I bought this used last fall and have put about 10hrs on it so far. I was mowing a lawn yesterday and it all of a sudden quit driving forward or backwards. All the belts are moving when in gear and in neutral. When I push forward all pulleys stop and it doesn't move. Do I need to adjust the clutch or have it replace? I have no experience with this machine, and am at a loss. When thinking back it did seem that it was moving slower than average for a while before this happened. Any help would be apprieciated.