Well, I'm not much help judging by this machine. Just checked out the .pdf for the 7313 model and appears the v-pulley assembly is upside down. Seems the large end of the pulley, which is shown as the drive belt section, should be at the top, where my machine it is on the bottom driving the cutter deck. Whoever replaced the motor seems to have put it on the wrong way. It still works..... hahahaha.....
Haven't seen a brake pad yet, so will go have another look under the mower. Also, according to the IPL, there is only one spring, yet this machine has two.
Maybe someone could shed some more light on these anomalies.