lean.
Repeat above procedure until idling RPM becomes stable.
For final main needle adjustment, set idling RPM by transmitter
depending on prop size and aircraft model. Move throttle stick to
full throttle quickly and then to full throttle slowly,
adjusting needle 15° counterclockwise if too lean, or 15°
clockwise if too rich.