I have a Hayward Super II pool pump, A.O. Smith motor, 2 hp, 2 speed model SP1615Z2MC. It runs fine on low speed, then when going to hi speed it kicks off. I have replaced top capacitor, not the problem. Do you think its start capacitor or thermal switch? Do you sell either for this model? With its age, should I just replace the motor? Thanks in advance for any help.