? on a Mercury 60 hp

My warning horn on my Merc 60 hp goes off when I pull the throttle clear back and run as slow as she’ll go. The horn kicks on after about 5 minutes of running like that.

Owners manual says that means its overheating, but it sure doesn’t seem like it. Do I need to replace the impeller, or water pump maybe? I know neither has been replaced in the last six years at least. Or maybe a faulty warning horn?

The motor’s a 1993. Anyone have any experience with that or have any ideas? I’m not a motorhead at all.

Is there water still coming out of the pee hole?

It sounds like the water pump is going. At low RPM’s its harder for the impeller to get water to the motor.

Ron

After 6 years, you bet I’d replace it.
Should be done every 2 to 3 years for the peace of mind.

I have a 1992 Merc 90 horse that does the same thing. I replaced the impeller and that didn’t fix it. After some more checking, I found that warning horn module was bad. $100.00 later it runs great with no alarm.

Is it oil injected? Low oil?

It’s full of oil, and still pees water strong as ever.

Definitely replace the water pump/impeller. It’s overdue. If you still get the horn, it could be your thermostat that is stuck or a bad sensor.

-J.