ORIGINAL: jester_s1
You can check for leaks without taking anything apart. Get a straw that fits the carb opening, and put the piston just below TDC. You should be able to blow air in the carb without it leaking out anywhere except maybe the muffler. If it does, put the engine in a bowl of water and blow, looking for the bubbles.
Eh most glow engines will purposely "leak" around the bearings, to keep them oiled.
Usually the amount is low enough not to cause engine problems, but this often throws newbies...