Have a two year old Echo blower - PB-230LN. When I first start the blower and use for 20 minutes, works fine. Go mow the lawn which takes 30 minutes. Try to restart the blower and it will not restart. Prime it and pull cord it starts but then dies. I've replaced fuel lines and gas filter. Dumped gas and refilled. Took bubble primer off and look for clog. No luck. Help!!!!!!!!!