I have OD 46x, with abt 2 flights on it, last week it was flying great, but yesterday it started quitting when ever plane goes nose down during flight, also on ground from low to hi transition is just wobbled and quit. Fuel is same as was last sunday. Plug also changed, tank clunk pipe also changed but same situation, pls guide.

Lean.

Originally Posted by Bunky F. Knuckle

Lean.

Low needle or hi or both?

Tuning glow motors is rapidly becoming a lost art. You didn't say if nose down is also at idle. Also are you talking about a vertical downline(nose pointing straight down) or just when you lower the nose in flight?

Low or idle setting: On the ground just raise the nose up about six to ten inches off the ground while at idle. If it loads up and dies, the idle setting is too rich. If it speeds up a little and dies, the idle is too lean. You want to be able to hold the nose up like that and not have it change. This is probably your problem.

Main needle valve: Glows tend to lean out in the air and more as the tank gets low. People tend to try to lean them way too much on the ground. I like to have them just on the verge of two-cycling on the ground run up, then they will take care of themselves in the air. Getting that last few RPMs is fine if you are pylon racing, otherwise it can cause a lean run and ruin a motor.

Hope that helps.