Carter fuel pump connection

[flintcam]

I am trying to piece together a 70s Mercruiser 140 and got an unused Carter low pressure mechanical fuel pump at a garage sale. It has a marked inlet and outlet plus another port below the marked outlet. I can't find any information on this any where but am assuming it's for a water separator. If that is the case and I don't need a separator should I just plug it off, connect it to the carburetor line or run it back into the fuel line. Any help would be appreciated.

 

[Bt Doctur]

Re: Carter fuel pump connection

you have a inlet, outlet, and the "teltale" hose to the carb.the diaphram needs to breathe, thats what the hole is for in a auto application. Being in a boat you dont want gas from a ruptured diaphram dumping fuel in the bilge so a fitting and hose is used to pipe it into the carb. This prevents you from earning the "Darwin Award"

 

[fishrdan]

Re: Carter fuel pump connection

The bottom port (angled downward) is for the sight tube, piece of clear tubing that runs up to the carb. The sight tube is a new (since the 70's) safety feature to direct fuel to the carb, in the event the pump diaphragm ruptures. Better down the carb and making the engine run like carp, than in the bilge and blowing up the boat. Engines built with it have the tube plumbed into the top of the carb, on my 72 Mercruiser I plumbed it in with the crank case vent fitting at the bottom of the carb.

 

[fishrdan]

Re: Carter fuel pump connection

I like BT's Darwin Award response better than mine...

 

[flintcam]

Re: Carter fuel pump connection

Thank you both for the replies. I certainly don't need another Darwin award and will get it hooked up the way it should be. Thanks again.