HAve a toro 6.5hp and it will blow out white smoke when it's on an angle.it's burning oil what could cause that. Im pretty sure oil got in to the exhaust.
When you say incline I'm assuming more than 15 degrees. You have to be careful which direction you are going. If you are mowing with the carb and cylinder are on the down side of the incline and long streches, oil is being stucked in. Always try to mow so that the carb on the upside on the incline. On hills or large inclines always try to mow across, not up and down.
