It should fire up O.K. If not, and you don't mind pulling it apart, take the backing plate off, (and the plug out) and flush the engine out with some fresh fuel. Just pour a little in the back of the engine, turn the flywheel over a few times, drain it, then put her back together. This will help flush any "gluggy" residue out of the engine and make it easier to turn over.
Some R.C. stuff.