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uneven carb butterflys - need guru advice

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kmarts

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So i had mentioned in another thread that my pto carb was slightly more open than my mag carb with no linkage arm attached...

basically ripping everything apart today to troubleshoot my problems and i snapped a pic of each carb in what should be it's fully closed position. Both carbs are bolted to a spare rotary valve cover i have, the linkage arm is not attached.

You can see from the pics the PTO carb has a sliver of light which isn't visible on the MAG carb.

first question is, since this looks like a minor difference would this affect performance anyway?

and if it will , can i lengthen the adjustment rod on the PTO side to hold the mag side slightly more open to try and even them out?

As far as i can tell the throttle butterfly isn't bent. I'm not sure how something like this happens but should i be looking at rebuilding the throttle shaft?
 

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Those are the choke butterflies. Not a big deal with what you have posted. Now... if one was open, and one was sitting at a 45 degree angle... that would be an issue.
 
Those are the choke butterflies. Not a big deal with what you have posted. Now... if one was open, and one was sitting at a 45 degree angle... that would be an issue.

I was referring to the throttle butterfly's... Best way to show it was with a light behind the carb so you can see the difference. From the other side you can't really see it.

I'm troubleshooting some running issues and I'm wondering if that's enough to have the carbs un-synced and run like crap on the low end.
 
The mechanical idle adjustment is on the mag carb. If the linkage is properly adjusted then it will hold the pto carb slightly open when it's connected once the carbs are bolted to the manifold.
 
The mechanical idle adjustment is on the mag carb. If the linkage is properly adjusted then it will hold the pto carb slightly open when it's connected once the carbs are bolted to the manifold.

In the picture there is no linkage arm attached. The PTO carb is slightly more open all on its own. With the linkage arm attached and idle screw adjusted it's even more visible.

Why would the PTO carb be more open if the linkage rod is adjusted properly?
 
OK gotcha I had that backwards then. Either the engine ingested something that bent it or someone before you removed the butterfly before. You can tell by the two small bolts. If they have been replaced make sure they peened the thread end so they can't come out.

I wouldn't worry about it unless I couldn't get the idle to come down properly. If it is affecting the idle then I'd feel free to "adjust" it a little.
 
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