FQ650
Engine will not start:
Possible cause: Bad fuel; tiller stored without treating or draining petrol, or refueled with bad petrol.

Drain fuel tank and carburettor, Refuel with fresh petrol.
Correction
Possible cause: Bad fuel; tiller stored without treating or draining petrol, or refueled with bad petrol.
Drain fuel tank and carburettor, Refuel with fresh petrol.