Adjustable thermostat probe location

[kmoses]

I have installed a adjustable thermostat/cooling fan control control. There were no instructions about the probe location. I have seen posts with the probe going completly through the radiator, half way through and some with the probe inserted inside the top radiator hose. For those who are using this setup, what has worked best for you? Currently, the probe on my car is centered beside the top hose inlet.

[azruss]

Is the new thermostat part of the radiator. If so, what did you do with the recirculator bypass.

[kmoses]

I didn't replace the coolant thermostat, I replaced the preset cooling fan switch with a probe type adjustable thermostat switch to turn the cooling fan on and off at a temp. I could choose. I tested my stock cooling fan switch in a pot of water and it worked fine but once installed in the aluminum radiator the temp. gauge was getting in the red before it would turn the fan on.

[So Cal Mark]

the probe needs to be inserted fully into the radiator fins

[RRoller123]

These schematics always seem to help a bit in these discussions.

[kmoses]

As per. Mark's instructions, probe inserted fully into radiator. I added a rubber cap to the end of the probe to insulate it from cool air.

[So Cal Mark]

the probe should be pushed into the fins so that only the tube is seen, otherwise it won't be accurate

[RRoller123]

The thermocouple junction is out in the bulb at the end?

[kmoses]

I found this PDF instruction sheet for a cooling fan controller that has a bulb and capillary tube like the one I'm using.

https://www.flex-a-lite.com/pdf_instruc ... -99936.pdf

[DieselSpider]

The instructions on mine said to strap it flat to the engine side of the radiator just below the header tank using the provided nylon tie straps.

I could not bring myself to disturb the fins or tubes on that old radiator so I just used the ties provided to strap the probe lengthwise along the upper radiator hose. Works just fine and there is no chance of damaging a delicate radiator or starting a galvanic reaction between the two dissimilar metals.