Beeping Alarm on 120 Force

[kamboat64]

New issue today. Had the boat out for 4-5 hours. Running around some.
Trolling and fishing some. As I was starting to load the boat, I got three beeps, then three beeps, etc. Not sure what the alarm was but had my
trailer on the ramp so not the time to troubleshoot. Impeller is new
this year. Running 50:1 ratio. No VRO.

 

[Nordin]

The beeping sound from the buzzer is signal from the overheat sensor.
As you have changed the impeller I would suggest you to check the thermostat.
If it is stuck or do not open at right temperature the head will be hot enough to trigger the alarm.

A cheap infrared temerature gauge (gun) is a good tool to have in the tool box.
Just aim at the head and pull the switch and read the temperature.

BTW the overheat sensor is mounted in the power head and the hottest points is just around the plugs.

 

[jerryjerry05]

Year? model? serial# ?
The earlier models to 94 used Prestolite Ignition and usually only produced a solid BEEP.
The Mercury system shouldn't do anything different.
Unless you have a Sport Jet or PWC with oil injection.
So what we working on?

 

[kamboat64]

1998 Force 120 HP... Not sure of the serial number. I have to keep in storage as it won't fit in the garage
and our neighborhood association does not allow boats to be kept in driveways..... Will get this week when
I run by there.

 

[kamboat64]

Pulled the thermostat out and put in a pan of water. Didn't open at temp. Replaced and ran the motor.
All is good. Thanks for the help guys.