Carb orifices on 81 Johnson 70hp

[Sliver]

OK so I finally am rebuilding them and (kick me here) didn't notice that the intermediate and idle orifices had a different bore size. So it would seem logical that the intermediate (on the top behind the core plug) would have the larger bore. The manual doesn't say but this makes sense to me... Please correct me if I'm wrong. Also, do most of you dissassemble the butterflies from the body for cleaning when rebuilding or just soak the whole thing. Many thanks.

 

[tashasdaddy]

Re: Carb orifices on 81 Johnson 70hp

your top and bottom carbs are alike, the middle one is different,

http://forums.iboats.com/showthread.php?t=244013

you can look up diagrams here. http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

 

[Sliver]

Re: Carb orifices on 81 Johnson 70hp

I'm talking about the orifices on 1 carb. The intermediate is on the top and the idle goes in the side.

 

[Sliver]

Re: Carb orifices on 81 Johnson 70hp

Part #'s 27 and 35 on this page. The manual dosen't describe them better as far as bore size but they are different. I guess I'll have to pull one of the other carbs to find out.

http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

 

[awsome66nova]

Re: Carb orifices on 81 Johnson 70hp

OK, did you ever get your carbs rebuilt? Did you learn how to set the air screws? I have one I am working on and everything is not adjustable, all the jets go in tight, and the only screw thats adjustable is the one at the top center of each carb. I am trying to find the correct setting for the top, botton and center carb. Don't know if they are all the same or each has a different setting for that screw. Let me know will you. thanks.