New Carb - Chain rotating now on idle

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muddtree

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Installed a new carburetor. It has a couple screws on the side. Haven't messed with it. When then chainsaw starts, I pop the throttle to get out of high idle, then adjust chainbreak. The chain is spinning on low idle.
 
If the idle screw doesn't drop idle enough it could possibly also running a little lean which will increase idle speed or also an intake air leak. Just getting the idle down doesn't mean it is tuned properly especially with aftermarket carbs.
 
If the idle screw doesn't drop idle enough it could possibly also running a little lean which will increase idle speed or also an intake air leak. Just getting the idle down doesn't mean it is tuned properly especially with aftermarket carbs.
If the chain is spinning at idle, and you cannot figure out how to idle it down, or it won't. Use the chain brake.

Turn idle screw left and right and find the highest RPM. Then go CCW maybe a 1/4 turn richer and turn your idle speed screw up to get the RPM where it moves your chain or not.
 
Turn idle out until chain stops spinning.

Turn low screw in until it stumbles, then out until it races. Set low 1/2 in between. May have to adjust idle again and repeat above, sometimes twice.

If saw stumbles when you give it gas off idle it's lean on low, turn low out (richer) a bit.
 
Well, there is a point on old saws where the springs are weak or broken, and the only choice is to replace them if you want the chain to completely stop.

Same with weed eaters .
Seeing as it's most likely a zenoah clone, it wouldn't be surprising if the clutch spring was worn out long before it became old. Seen plenty of threads recently asking the same questions, and turb out to be a bad/broken clutch spring.
 

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