I was gonna answer your email but probably other people can benefit...

You've just discovered why it's a good idea to disconnect the battery... I found that out long ago when I welded my wristwatch to the back of a cigarette lighter. You wouldn't believe how much that hurts, & when I finally yanked it off I discovered all kinds of sharp pointy things under the dashboard.

If you've ever taken apart any kind of electric motor, you'll find that a starter isn't that much different. Fine little wires wrapped around the poles of the rotor and around the poles of the stator. My guess is some of those have burned up. Maybe a Helm book says what their resistances are supposed to be? Just guessing, but those might not be available as spare parts.

I've taken starters apart, but they just had worn brushes that didn't touch the commutator any more. I think you just have to take yours apart & look for burned components. I can't automatically say which parts burned up.

 

LOL.

Dude, I once arc welded a box wrench to my neuspeed strut bar. THAT woke my *** up you can be sure. There is a reason the positive terminal should always be covered by that red rubber thing.