Mercruiser 454, 7.4L fuel pump lubrication

I had a failed fuel pump.  Symptoms were simply stalling out on the water and then losing power and needing to pump the carburetor to get going.

Replacing the fuel pump is straight forward.  Remove the fuel lines and the two bolts holding the pump to the seawater pump bracket.  Inside the little cavity is a eccentric wheel that moved the fuel pump lever back and forth — thus pumping fuel.

In my case, this cavity was filled with gasoline — the pump had failed and filled the cavity.  I used paper towels to soak up the gasoline and clean out the cavity.  Before I put the pump on I wondered about the metal-to-metal contact of the eccentric wheel and the pump lever.  When studying both the  Clymer or Mercruiser manual about replacing the fuel pump, I could find nothing about lubrication.  This worried me.  I read posts on several boards and could find nothing definative there.

Finally, after searching through the Mercruiser manuals, on drawing 71121, in the section about rebuilding the seawater pump, there is an indication about lubrication of the fuel pump.  ( Mercruiser service manual via boatfix.com )  FuielPumpLubrication

Of course, my engine was a little different…  It only has one screw but this is fine.  I can remove the screw and pump in lubricant.

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But what lubricant?  From #6…..Gear lube!!!!

FuelPumpLubrication2

 

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