I have recently aquired a Mariner 70hp Outboard. Serial # 5702226 Can someone please tell me the year model of this motor. Also it is Puting Exhaust out the P hole hose. I have bought a new water pump and put it in. Ive heard about thermostats in these motors but can not find were mine would be Located. I do believe this motor to be a 1980 model do to pervious owner.? Idk whats wrong with this so any Advice would be Greatly Apperciated.