Its getting good orange spark ,put gas in carb and it won't start ,mag was rusty but sand it clean ad replaced at 14ths pull 5 or 6 times then it pull back fire I think, little puff comes out carb then half way through pull it lock up or pulls rope out of hand but doesn't really lock up cause it will go ahead and pull
the spark should be blue, so check that the flywheel is correctly positioned, if it is slightly loose remove it and the woodruff key and smear some fine grinding paste around the shaft and smooth the surface with the flywheel in position(the same as you would grindig valves)refit tight. also make sure the cutting blade is positioned correctly.
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