Marine 350 with gas in oil

[bubbletop61]

Just discovered that when running last fall, the 350 in our ski boat was getting gas in the oil pan. Either that, or it drained out of the QJet after the boat was put away in the fall. I am sure that gas could drain into the pan through an open valve and past the rings, if the float sunk, or the needle got stuck open. But is it possible for the gas to get into the pan from the mechanical fuel pump, if it breaks a diaphragm or a seal somewhere?

Any thoughts on this would be appreciated.
Cheers
Gar

 

[Fran Preve]

Yes it is possible buy a leaking diaphram in the fuel pump, I had it happen to a Mercruiser with a 351 Ford Windsor in my 30' cruiser. New fuel pump (expensive!) solved problem. marine engines SHOULD have marine fuel pumps (if you replace).

 

[bubbletop61]

Fran;
I need this boat to be running by the weekend, and here in Montreal it is tough to find marine components. What is the difference between the marine and the automotive pump? Is it the hole for fuel drain in case of a ruptured diaphragm?

The other problem with this set-up is that the previous owner was having vapor lock problems when trying to restart when engine was warmed up. To correct this problem he installed an electric pump between the tank and the mechanical pump.
I am now thinking that this was creating too much pressure for the needle in the Q Jet to withstand, and that when the engine was off, but the key left on by accident, the electric pump may have been flooding the carb, and the fuel may have leaked down into the pan...????? If the diaphragm in the mechanical fuel pump was not ruptured then I'm guessing this could not happen. Ideas?

Thanks
Gar

 

[Fran Preve]

Gar: I replied to this post, did you get it?. :?

 

[bubbletop61]

Fran;
Yes I got it. My reply just gave a bit more info on the problem I was having and
asked what is the difference between the Marine and Automotive fuel pumps if you know. ( And I'm guessing that you do know)

BTW were the Marine versions built at Tonawanda too?

Thanks
Gar

 

[models916]

marine pump

big block fuel pump in my old jet drive had an external vent fitting to the outside of the hull. Pretty sure it was and AC.

 

[Fran Preve]

We built marines when we were building V-8's, up to about 1979. My fuel pumps didn't have a "vent", I'm pretty sure there was a second diaphram that prevented any vapors leaving the pump.

 

[bubbletop61]

I have the second diaphragm on my Marine Pump. Also no vent hole. I guess this was to avoid any fuel getting pumped into the bilge. You were right about the cost of the marine pumps...ouch $120 Canadian, vs $30 for an automotive pump...
Thanks
Gar