location of the idle mixture screw...

[sqb]

I recently purchased a '79 80 hp mercury outboard motor for my boat that starts and idle fine, but when put in gear it stalls. I have done some search on this forums and came to the conclusion that I need to adjust the idle mixture screw. The problem is I do not know which screw of the two (one on the left and one on the right)is the idle mixture screw. The motor did not come with a repair or user's manual. Could some one on the forum tell me which of the two screw is the idle mixture adjustment screw. Thanks in advance...

 

[Chris1956]

Re: location of the idle mixture screw...

I would think you have two WMK-11 carbs on that motor. These are sidebowl, single barrel carbs with only one screw showing. If so the mixture screw is at about the two o'clock position next to the barrel, while looking at the open end of the barrel.<br /><br />The only other screw I can think of is the one that holds the black choke shutter. That is at the six o'clock position. I also recommend you get a manual, they are decisive with these old motors.