Saws usually flood for a couple of reasons, either dirt under the metering needle in the carb causing it not to seat and therefore allow fuel to literally run into the engine, or the needle tab has been set too high so again it doesnt seat, this would show up by the adjusting screws needing to be set nearly all the way in to allow the saw to run, but as a new carb has been fitted both should be ok, although no gaurantee.
Or it may flood on restarting if the spark isnt strong enough to ignite the fuel mix, especially at starting speed, worth checking, try reducing the plug gap.
Finally if the fuel tank breather is not working properly it can cause the fuel tank to over pressurise which again could cause fuel to be forced past the metering needle in the carb.
The only other possibility is that the engine is lacking compression and therefore simply will not start with the result that you constantly get a wet plug! obviously worst case scenario there.
good luck
Paul
p.sharman horticultural engineers
paul sharman
March 2011
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