I have a 2002 Walker MT with 20 hp Kohler. I bought it used, so I don't know all history. One of the belts on the ground drive system is slipping. Once the transmission is up to speed it goes very fast. I mention this because I had the engine rebuilt this winter and the pulley on the engine broke during removal. I bought another pulley kit. When I purchased the pulley, a second pulley came with the kit and a note saying that the pulley should be used instead of a speed-up kit pulley. Is my belt slipping because because I didn't use the slower pulley? The note in the box said that damage could occur if the speedup pulley is used, but it really goes fast. .