I have a 1987 70hp. Mercury outboard with oil injection. When i turn the key on I have a constant beeeeeeeeeeep alarm. When I start the engine it continues and will not stop. I just replaced the water pump and put in new thermostat. It was doing it before I did the replacement and after. I'm getting a good steady stream out of the peer and the water is cool coming out of the exhaust and the pee hole. Any suggestions would be very appreciated.