Yamaha Carbs on a Merc 2.5

[XTB21]

Anyone have any info on how to set these up?

They are 34mm for a 225 Yamaha.

What can i do to make them fit a merc intake?

[XTB21]

ttt

[Rusrog]

and it does work very well. If I am not mistaken you have to turn the throttle shaft around and I know that you have to slot the mount holes in towards the center to fit the Merc manifold. Used to the reason for doing this was because of the superior idle characteristics of the Yamaha carbs but with the newer Merc carbs running so well it is not as commonly done.

Hope this helps,

Russ Rogers
Ft Worth TX

[XTB21]

Thanks for the info rusrog!

We've tried numerous merc carbs and they all idle like crap and spit and spudder when going off idle so we were looking into some info on the yamaha carbs as a possible replacement

[Wile E. Coyote]

Bruce Ditto has apparently got that down to a science, he offered rich a set to test at the Eustis race and I'm pretty sure sammys motor has a set.

You have a PM

[fasteddie]

All the info you guys can provide will be appreciated by many.
I am trying to rectify a problem with mine as we speak.My245 carb merc goes like hell up to 8000RPM and then quits pulling.
I have been told by a few people that it is due to the float bowls probably being sucked dry (WHM carbs).I have been told that the needle and seats need to be increased in size to solve this.I have searched and searched for parts to change this, but am not having much luck. The closest thing I have found are from a rochester Qjet, but they are quite a bit to tall and I can't get the float settings correct.

If this problem can be solved as easily as changing to the yammi carb, somebody hook me up with the guy who can get me some.

Ed

[XTB21]

Hey thanks for the info billy!


i think dorsey was looking for his number but couldnt find it!

Fasteddie: if your turning 8 grand with that 245 i would say your doing damn good mine will only turn about 7800 with a 24 chopper and 68 mains

[Ray Neudecker]

Bob Kottman has this down to an art . His number is 636-338-4080. Offers on a turn key basis. Bolt on and go.

[XTB21]

Thanks for the info Ray,

we will try to get with Bruce i was told that he learned from Bob plus he's closer