I have a 1985 90 hp on my skeeter. Today I finally got to go out for some fishin since I got the boat. My problem is that when I get up to around 4500 to 5000 rpms and run for a few minutes I get an alarm going off. I can put it in neutral and idle for a minute and the alarm goes off. If I stay under 4000 rpms the alarm never goes off. I kept checking to see if the motor was peeing and it was shooting a really good stream. Can anyone give me any suggestions as what to check. Thanks