1981 50 hp mercury fuel problems

[grantusw]

I have a 1981 50 hp 4 cylinder mercury and i am having an issue with the fuel getting to the motor. I changed all of the fuel lines, gaskets in carbs, primer, valve at the motor and gas tank and it still is runnig rough. It will lose a little power and if ou pump the primer it will boost the power back up. I have tried everything. thanks for any help you can offer.

[mercerfisherman]

I've got an 84 merc that had the same problem... changing the fuel pump might be your next step in troubleshooting the problem. It sounds like you've addressed the other issues that could affect it. Good luck. If you don't get any more advice... post your problem again... maybe more people will pitch in with some other good advice. Good luck.

[lil_jason17]

^^^

[mcgl403]

Did you ever get this fixed? I have the same problem with the same motor. I have change all fuel lines rebuilt the carbs, and recently installed a fuel pump in line before the primer bulb just to get me in the water. the fuel pump is out of an old Subaru wagon. It runs good but I would like to have it back to norm.

[TheRealSangster]

How ironic, I just bought a boat with a 1981 Mercury 50 hp 4 cyl that had the same issue from a guy named Grant. Hmm.....

The problem was...........................carb to motor gasket was on upside down, which blocked a fuel port that allowed fuel to flow to the fuel pump.


Runs like a top now.

[theoz60]

I have the same motor, same year, lot of the same problems.
Tried the same fixes. Mine would be running great full throttle
then spit, sputter, idle down & run at idle even though I was still at full throttle. Been trying to get it running good for two summers. 7 times my
"mechanic" said he had it fixed, 6 times I brought it back to him. Not 7!!
Any ideas...ted