fuel pump quick help

[dgopetactical]

mercruiser 5.7 alpha 1 1988

on my mechanical fuel pump there is a clear rubber tube comming off a *** in the rear of the pump. mine got cut by the engine pulley and I have no clue what it is or where it goes. the other end was just laying in the belige. where ever it goes the end looked like it was not connected for many years. I am having trouble understanding this in the merc manual its very very vauge and my eyes are starting to glaze over. All the other tubes connected to the pump are rigid this is the only rubber one.
thank you,
Dgope

 

[Haut Medoc]

Re: fuel pump quick help

It connects to the carb.....
It's purpose is to route fuel to the carb when the pump's diaphragm goes bad instead of dumping it into the bilge & creating a fire hazerd.....
The excess fuel will make the engine run poorly & force an investigation as to the cause.......
If you ever see fuel in that line, time for a new pump.....​

 

[dgopetactical]

Re: fuel pump quick help

thanks for the help. I will look harder at the carb and try to find where it is suppose to go. I dont think any fuel comes out that tube I will check that too.
many thanks,
dgope

 

[jfl1959]

Re: fuel pump quick help

HM is right (of course)

When looking at the carb, remember that some rebuilt carbs used the auto body from core that were returned (not good, just reality) if thats the case some carbs might not have a place for the tube to connect to. Look for a picture of a marine carb and you should see the stem where the tube connects.

good luck