Depends on the pump, your best bet is turn off oil at tank, clean all filters, then find oil tap nearest boiler. Turn this off, then oil back on at tank....now disconnect flexible oil line at burner, put into a container, turn oil back on and bleed through until no more air comes out. Reconnect line, ensure oil turned back on, hit lockout, should be sorted. You can bleed on the pump, but this can be messy if you don't know what you are doing.
Jim the boilerman, October 2012
