Scrapheap Challenge (1998) : 3x7

There's an acre of wheat to cut and collect. This semifinal Junkyard challenge sends the competitors down to the farm to see who can build the best mower. One team turns a taxicab into a take-no-prisoners lawnmower, while their opponents turn a pickup truck into a harvester. Amid lots of smoke and chugging, both teams' machines "buy the farm." The winning machine is an impromptu scythe made out of a foot of metal.