I have a Exmark Lazer Z XS, with a 35 Briggs Vanguard. The motor has 511 hrs. bought in March 07. I told my dealer that the motor is starting to use oil and i can smell the oil. He told me that the motor is sucking air and it needs new rings. But he also said Briggs will not warranty the repair work. I also have a 31 Briggs Vanguard that has 1100 hrs. without any problem at all. Why don't Briggs fix this motor. I use nothing but EXmark mowers. Can you tell me why they want fix this motor. The dealer tell me to use nothing but Briggs air filter.