95 Force overheat horn

[bonzoso38]

So I just started doing my own maintenance on my 120 hp Mercury/ Force (1995) and I'm trying to find the overheat alarm/ horn. The Clymer manual tells me zippo about this. Anyone have a picture or can tell me where it is and what it looks like? Thanks.

 

[scottmm73]

You should have an orange wire running from the terminal board to a overtemp switch on the head. Grounding out the terminal should cause the alarm to activate.

https://www.youtube.com/watch?v=9Z-7igC1FF8

Goto 1:05 you will see a black wire running to the head just right of a label, that is the overtemp switch.

 

[Jiggz]

The overheat sensor or the horn itself? The sensor is as described by Scottmm73.

 

[bonzoso38]

Thanks fellas, just need to ground it to check if it's working..

 

[foodfisher]

Will probably sound like a buzzer under the dash.

 

[SteveinVA]

Is this the same for a 94 120?

 

[bonzoso38]

Hey, Anyone know where a convenient spot on the motor to ground this is. Seems like all the terminals to the sensor are hidden behind other stuff and would require some disassembly to get to them. I had to go to the horn itself behind the helm station to ground it. And by the way, why do they change the colors of the wires in this circuit? They got a tan wire from the sensor, but when you get to the horn, it's tan w/ blue stripe and then a purple one out. Doesn't make stuff easy to figure out.

 

[pnwboat]

The overheat buzzer is not normally connected to ground during normal operation. One side of the buzzer is connected to a 12 volt source. Usually the Red or Blue wire from terminal "I" (eye) on the ignition switch. The other side of the buzzer goes directly to the sensor on the head. The sensor case is the ground, and the bi-metal contact inside it is normally open. When the bi-metal contact in the sensor gets heated up to a specific temperature, it snaps shut and grounds the wire attached to it triggering the horn.

As far as the colors go, who knows what some previous owner may have done.

 

[bonzoso38]

pnwboat, I understand the operation. The grounding was merely to to test the horn operation as stated in the original post. In my most recent post I was just looking for a spot on the motor to test the horn rather than having to crawl up behind the helm station where the horn is.

 

[bonzoso38]

pnwboat, I understand the operation. The grounding was merely to to test the horn operation as stated in the original post. In my most recent post I was just looking for a spot on the motor to test the horn rather than having to crawl up behind the helm station where the horn is. BTW, no previous owners. this is the way it was wired from the factory.

 

[pnwboat]

Sorry ai mis-understood what you were asking. If you can't get to the terminals, just remove the sensor from the head and heat it up with a lighter and touch it to the block.

 

[bonzoso38]

Thnx pnwboat!