water temp sensor question

[sam winfrey]

1997 Mercruiser 4.3LX GEN+. I am replacing my thermostat and cooling hoses and when I pulled off my thermostat housing I had one plug and 2 water temp sensors. The sensors are different and I cannot find a part number on either one. I have a manual and I have looked online at every parts diagram and wiring diagram I can find and nothing shows that 2 sensors are required or which one is for. Just wondering if anyone could clue me in.. thanks in advance.

 

[Bondo]

Re: water temp sensor question

Ayuh,... 1 is the water temp Sensor(for the gauge), 'n the other is the overheat Switch(for the alarm)...

 

[adeneo]

Re: water temp sensor question

You can find what you are looking for and even order the parts right here!

I believe the water temp switch is part #48952
and the temp gauge sender is part #49734

 

[sam winfrey]

Re: water temp sensor question

I saw both of those parts on the diagram but I never took a step back an looked outside the box.. thanks again guys.

 

[scoflaw]

Re: water temp sensor question

And if its fuel injected which 1 does the ECM get its signal through?

 

[adeneo]

Re: water temp sensor question

Depends a little on the MEFI system and what engine it is, you should refer to the wiring diagram for your engine, and preferably without hijacking threads, but for MEFI 3, just from memory, I believe the temp switch has two wires, one connected to ground and one to the J2-11 pin on the ECM, if that helps any ?

If you have the engine serial # you can use that on Mercury's parts express page to find the right parts, or try posting a new thread with all the information you have on the engine, and surely someone will have an answer to your question!