MY BUTON MOWER WITH A HONDA GV400 DOES NOT RUN SMOOTHLY -- IT REVES UP AND DOWN - IT HAS RUN FINE FOR ABOUT 15 YEARS BUT NOW IT JUST KEEPS GOING UP AND DOWN AND SOMETIMES I HAVE TO RUN IT WITH A PARTIAL CHOKE TO KEEP IT GOING ?
ANY HELP ON HOW TO FIX IT WOULD BE APPRECIATED .
BILL NOLAN...