Re: wont pump fuel
Is this the in-line 6 with two fuel pumps?
When you replaced the diaphragms did you use the fuel pump rebuild kits that included the new check valves?
Generally when squeezing the primer bulb keeps the motor running the problem is either air sucking into the system after the bulb or bad fuel pump(s), like leaking check valves in the fuel pump.
Disconnect the fuel line after the fuel pump, install a clear hose, crank the motor and watch the fuel stream.
If either pump fails, get a complete pump rebuild kit(s).