Fuel pump issues on a 1977 175hp johnson

[mvs57]

replaced the fuel pumps.....engine started and ran for 3 mins then stopped....can not get it to pump fuel in the lower pump to upper pump..100% sure getting fuel to it....when I ordered new pumps they were the same....the old ones were different pumps..I questioned the parts supplier said the new pumps would work..Is there something I am not doing right ..or am I being told wrong by supplier...

HELP!

 

[Joe Reeves]

Re: Fuel pump issues on a 1977 175hp johnson

The pumps should have three fittings... incoming fuel fitting, outgoing fuel fitting, pump to crankcase fitting. Is this what you have?

If the proper fitting type pumps, have you tried switching the pumps? Did this make any difference?

The bottom pump crankcase fitting... remove the hose from the crankcase and crank the engine over to see and feel what kind of pressure flows out when the piston is in the down mode. If weak of no pressure, suspect a failed reed plate leaf valve which would allow the pressure to escape out the carburetor throat... OR (and hopefully not) a blown piston.