3.7L Temp gauge question

[mdlee]

I don't trust the electronic temp gauges on my Mercruiser 3.7L so I added a mechanical gauge. I put the thermo unit in an empty plugged hole right beside the thermostat on the exhaust manifold. My question is will this give me a good reading, or do I need put the thermo unit in the block?

 

[rebars1]

Re: 3.7L Temp gauge question

If that hole was intended for a temperature alarm sensor, you should be OK. Maybe have both devices hooked up (with two guages) and compare the temps until you are confident that it works.

 

[Big Boat Bay Buster]

Re: 3.7L Temp gauge question

Thats exactly what I did with my 470. I had a mechanical temp gauge laying around for test purposes and put it just where you did. This confirmed that my electric gauge was off. Mechanical gauges are the most accurate. I replaced both the sending unit and gauge(electrical) since they were 25 years old. All was good after that
Chris

 

[mdlee]

Re: 3.7L Temp gauge question

Thanks Fellas.. It seems to be working well.. I feel better knowing someone has done the same thing. And sure enugh the electronic gauge was off.. the motor runs colder than the electronic gauge reads. I just instaled a new riser.. I think all is well.