generac QP75G linkage adjustment

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Joined: Thu Mar 05, 2020 4:16 pm

I have been trying to trace down a surging problem on a Generac QP75g with 7200 hours on it. Just tuned, new carb, valve adjustment, fuel filter, etc., it is used 4 days a week with oil changes at every 100 hours. It runs great until I turn the water heater on (6 gallon 240volt tank , just flushed and new element installed), then the extreme surging begins. I have played with the linkage adjustment and it has gotten much better, but I dont know where to connect my multimeter to make sure I am adjusting it for the correct voltage. It is installed in my wifes mobile animal grooming truck. Any help would be appreciated. Thank you
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Location: Clawson, MI

There is an entire procedure for adjusting the governor listed in the diagnostic manual which can be found here: ... tic-manual
It covers the QP55, QP65, and QP75 in both gas and LP configurations. Has all the wiring diagrams, adjustment procedures, settings, etc.

Most times surging is caused by excess slack somewhere in the linkage or springs. 7200 hours is A LOT of run time :shocked:
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