1989 Mercury 9.9 carb size vs. smaller engines

[gm280]

Blustream, that seems interesting that the exact same carb body is used for all those different HP engines. Because the carb body sets the venturi opening and the only difference is the jet size. Since the venturi allows only so much air flow, changing the jet size seems to only change the air/fuel ratio. Seems odd. JMHO

 

[ondarvr]

Blustream, that seems interesting that the exact same carb body is used for all those different HP engines. Because the carb body sets the venturi opening and the only difference is the jet size. Since the venturi allows only so much air flow, changing the jet size seems to only change the air/fuel ratio. Seems odd. JMHO

He was told there are 3 different carbs, or at least part numbers.

 

[flyingscott]

Look for a VM# on the carb. That is the important one you need usually on the mounting flange.

 

[Bluestream]

I checked the main jet today and its a .046. That means this carb is from an 8 HP; I was taken by a scum bag seller!!

I cant in good conscience sell this motor as is. I need to either find a 9.9 carb, part it out, or sell it as an 8hp

 

[hardwater fisherman]

I know how you feel. Less than 2 months ago I bought what I thought was a 25hp merc and it turned out to be a 20hp.