... lower valve guide and upper valve guide suitable for oilwell, emsco, gardner denver,etc. Our lower valve guide and upper valve guide suitable for oilwell, ... .E.M. interchangeable mud pump parts for ALL major pumps. Our mud pump ... for Brewster, Continental Emsco, Ellis Williams, Gaso, Gardner Denver, Liners, Pistons, IDECO, National, Oilwell, OPI, Skytop, Wheatley, and Wilson. lower valve guide ...