Howdy, I have a 15hp Kawasaki engine on a exmark walkbehind.. I didnt check the engine oil for a few weeks and I have just checked it recently.... it was just about empty... so I added some oil and asked my dealer for some advice he says change the oil every other week and just pray the engine dont blow up So anyway do you think changing the oil will help the engine go back to normal!!?!? Need some opinions. Thanks!!