I suggest you get rid of it. I have had one for just over a year and found out why the drive so badly. The bearing on the right rear(one with the adjust handle) is seizing. What happens next is the drive shaft is going to break. Parts alone will cost you about 120.00 online. Pretty sad for a push mower that cost over 400.00.
drive asm averages 80.00/ kit.sel asm averages 40.00