I had a simular problem, if when you hit the primer it does not fill up it is the gasket between the carb and the engin, i just ordered a gasket kit from a store and that fixed the problem, plus now i have a replacement for every gasket.
Check the fuel filter, air cleaner, and muffler for plugging. Check the fuel lines for condition and replace with original rubber lines, not plastic if needed. Check the carburetor fasteners for tightness including those holding the carburetor to the cylinder. If the two jet screws have not been adjusted, they should be ok. There is a chance that the diaphragm in the lower carburetor chamber is hard, cracked, or has a hole. Also, check the fuel metering valve that the diaphragm controls for tip damage or dirt accumulations. Go to http://www.drystacked.com for a 12 page article on Walbro carburetor theory and troubleshooting which applies to nearly every brand of carburetor used in saws. Hope this helps!
Answers & Comments
I had a simular problem, if when you hit the primer it does not fill up it is the gasket between the carb and the engin, i just ordered a gasket kit from a store and that fixed the problem, plus now i have a replacement for every gasket.
Check the fuel filter, air cleaner, and muffler for plugging. Check the fuel lines for condition and replace with original rubber lines, not plastic if needed. Check the carburetor fasteners for tightness including those holding the carburetor to the cylinder. If the two jet screws have not been adjusted, they should be ok. There is a chance that the diaphragm in the lower carburetor chamber is hard, cracked, or has a hole. Also, check the fuel metering valve that the diaphragm controls for tip damage or dirt accumulations. Go to http://www.drystacked.com for a 12 page article on Walbro carburetor theory and troubleshooting which applies to nearly every brand of carburetor used in saws. Hope this helps!