Re: starter problem
The balance of the flywheel has no bearing at this point.
It's either a 151 or 168 tooth gear and the right starter needs to be matched with the right ring gear. You can worry about the balance after the engine cranks.
Assuming you are using Chevy parts, for the 168 tooth gear, make sure you have a small nose starter (iron, same size starter bolts, if the bolts are different sizes, you have the wrong starter) and the gears have to mesh better than halfway so that the teeth aren't broken off. Some folks unbend a large paperclip to establish a .060 mesh depth between the gears. Measure at the valley of an enmeshed gear pair.
Aftermarket starters use same size bolts too, but mount the starter in different holes for alignment (consult with aftermarket starter manufacturer)
If you are using the right (Chevy) starter, you may want to inspect your ring gear for missing or worn teeth.
Last edited by mahunt; Jun 29th, 10 at 09:26 AM.