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Merc 1985 75 hp 4cyl Throttle butterfly sync problem

C

cowboyup

New member
Hello All,

Make a long story short. I had the carbs rebuilt from 2 different guys who supposed to know how to do it..Didn't.. Carbs kept on leaking and would not idle adjust. So I just went ahead and purchased 2 New ( Rebuilt ) from here. I am having trouble getting the butterflys to sync. The old set when the butterflys were closed both were and WOT they both were vetical inline. As you can see from the photos With the throttle all the way closed the bottom carb cylinders 3 and 4 it is still halfway open. Top is fully closed. At WOT the top cylinders 1 and 2 the 3/4 open...I hope some can give me a idea how to set the so they work in sync. Sorry about the photos best I could do. I would really like to get these set up so I can do a link and syn. I asumme it has something to do with the coupling assembly mabey? Throttle cable is disconnected I am moving the arm by hand. At WOT Bottom card is set perfect vertical against the carb body stop.

1st photo Bottom carb throttle closed (Butterfly 3/4 open)

2nd Photo top carb throttle closed (so is the butterfly)

3rd photo top carb Thottle WOT (Butterfly 3/4 open)

Than You Cowboyup
Merc 1985
75 HP 4 cyl 2 Stroke
Ser# 0a116960

Bottom Carb Throttle closed.jpgThrottle closed.JPGTop Carb WOT..jpg
 
There's a black plastic piece that connects the carbs. Yours is either broken or out of adjustment. The screw at the bottom of this piece is where you adjust it.

Jeff
 
Thank You fast Jeff I got to tinker with it and loosened the screw bottom one and readjusted it. Got the almost perfect. had to work over the weekend and rain is coming today, But I see how it sets up now Thank you so Much!

Cowboyup
 
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