20 Most Recent McCulloch Fg5700ak 5,700 Watt Portable Generator Like Questions & Answers

the carb needs to be cleaned I think the internal jets are plugged

You have a faulty inverter board on the unit. I would warranty the generator in this case, or have the manufacturer send you out a replacement board to swap yourself.

.010" inlet hot and .012" exhaust hot

https://www.manualslib.com/products/Mcculloch-Fg6000mk-278219.html

Ebay has the carb for under fifteen bucks. Want to add a note on calibration or recalibrating when replacing the carburetor. McCulloch FG6000 or FG5700, Wen, and many more use the same wenling jennfeng (wenling jenn feng) engine. On the FG6000, FG5700, and others, you'll see both an idle speed screw and an idle mixture needle valve on the carb. On top of the engine, you'll see the governor sensitivity spring tensioner screw top center of engine. First, loosen the governor spring tensioner screw until its loose with spring totally collapsed. With no load, adjust carb idle to 60hz-62hz using a multimeter. Now adjust the carburetor needle valve to the highest smoothest idle speed (highest possible hertz on the multimeter). Then readjust carb idles speed screw back to 60-62hz max, nothing higher. Finally, adjust the governor spring tensioner screw to calibrate governor sensitivity; loosen for less governing, tighten for more governing, and too tight will take away and defeat idle speed screw on carb. It's a delicate balance, takes some work, but when finished the generator should always maintain 60-62hz under any load condition.

Multiple choice depending on which power head ( alternator). Try generatorguru. https://www.generatorguru.com/capacitor-16234087/