You really need to ask the assistance of someone who has experience with model engines. For example: if the engine cuts when the plug lead is removed it is often (but not always) due to an over rich idle setting. Also, you should not adjust the carburetor to alter the oil coming out of the engine: the oil you put in via the fuel will come out regardless of what you do to the carburetor.

WD 40 is not a good engine lubricant and I've heard it can actually damage plugs.

Ask someone knowledgable to give you a hand - don't make the mistakes yourself. It could even be dangerous.