What's involved in changing 74 single diaphragm fuel pump to new model w/sight glass?

[cheburashka]

I'm getting a strong fuel smell from the engine compartment of my '74 140 Mercruiser, but I can't find the actual leak. It has an automotive-style fuel pump with no return line to the carb for leaks. I've checked the fuel pump and the diaphragm and everything looks good, but I'm thinking it might be time for a new fuel pump. Can I put the newer model with the sight glass onto this engine with the existing old-school Rochester carb, or do I need a newer carb with different fittings on it?

Thanks

 

[bruceb58]

Re: What's involved in changing 74 single diaphragm fuel pump to new model w/sight gl

Fuel pumps don't have sight glasses anymore.

 

[Limited-Time]

Re: What's involved in changing 74 single diaphragm fuel pump to new model w/sight gl

If the fuel pump checks out OK I'd be chasing down the "strong fuel smell".

 

[Bt Doctur]

Re: What's involved in changing 74 single diaphragm fuel pump to new model w/sight gl

find the leak first, might just be the gas tank.And get the proper marine pump with a vent line to the carb or you risk getting blown up.

 

[ziggy]

Re: What's involved in changing 74 single diaphragm fuel pump to new model w/sight gl

And get the proper marine pump with a vent line to the carb

i'm gonna go out on a limb and say he does have the right fuel pump. mercruiser sm's don't talk about the return line untill #3. 1978 i think. if ya have the carter fuel pump. the diaphram can be serviced. check out yer s/m on fuel pumps. all that said. i think if i had a fuel pump leak. i'd R&R it to the new version bd is talking about. the one with the vent line. if ya have a 2gc carb. look right under the fa on the starboard side of the carb. ya may see a brass plug there.... a pipe fitting can go there instead and the vent from the new style fuel pump routed to it....

like lt said too. no point in R&Ring a fuel pump if that ain't where the leak is... find the leak.... with a leak somewhere, and ya can smell fuel. you are a bomb waiting for ign..........