Do not use automotive belts. Install the exact belt intended for this mower. Check the stack pulley to see if there is wear on the pulley.

I bought the exact belts made by MTD. No wear on the pulley.

I don't understand what the problem is.

Are the brakes not working or is the clutch out of adjustment or both?

I'm at a loss, too. When I try to stop, I get this grinding noise and it jerks to a sudden stop. When I let out the clutch, it just grabs and does a wheel stand. This NEVER happened with the old belt. I decided on a new belt when the tractor stopped halfway through mowing the lawn. It was worn. It finally just shredded to bits. I checked the routing over and over. It's correct; inside all the belt posts like the diagram says. I took the pulley off and inspected it - it works fine. Only remote possibility is that someone at the store repackaged the belt in the wrong box. But it fits good. There must be some adjustment because it seems to engage the brakes BEFORE releasing the tension on the belt.

Here's a link that might help. Look down the page a little.

Here is a link that might be useful: link

That link is dead.