Still involved with the Mercury Montclair 292 1955 . The current owner has had a total of 4 Precision pumps installed on this 292 . Only 1 operated at all and that pump would only flow enough fuel to barely keep the engine running at idle .
As per the advice of forum members , I convinced the new owner that the solution to his fuel supply problem was an FE fuel pump . I did install an electric test pump to verify the fuel tank and all lines were clear and supplying clean fuel .
I asked the new owner to call Summit and order an Edelbrock fuel pump for a 1970 390 ford engine , we got that and installed it in minutes and fuel pressure and supply is now correct .
Finally , we took aprts two of the Precision M 34004 pumps to figure out why it seems 90 percent of folks on the net say the pumps do not work . Internally there is a contact point at the pump arm that is put in from the factory just a LITTLE bit off from what it should be . There is no way with the amount of travel available from the eccentric on the camshaft that these pumps could ever do anything . Sorry about that .Easy to tell once we got the Edelbrock  FE pump side by side with the off shore pump , easy to feel and see the difference in the arm operation and easy to see the Edelbrock would do the job the off shore could never do . The ofc shore fuel pump arm moves 1.6 inches and does not even begin to move the diaphragm inside the pump , That pump will pump if you move the arm a full 2.8 inches , ha ha, good luck on that . 
once again thanks for the help to us from the forum answers and members 
Joe in Tampa 

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