I have a 1998 gamefisher 15hp which I believe is the same motor as a force 15hp 94-97.The problem I`m having is where is the water suppose to come from indicating the pump is working.I installed a new impellor but still see no water after about 1 min of running.This motor also has a thermostat which sits on the backside of engine just under cowl cover.The tstat is held in place by a plastic cover and gasket.Could someone explain to me how this setup is supposed to work.I haven`t replaced tstat yet and it is corroded.The motor also has two small rectangular slots under the tstat housing.Could this be the tell tale holes?Help!