Right, i am deeply considering a petrol can and lighter!!

my new cam has a recess where its meant to fit to the pulley, my pulley also has a recess as its a vernier. When i took the cam out the recess on the pulley was on the bottom to get the arrow lining up with the mark on the top of the head.
i lined up the mark on the head to the arrow on the vernier but as i was tightening the retaining bolt nothing was there to stop the pulley just winding into the head, the nut didnt get tight just kept pulling the pulley in until it nearly touched the head??

Firstly are the grooves on cams in the same place as the ridges on other, and secondly if the pulley is just holding the cam via the nut, is that enough??


My god,, help me