Hi Just bought my 312 this spring when we moved into a new home with two acres of land. Love the wheel horse, but I am not even sure if I have to change a oil filter and for that matter where the filter or oil plug would be - any guidance would be appreciated. Put a little marvel mystery oil in the gas, and just started it up for a few, but want to change the oil for the spring. Any guidance on where to start would be greatly appreciated.