Mechanical Fuel Pump

[Dougc87]

I just acquired a boat that has a 3.0 Mercruiser. Not sure of age of the motor yet but I would say between 1974 and 1980's. Anyways while it is running there is fuel spraying out of this hole. (circled in red) It is not a steady stream it sprays a second then stops for a second. Ok now the questions
Is this hole normal?
If not can I just fill it with like JB weld or something?
If it is normal what does it mean since fuel is flying out of there?



Thanks
Doug

 

[EddiePetty]

Re: Mechanical Fuel Pump

Fuel from that hole tells you your fuel pump diaphram is ruptured....and you have an automotive pump on that engine.
Replace with a MARINE fuel pump and connect the bleed tube to the carb.

The auto pump is grounds for a CG citation. The leaking fuel is the preamble of a boat fire.

 

[Bondo]

Re: Mechanical Fuel Pump

Ayuh,... Welcome Aboard,.... That tube hanging there is supposed to be hooked to a fitting in that hole circled in red...

Somebody put an automotive pump on there,... As noted, that's a Big No-No...

Btw,... That 1 is Junk, 'n needs replacein'...

 

[180shabah]

Re: Mechanical Fuel Pump

As stated - new pump required, and it MUST be marine...

 

[Dougc87]

Re: Mechanical Fuel Pump

Wow, I do not know where to start. First Thanks for the quick response! Second I wonder what else this guy installed on this motor that shouldn't be installed. Again thanks guys for letting me know about this I am going to go get the right one tomorrow!!

Thanks,
Doug

 

[Dougc87]

Re: Mechanical Fuel Pump

Well I got my new fuel pump in but there is one slight problem where does this new line go?
Looking at a old manual from mercruiser is it possible that the factory installed it before CG regulations?

http://www.mercruiserparts.com/show_image.asp?ivar=images/CRUISER/37325/7.png

I am sure I am just over looking where the line might go, but I just can not find a spot.

 

[danyboy]

Re: Mechanical Fuel Pump

Well I got my new fuel pump in but there is one slight problem where does this new line go?
Looking at a old manual from mercruiser is it possible that the factory installed it before CG regulations?

http://www.mercruiserparts.com/show_image.asp?ivar=images/CRUISER/37325/7.png

I am sure I am just over looking where the line might go, but I just can not find a spot.

i belive it goes on the carb.

 

[howlnmad]

Re: Mechanical Fuel Pump

Should be a nipple at the top of the carb. This way when the pump goes bad, it pumps fuel down the throats and floods the motor instead of flooding the bilge and going KABOOM!! If your carb doesn't have that, it may well be automotive as well and needs to go also.

 

[Eric 3.7LX Alpha 1]

Re: Mechanical Fuel Pump

Well I got my new fuel pump in but there is one slight problem where does this new line go?
Looking at a old manual from mercruiser is it possible that the factory installed it before CG regulations?

http://www.mercruiserparts.com/show_image.asp?ivar=images/CRUISER/37325/7.png

I am sure I am just over looking where the line might go, but I just can not find a spot.

How bout some pictures of the engine and carburator. We like pictures!!

 

[fishrdan]

Re: Mechanical Fuel Pump

My old 73 Mercruiser didn't have a fuel pump vent tube fitting, vent tube and the carb didn't have a fitting for the vent tube either. I'm under the impression it was before the USCG regs for the vent tube, as you are thinking. When I replaced the old fuel pump with a new style, with vent tube fitting, I added a fitting to the flame arrestor to connect the vent tube, so the fuel would dump straight down the carb. Newer carbs have the fitting in the side of the carb.

I thought of putting a T into the carb's crank case vent fitting, so that might be an option.