I have a 94 model 60 HP Evinrude. Had to replace the impellar. After replaceing the impellar, I started it up and all seemed fine with water flow but I noticed water building up in the upper housing below the powerhead. That does not seem right to me. Does it do this until the thermostat opens? Never saw any water coming out of the exhaust. Don't know if I have a problem or not because I was afraid to put it in the water. It just does not seem right to me that water would build up in the upper housing like that.