I own a 25 hp. 4 stroke BIGFOOT, about 4 years old with very low hours. The problem is that it drops down into slow mode as soon as it warms up. The impeller is new. The thermostat is working. The 'tell tale' is working but hot to the touch. The temp is about 170. The oil level was low at one point, but never below the 'add' line. <br />The problem began gradually after a period of non use (the fuel had been changed and the carburator was cleaned). At first moving the throttle up and down would clear the problem. Then we discovered that if you turned the motor off, it would run well on restart.
