Engine Coolant Temperature Gauge question

[thejimrose]

>
> Question 1:
> Should the thermostat keep the coolant temperature relatively constant?
> Even
> at low temps and highway driving?
>

yup. mine  is always  rock steady  on the 1/2way mark on the gauge. from 110
in sonoma to 15 in tahoe.

Question 2:
> What is the usual position of the needle when driving?


1/2 way on the gauge.

And what is the
> position of the gauge when the radiator fan kicks in?


no change on mine.

Question 3:
> I think the dots for positions 1 and 7 are calibration test marks. If I
> remember correctly, the Bentley shows usage of a "Special Tool" to test
> the
> gauge. More than likely the tool is just a rheostat. Does anyone know the
> resistance values at the two test positions?
> Answer: not me.


me neither.

Question 4:
> Does anyone have a simple method of measuring the coolant temperature with
> an external thermometer?


laser thermometer  hitting the engine /  radiator at various points? but
agreed, the temp sensor is the right place, coming out of the block.

>
> Answer: You need to read temp of coolant inside the engine or 'read'  the
> temp sender.
>
> Conclusion: Get a new thermostat. Didn't we just do this one?


+1. might wanna flush the coolant, change the temp sender too while you're
in there.