is the b18c1 crank pulley supposed to have grooves in the center hole all the way through?
or are they supposed to taper off halfway?

this is what mine looked like after i pulled it off

 

Yours is definitely not normal - the grooves should continue from front to back. There shouldn't be any of the wear that yours is showing. We just recently pulled one off of a motor with around 50k on it, and the bore of the pulley looked brand-new. It almost looks to me like the key broke and ate away at the bore.

 

thanks for the confirmation.

anyone know of a cheap place to buy one?

 

i had one that looked like that.

the key broke and the pulley wabbeled and wore itself down like yours

 

My old P72 Crank Pulley with good splines.

 

Hmmm...I wonder how your crankshaft is doing. The splines are still centered so I suppose the vibrational dampening is still functional (= nevermind).