Alarm on 2 stroke Johnson 85hp

Have a 79 Johnson 85 that alarm goes off. Indicator shows good water and the motor runs fine,have run it back 6 miles with alarm going off. Motor has done this several times but does not seem hot.Anybody got any idea what it may be? Thanks

http://old.charlestonfishing.com/forum/topic.asp?TOPIC_ID=147753

I had an alarm issue with my 90 2 stroke. It turned out to be the tach. I have attached the thread.

17 MAVERICK HPX-V