Small Engine Troubleshooting Problems? Ask a Mechanic Now.
You have spark at the plug?
With spark, fuel , do you have compression? No compression, valve may be stuck. If you have compression, fuel and spark, the timing belt may have slipped and belt needs to be replaced and engine retimed.
Just put finger with rag over the spark plug hole, should have enough compression to move your finger.
Ok, if that doesn't do it, the timing may be off.
Here is timing belt .