Fuel pump on B&S

Thanks. The tractor is a John Deere LA125. jdparts.com has a diagram and shows the fuel pump, but it is not very helpful (to me at least).

That third hose connects to the crankcase and uses the alternating pressure vacuum to operate the pump diaphragm. So make sure that third hose is connected and in good shape.

Priming it won't hurt but should not really be necessary.

You are corect in the third port goes to a vacuum port, so to speak. The pulses from the engine crank case are what makes the pump diaphragm "flutter" thus pumping the fuel. Check that your hoses are in good condition first as that woud be the most likley suspect at this point, and generally there is no need to prime the pump. If all the fuel drained back into the tank when you changed the pump it might take a bit to get it back up to the pump.......Midnite

Once I got some good light I found the vacuum line had fallen down in the crack behind the engine. Once reconnected, the mower worked just fine. Thanks!