Fuel & Break-in
◎Use low to middle octane gas for break-in. Use the propeller same as
flight.
◎Use qualified 2-stroke petroleum based or synthetic oil with a mixture
of 25:1 to 30:1 in the break-in process。
◎With this fuel mixture ratio and regular needle setting, run the engine
for 1~2 hours. Too rich needle setting, which may cause misfiring or
erratic running, is not suggested.
◎After break-in, you can use a 2-stroke synthetic oil with a mixture of
30:1 to 35:1.
Needle Adjustments
◎A Walbro WT664A carburetor or equal carburetor is adopted. The
carburetor has two needles, which are low speed needle and high
speed needle. Low speed needle is effective through the high speed
range, while the high speed needle is not effective in the low throttle
status. Both needles are effective in the mid speed, but the low speed
needle is more effective. Default position of high speed needle is 1 ½
turns from full closed, as well as low speed needle is 1 ¼ turns.
◎For fine setting, please tune the engine for maximum RPM with the
high speed needle by using a tachometer. Then richen the high speed
needle until the motor runs 100~200 RPM less than the maximum
RPM. Now the engine is slightly rich on the high speed needle.
◎Furthermore, keep the engine at idle for 45~60 seconds. Check that
the idle RPM remains constant or not. If the RPM drops and the
engine stops finally, the speed needle should be too rich. Lean it until
stable idle status is achieved. Then check the transition with advancing
throttle quickly. The engine should make steady power immediately
without any hesitation. If the engine sounds hesitated to response,
please check the low speed needle again.
Eagle Master Engine EME 55II User Manual ‐6‐
