crankshaft spline machine rebiuld

Neccessary depends on your crank's condition. Flywheel fix is often just a matter of replacing soft, stretched bolts with grade 8 and 'putin' the torque to em. If it won't stay put then, that's when you need the machine shop.

Work hardening is not a reason to rebuild the splines. Worn off is the only reason to rebuild the splines - it sounds like the book you're reading would also demand that one drain, flush, and replace anti-freeze yearly. Go ahead and finish reading it, but ignore everything between the front and back cover as not even the author could afford his own advice.

In my case, I determined this needed to be done. The splines inside the clutch driver appear to be in great condition, but with regular use it appeared the crank splines could round off entirely. That would have put the drive disk at risk of damage as well, and call for another engine tear down later on. The driver is being used as the pattern for the repair, so the splines should match perfectly when its done (even if the driver is worn some). I'm planning to use the B regularly to for some hay raking, miscellaneous projects, and an occassional tractor pull. Its also expected to make several HP over stock, so it wasn't worth the risk to put it back together already worn like that.