My girlfriend has a lawnmower business and her 2 year old Encore Prowler runs great for 2 to 3 hours. It then cuts out continuously until it cools off. She has had it back to the dealer (SMITHCO EQUIPMENT PATASKALA, OHIO) 3 times today alone. This has been going on for 2 weeks now. The dealer has drained the fuel tanks, lines etc and replaced filter to no avail. fuel pump etc.. Any suggestions? She also has a 10 year old encore that has basically the same problem and has been doing this for over a year.