MD7A temperature gage

[bfb]

I bought my cd30c October 2019 . The temperature gauge just moves to the beginning of white area after running for two hours. I measured the OHMS on the sensor and I get a difference between when the engine is cold and hot but don’t know if it’s the right resistance . I hooked up a jumper between the sensor wire connection and ground and the gauge went all the way up. I believe it is wired correctly. I suspect it is a bad sensor. From what I read on existing forums the pointer should be in lower quarter of the gauge.
Any suggestions would be appreciated

[mgphl52]

Is it possible the sensor is an alarm unit instead of a temperature unit???
Try pulling the sensor and putting it in a pan of water on the stove with a meter connected to the leads.
Check the value as you bring the pot past a boil. If it suddenly maxes out, it's an alarm sensor.
For a relatively small price, you can buy an infrared thermometer to validate a "new temperature" sensor.

[S/V Ethan Grey]

I had an overheating issue with mine and wanted to know what temperatures corresponded with the gauge colors. Here is my data. This will vary based on sender and gauge, so I don't know if it will be of any help to you. Eventually I want to change the gauge to one that outputs actual temp versus the white, green, red indicators. At 109F, the gauge was just at white/green mark. At 168 the indicator is at the green/red mark.

[Keith]

Mine is exactly like yours, the highest it ever gets is just into the white. I've been running it that way for 8 years with no problems.

Keith