Changing thermostats and broke a sensor on the port side of the thermostat housing. There's another sensor on the starboard side of the thermostat housing. I'm sure 1 is for the temp gauge but what's the other one for?
I tried looking on this site but no luck: https://www.mercruiserparts.com
They are 1990 454 mag engs with "new style" thermostat housings.

Thx

Found this page: http://media.channelblade.com/EProWe...ng%20horns.pdf
Maybe the "other sensor" is a over-temp warn switch for the warning horn?

one is for the alarm system.

Thx for confirming. Any idea where I can order 1 online? I've been searching the net for a while and came up with nothing.

Its in the Audio Warning System section for your engine. Its #1 in the parts list
https://www.mercruiserparts.com/bam/.../31808/961/320

Thx Griff.
Don't know how I missed that.

I went thru the wiring for all 3 sensors that can turn on the warning horn on both engs and all looks good. I would like to verify the coolant temp switch works properly (on the eng I didn't break the sensor). Anyone know what temp the coolant temp switch is supposed to close?

The alarm will sound right around 195-200* from what I remember

Thanks again Griff.