"The flywheel must absolutely
"The flywheel must absolutely be torqued to factory specifications. ON that model, I believe iit is 145 foot pounds but check that figure.
DO NOT use an impact wrench!
I strongly suspect that you atrateed the engiine with having that flywheel nut torqued to less that factory specifications. This results in having the flywheel key shear, throwing the engine out of time. Usually this prevents the engine from running at all.
However in your case I suspect that the flywheel has spun to a point where the timing is such that the ignition is being engaged in a reverse manner which would cause the engine to run backwards.
Remove the flywheel. If the key is sheared even slightly, replace it with the proper part numbered key (not something from a hardware store), and torque the flywheel nut properly.
Note that the flywheel and crankshaft tapers must be cleaned if scored etc. Have the flywheel key aligned straight up and down, not aligned with the crankshaft taper."
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