Try new spark plug. Yes a new spark plug can be bad too. Never had a problem with Autolite but NGK are a pain for that. If that doesn't work your air gap is set wrong for your coil to flywheel. It is either too far away from the fly wheel or touching. Doesn't take much to not spark if touching. The most miniscule fleck of rust stuck to the magnet on the flywheel can touch the coil and bridge the gap. You only have an air gap of .010 so anything that size will bridge it. You need a feeler gauge. The air gap needs to be set at .010 where the magnets on flywheel are aligned with the coil. make sure both legs are at .010. When set correctly you should have slight drag on the feeler gauge but don't let the magnet fool you unless you are using a pure stainless steel or brass feeler gauge the feeler gauge will magnetize to the flywheel giving a false sense. Be ABSOLUTELY sure that your gap is right and make sure those bolts are good and snug. If that coil comes loose and goes into the magnets on the flywheel it will break the two posts off that hold the coil and then unless you fix those posts the engine is garbage.
Luggnutt
February 2012
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