As HRL said, make sure the 3 riveted pieces are in alignment. You can see the wear mark on the cam and pump arm. Only one of the pieces was able to contact the cam. This was a new pump (gold top) that lasted a few hundred miles. It's replacement (silver top) didn't work at all from the get go.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)