Hello!
I have the Alpha 40 Trainer RTF that has the Evolution .46 Trainer engine and without any hesitation at all it completely just shuts off after about 10 seconds after start. The fuel line that runs from the mixture adjustment knob to the carburetor seems to have plenty of fuel going through it, even after it shuts off. Put brand new fuel in the tank and the problem still exists. Could this be a glow plug related issue? It starts beautifully, but after a few seconds it just shuts right off. Any ideas? Thanks

Sounds way too lean. Like it runs out the prime then dies. Start over with the needle setting. If you don't have the manual begin at 1 1/2 turns open. It should run from there.

IF it quits only when you remove the glow ignitor then it is a bad glow plug.

Ok I will try that tomorrow. She runs fine once the glow plug igniter is removed so it must be to lean! Thanks a lot

Originally Posted by trimble95

Ok I will try that tomorrow. She runs fine once the glow plug igniter is removed so it must be to lean!

If an engine keeps running with the glow-ignitor connected, yet shuts down when it is removed; it is too rich on the low-end.

Your trainer engine has limiters on both the high-speed needle (it is not a knob!); and on the low-speed needle.

The low-speed needle is in the center of the throttle arm. Its proper adjustment is crucial, since it controls the behavior of your engine from idle through ~75% throttle.

The high-speed needle only controls the engine's top-end and has virtually no effect at part-throttle settings (unless it is closed way too far).


If the low-speed needle is too open (i.e. the setting is too rich), it may need the ignitor to run, will load-up with excess fuel and stumble sputtering when the throttle is advanced.

Originally Posted by DarZeelon

If an engine keeps running with the glow-ignitor connected, yet shuts down when it is removed; it is too rich on the low-end.

Your trainer engine has limiters on both the high-speed needle (it is not a knob!); and on the low-speed needle.

The low-speed needle is in the center of the throttle arm. Its proper adjustment is crucial, since it controls the behavior of your engine from idle through ~75% throttle.

The high-speed needle only controls the engine's top-end and has virtually no effect at part-throttle settings (unless it is closed way too far).


If the low-speed needle is too open (i.e. the setting is too rich), it may need the ignitor to run, will load-up with excess fuel and stumble sputtering when the throttle is advanced.

Thank you, I will mess around with it!

Hotter plug and richer main needle setting.

Re-tune and fly.

I assume obvious culprits (air leaks, pinholes in fuel tubing, compression leaks) have been checked and eliminated.