I was breaking in my new OS .15LA today when I noticed that there was a small amout of fuel coming out at the top the engine. So I stopped the engine checked the tightness of the glow plug and the head blots and they were fine and tight enough. And my glow plug does have the washer on it. (the glow plug has not been cross threaded)

Has anyone else had this prolem and where could the fuel be leaking from?

are you sure that you have the correct glow plug? might want to make sure you have the recommended plug.

I just double checked so i do have the right one, but thanks.

If you were running it rich, there may be fuel spray coming from your carb, making appear as fuel was coming from the head. Run it again and take a piece of card board and hold it between the carb and the cylinder. If it gets wet, then you know the answer! Second, make sure your muffler is tight and is sealed against the exhaust.

Hope that helps!

there have been instances where the glass insulater in the plug has craked or is leaking and can allow fuel to pass thru.

Hello; I think it might be fuel spitting back frim the carb, being blown back over the head. Try wrapping some tin foil around the head for a quick run to see if that's it. The muffler joint is another possibility. I have an old FP 40 that still does this, yet it runs just fine. I have an Irvine 40 Diesel that leaks oil from the hole the setscrew for the contra-piston lock down, is. that oil is coming past the O-ring on the contra piston, so you don't have one of those. Those two strokes are oily things, however, they oil by total loss, so the oil has to go somewhere. Exhaust diverters do a little to keep the oilyness down a bit. Since I started flying electrics, I appreciate not having to mop everything down after a days flying.

Also check the fuel lines. I've seen very small pin holes that were almost invisible do a bit of squirt-gun action once the engine starts.

Hey guys I found the problem. I took the cylinder head off the engine and saw there was no gasket between the block and the head. I know enough about engines to know there should be one. To be on the correct side of things I double checked by looking at the engine breakdown in the O.S. manual and sure enough there is suppose to be a gasket. So I called O.S. explained the problem and they are sending me a gasket by mail.
How awsome it is to have a great customer service that Tower,GB, and Hobbico all have. This is the second time they have helped me and they have been great!!!!