My 35 Fountain just recently has developed this annoying habit. After about 5 to 10 minutes of running the alarms start to chirp, first stbd, then port, and continue to a full scale scream. Gauges all read normally. the resevoirs also are adequately filled, too. What else sets off these alarms?

Temp sensor, water pressure sensor, a bad sensor many many things...go get the motors scanned that will narrow it down for you....good luck


Undertaker

Are you utilizing complete smartcraft technology with vessel view, as well as ET & ESC's?

What motors do you have? The 454's and 502's only alarmed for temp, oil pressure, gear oil.

Disconnect your drive reservoir connectors to see if it goes away. Full reservoir means nothing when that sensro goes bad, or the contacts are dirty.

A little more detail would help. Is the alarm a 2 beep per minute alarm that goes full alarm around 40-4500 rpm? Or is it constant chirping? Does it go into guardian i.e. won't let you gain full rpm? When full alrm does it go away after the throttles retard to 1100k rpm or less?

Some of the early MEFI3 systems had a few additional alarms. For example they will set an alarm for any trouble code. Take a look at the Mercruiser Service Bulletin (link below), and check for trouble codes.

Dave

http://www.boatfix.com/merc/Bullet/99/99_03.pdf

Sorry, i was thinking 496, didn't catch the year of your boat.

the engines are HP500's with carbs.
I will try the disconnect at the resevoirs tonight.
The alarms are chips that start intermittently, then progress to a constant alarm that sounds like a European Police siren

Obviously no smartcraft on your vessel, good luck.

Chech the water crossover where the water temp sensors are make sure all nuts and bolts around there are tight .....the bolts are what give it ground....if loose tighten them up and see what happens.......it may be cool on water temp but the ground may be tripping the sensors making them go off