Broken intermediate shaft pulley

[peterman]

I cannot find a single instance of this happening to anyone else online. Which makes me think think theres some funky things going on inside.
Relavent specs:
Fresh rebuild
M50b28 crank
Je pistons
325i rods
Replaced the intermediate shaft bearings - spun freely but no excessive play.
Pulley is the sintered version
I havent pulled it apart yet but looking for thoughts. Has anyone seen this happen before? The only thing I can think of is that the pump locked up. I had a good 40 psi at idle.

[hasa]

Does the shaft pulley turn by hand?

[digger]

Maybe bolt came loose (insufficient preload or it wasn't seated correctly) and rattled around pounding the pin and bolt. I have seen the pins broken off before.