If fitted, chack the anti-run-on solenoid on the bottom of the carb bowl. Chack it is a) connected, and b) has battery voltage when switch in 'ON' position. Spray WD-40 into carb (filter removed) while cranking. If engine starts, ignition/compression is good - concentrate on a fuel problem.
phil_saunders(a)bigfoot.com
Phil Saunders, May 2011