[Andrew Rowe]

Do exactly what Richard says after assembly , and this will confirm operation of pump. Just remember, when you reassemble, compress the diaphragm by holding the lever up BEFORE you tighten the top screws up. By checking the pump action will also indicate that you have the valves around the right way as well as diaphragm action. Other than that the problem will lead you to the length of the push rod. You can sit the pump on the engine , but do not bolt down, turn engine over to observe the lift of the rod and the effect this is having on the pump, it should push the pump up and down when not bolted to the manifold, also check the condition of the gasket under the lid,to seal and also any holes in the main diaphragm, as this will also lead to faulty operation, Cheers Andrew.