O.S. 25 FP glow engine, 10% nitro fuel, 6x3 prop. Started up my plane and was letting it warm up on the ground at about 1/3 throttle. All of a sudden, after about 2-2 1/2 minutes, it jumps up to full throttle. I moved the tx gimble to idle & checked the carb and it was closed down to idle where it should be. I then died. I tried to restart and it didn't want to start at all. I put fuel down the carb after checking the plug, (which was okay), carb at idle setting, and finally it started and again jumped to full throttle!

What is going on? It worked fine minutes before.


I put my finger over the carb and it still ran! It absolutely would not shut down from full throttle! I finally pulled the fuel line from the carb and after about 10 seconds it finally turned off.

I noticed a little smoke coming from the engine it was HOT! but it has cooled down now and still turns over fine.

I now notice there is fuel underneath the plane and upon taking hte wing off I notice there is fuel inside the plane. I think I developed a fuel leak from vibration maybe. I pulled both lines off the motor, pinched one and blew in the other. I could blow through it. Yep definately a fuel leak at the rubber part where the brass lines go through.

But could the fuel leak have caused the motor to stick in high rpm?

What should I do now? Fix the leak or install a new tank and fire up again? Or is there another problem I need to repair before starting again?

TIA for anyones help.