We have a 1985 8 hp Evinrude that acts up once in awhile. I would be going around 15 mph when the normal engine sound changes to a wah-wah-wah type sound and the speed drops to around 3-5 mph while the engine is still wound up. If I run it at a low power setting for 3-5 minutes, it goes back to normal. The outside temp was around 80 degrees. There is no thermostat in the motor and it has new plugs which did help. I emptied out the gas can and put new gas/oil in it. The water pump it putting out water OK. <br />I felt the head once and it wasn't hot. It has done this 5-6 times.<br /><br />Does anyone have any ideas? Thanks.<br /><br />Bob.