A locking mechanism includes a pin configured to movably couple to a first element of an agricultural header, wherein the first element includes one of an arm and a frame. The locking mechanism also includes a mount configured to couple to a second element of the agricultural header, wherein the second element includes the other of the arm and the frame. The pin is disposed within an opening of the mount, the opening has a first portion configured to receive the pin while the pin is in a first position and to block relative movement between the pin and the mount to block rotation of the arm, and the opening has a second portion configured to receive the pin while the pin is in a second position and to enable relative movement between the pin and the mount to enable rotation of the arm.