Since the lower half is zinc, do the following:
(A) Remove the two pump check valves from the inside bottom of the bowl. These are the two closest to the pump
(B) Make a plug the same thread as one, and plug that hole.
(C) Make an open plug the same thread as the other, and tap for a grease fitting. Place this in the other hole.
(D) Apply grease from a grease gun to the fitting.
(E) Remove pump, 2 plugs, and wash out the grease.
It would have been easier if it were cast iron.
Jon.
