Fuel leaking from carb jet.

Hammer53

Recruit
Joined
May 23, 2015
Messages
5
I have a 1985 Mercury 50 hp outboard. It has dual wma3 carbs. We had a severe leak in the lower carb at the end of last year. Fuel was coming up through the jet and out the front of the carb. I decided it was probably a good idea to rebuild the carb and fuel pump. However after doing this we are still getting the same leak. It does not pour out but is a constant drip when the fuel line is connected.

In my trouble shooting I left the bowl and float off and manually held the needle in place. However I still get fuel leaking. My first thought is fuel getting between one of the gaskets on the fuel pump and down the hole to the right of where the needle sits. I did not put any sort of seal the or anything on the fuel pump gaskets before I put them on. Should I have put something on the gaskets this?
 

enginepower

Petty Officer 1st Class
Joined
Jul 5, 2014
Messages
260
You either have bad needle/seat or your float arm is bent causing too high of fuel level
 

Hammer53

Recruit
Joined
May 23, 2015
Messages
5
I did replace the needle when it was rebuilt and where the needle seats is not removable. The float level is correct. Even when I physically held the needle in place fuel still weeded past the needle.
 

enginepower

Petty Officer 1st Class
Joined
Jul 5, 2014
Messages
260
Ok so you have a seat problem unless you obtained a bad needle (should be able to see a good even taper on needle tip). Not familiar with all the different carbs out there and if seats are pressed in or not but sometimes you can fix this using a knurling tool i think it's called. It's what is used to remove the inside roll over of tubing after you cut it. Don't get carried away with it, a light use should do the trick. Make sure to recheck float level afterwards.
 
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