question about 1980 mercury carb

[charliesal7]

Hi, i am looking for a mercury WM-11 carb for a 1980 70hp. I have seen for sale WM-11-1 and WM-11-3. Does anybody know the difference or if these would work for me?

 

[racerone]

What is wrong with the carburetor you have ?---Most carburetors are repairable.----What is your motor doing / not doing ?

 

[charliesal7]

The motor seems to idle fine, but it will stall out when put in gear while in the water. With earmuffs on it will shift into gear just fine. I thought of rebuilding the carbs, but the kits are $90 a piece for this motor (2 carburetors). I saw on ebay WM-11-1 carbs for sale for $20 a piece and i am wondering if it would be better to just buy those.

 

[flyingscott]

You will probably have to rebuild those carbs to. What is the model # mercury usually makes 2 kits for their carbs one complete overhaul kit with springs and one kit with just the gaskets.

 

[racerone]

Stalling when put in gear is CLASSIC of low speed fuel mixture too lean.-----Do this on the water.---Open each low speed needle 1/4 turn at a time and shift to forward and take off again.---Report your results !

 

[DavidMoore]

Could be talking out of turn here but did you set the idle speed on the muffs? If so just bumping up the idle speed might solve the problem.

​Remember idle speed is set on the water with the boat in gear (this is important), so set the idle 100 rpm faster than rated when on the muffs and see if you can pull away. Then set the idle speed properly when on the water.

The idle speed is set by the ignition timing, for a good set-up you should follow the synchronisation procedures spelled out in the manual. You can view the manual and print the procedures for free at boatinfo.no if you don't have one.

Could save you buying un-needed parts.

As for the carbs I believe WM 11-1 will be the top carb, WM 11-3 will be the bottom one. The difference probably in the linkage and the fuel connectors.

 

[charliesal7]

Stalling when put in gear is CLASSIC of low speed fuel mixture too lean.-----Do this on the water.---Open each low speed needle 1/4 turn at a time and shift to forward and take off again.---Report your results !

That fixed it!!!! She is running perfect now. Thanks so much!!!

 

[racerone]

Give yourself a pat on the back for accepting that it is very simple sometimes