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       #Post#: 68066--------------------------------------------------
       Walbro HD 34A accelerator pump
       By: kr5258 Date: January 11, 2016, 7:47 pm
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       Having a tuning problem with a MS361. Carb tunes normally on the
       low side but I can't get enough fuel into it on the high side.
       The saw runs up close to 15k no matter how many turns out on the
       H screw. Carb swapped from another MS361 and saw tunes normally.
       The problem carb has been kitted and thoroughly gone thru. I
       suspect the accelerator pump circuit is pulling air in past the
       pump piston. Pump piston shows scoring just as I have seen on
       the problematic MS200t ZAMA C1Q-S126 accelerator pump.
       Can anyone verify this theory before I plug the pump bore to
       test (and give myself another project trying to get the plug
       out)?
       #Post#: 68068--------------------------------------------------
       Re: Walbro HD 34A accelerator pump
       By: jmester Date: January 11, 2016, 9:17 pm
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       From what I understand if the pump piston is scored it will not
       hold a vacuum behind the pump piston to draw fuel from the
       metering side of the carb. I am not sure if it feeds fuel the
       hole time the throttle is open or just when you first depress
       the throttle.
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