Jumps out of gear - 1969 Firestone (MTD) riding lawn mower
Hello all, My riding lawn mower is jumping out of gear. It is a 2 direction one speed transmission. It jumps from both forward and reverse under heavy load. The input is a horizontal belt from below. The output is a vertical chain drive to the rear axle coming out the right side of the transmission when looking from the rear. I am going to take it apart soon and am trying to get a line on what kind of wear would cause this. What should I be looking for? Also, say I found a bad or worn part, where would I start my search for a replacement? As always thanks to those who will help.