[Tom Cimino]

When I read your post, the first thing I thougt was "I wonder if it's a Holley pump." I've had two Holley chrome pumps on my small block fail. First one broke the rod between the pump arm and the diaphram. Of course, dead on the spot. The second had one of the one way valves pop out and then got wedged back in. The motor stalled like it ran out of gas, but then caught and ran the rest of the way home. I found the valve wedged in it's seat kind of crossways but in enough to run. I quit fooling around and bought a Carter pump. Not chrome, but it's been working for over ten years. There's one bolt on the bottom of the pump. Remove it and the bottom plate and inspect the one way valves.