Fuel flow

[yimmyb]

I have a 1980 MerCruiser 5.7 MCM 260. If I put a small amount of gas down the carburetor the the engine fires until that gas is used up. I have replaced the fuel pump and the water separator. Being there are 2 ports on the fuel pump does it matter which one goes to the separator and which one goes to the carburetor?

 

[Bondo]

I have a 1980 MerCruiser 5.7 MCM 260. If I put a small amount of gas down the carburetor the the engine fires until that gas is used up. I have replaced the fuel pump and the water separator. Being there are 2 ports on the fuel pump does it matter which one goes to the separator and which one goes to the carburetor?

Ayuh,..... One is In, 'n one is Out,..... it matters,.... Alot,.....

 

[alldodge]

^^^ It's a suck and blow thing. Don't want to suck fuel out of the motor and blow it into the fuel tank

Look for the arrow

 

[Scott Danforth]

Hook up the inlet to a small fuel tank. Your anti siphon valve may be plugged, or the pump may have a ruptured diaphragm or the needle and seat may be stuck

 

[dubs283]

does it matter which one goes to the separator and which one goes to the carburetor?

Yes

As bondo says, it matters very much.

Please ensure there is an overflow/rupture port and connected line to the carb for diaphragm failure event