The manuals say to remove the cam before removing the oil pump drive shaft but the cam seems to hang up on it, and the oil pump gear shaft won't budge. Neither Haynes or the Chevy shop manual refer to it in the cam or oil pump removal section other than to acknowledge it. I removed a bolt that looks like it holds the pump gear shaft in but the mounting might be frozen/rusted and rings like it's one piece when struck. Should I use my Extra Big hammer? Are their any plastic parts that could melt if it's heated?

another possibility is the cam has worn a lip so it won't pass through the bearing holes in the block. am I the only guy that's come across this?

ok in the next chapter in this exciting story we find our hero totally pissed w/ a broken oil pump gear housing that was treacherously made of aluminum which corroded (or something) and is still locked inside the engine block. He expects to drill down from the outside broken top and apply something explosive. if successful, a replacement will be sourced from ebay (or something). ... Stay tuned for the unexpected outcome!

 

ok ~ ok, the deed is done and it was extracted successfully. Since our hero is the default authority on this process, his advice is to not twist the oil pump gear casing because it breaks easily. instead, remove the bolt and just drive the whole gizmo out from the bottom w/ a piece of 1/2 inch water pipe or re-bar and a very big hammer, but don't hit it too hard in case it's cold welded or petrified. It'll pop right out (probly for sure), then the cam comes out no sweat. There actually was a replacement on ebay for $25.