Tyla's right. There is no locking mechanism on 81-82 seats. Both are the same pan/hinge arrangement. Try pulling the side covers off, then (CAREFULLY) pry back the seat cushions to see down to the hinge. Use the other seat that works to get an idea of the range of movement of the hinge. Got to be something small wedged in there. Could even be a missing acorn nut that holds on the side covers. Good luck.