Oil pump won't prime

I'd have to agree w/ DJVCUDA. I'd get a new cap & then you would have to get it align honed. That old cap is no good now. whatever caused it to break had to put some stress on it & where there's stress theres distortion to the metal surface where the pump seats & even if it could be repaired you would have to have it rehoned. It might be a good time to upgrade the bottom end to 4 bolt mains since you have to do the line honing anyway.