I have a 10 year old sv720-0010 in a club cadet. A few weeks ago it started running rough under load like going up hill. The speed would go up and down and then stop. I have replaced all the fuel lines, the fuel filter and pump also the air filter. I have also checked out the carb: checked to see that the jets were clear and the float and valve were working ok. All is fine. It worked fine on a flat lawn for about 45 min. and then started the up and down thing again. then it stared working ok then up and down till it died.
