Hi.

While flying my Hobbico Hobbistar 60 (using an OS .65 LA engine), my engine is showing a trend of stalling (completely stopping) after only a few minutes of flying. The fuel tank is full when I take off and easily lasts 10 minutes normally. The engine seems to stop after I climb vertically and then then pull the throttle back to near idle and use the vertical stabilizer to turn the plane so it's nose diving. The idle is fine (I assume) because it idles fine on the ground or at level flight.

I believe the fuel mix is ok, but I can't think of another reason why the engine is stopping. Could the engine be too lean or too rich? Could the fuel line not be reaching the fuel while I'm in a nose dive? Any suggestions?

If it quits like that when you are flying level WITH 1/2 or more throttle then it is probably too lean.

If it quits only during those maneuvers then I'd check inside the tank to see if the clunk line is straight. Sometimes they flip around to the front of the tank during a sudden stop(rough landing).

I would richen it about 1/8 th of a turn and try again. If it does it again then check the clunk line inside the tank for a pinhole.

The other thing you might want to consider is you may have your idle set low for landing and if so it might just cut with the nose held up n half tank. Either do not pull the throtle all the way back or set up a high idle flight switch. [ Personally I do not recommend the later as one day you forget, try to land on high idle, overshoot and hit the wall at the end of the field.]

He's got a wall at the end of his field? Strange place to build a wall.

This usually isn't an issue because the inertia keeps the fuel in the back of the tank. This is why you need to make that the clunk stays at the rear of the tank, if it flips to the front of the tank and gets stuck there your engine will die.

Ken

I'd let the engine run for a few minutes to warm up, then with someone helping tilt the plane straight up at full throttle and try adjusting the high speed needle. Then check to see how the engine transitions from idle to full. If it works good that way, then hold up again at full throttle then cut the throttle and see how it reacts. Also watch your fuel line when you raise it up, for air bubbles due to leaks or vibration.

Sounds like the air bleed is off a tad. Check page 25 your owner's manual and that will give you a good idea how to adjust your air bleed carb.