I had a crank pulley problem on my car,
the pulley came loose, and the keyway got a bit shagged, i'd say there would have been some vibrations problems going thru my engine for a few 100km's
this was just before cylinder 6 copped a hole down the side, which would have been hard caused by leaning out as it has a very very fat tune.
it will be very interesting to see if i have any problems with my N1 pump when i pull it off. it has seen alot of abuse i guess photos will follow when i get around to it.