balsacrackerx10:

Check the glow plug and the head screws. Have you checked to see if the piston moves? While the plug is out hold a toothpick in the plug hole, turn the crank and be sure the piston does move. Very rare but I've seen a crank break cleanly at the intake port, prop turned nicely but the piston didn't move.

Most likely it's just dry from your cleaning it. Try starting it and see what happens.

Bill.