If you wish to remove the dive as indicated in the pic, you can't without destroying the pump, thy are made not to be repaired, if the seal is leaking you will have to fit a new pump.
mark (mhpautos)
Sep 2, 2010 at 1:25 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.