Retrofit low coolant warning.

[DannyC]

Hello this is my first post. I have 1980 chevy c30 rust free that has been garaged all its life I purchased it new. It has 502 HT crate motor, serpentine belt conversion with 4L80e Transmission. After my overpriced Griffin radiator failed less than 2000 miles leaking out all the coolant, I was wanting to add degas tank (expansion tank) with low coolant sensor not overflow tank. I was thinking of putting expansion tank where battery is and moving battery to other side. Has anybody ever done this? How would you plumb line in?
Thanks Danny

 

[SirRobyn0]

@DannyC First of all there were lots of these trucks that rolled out of the factory with overflow / expansion tanks, mounted low as in lower than the battery, bottom of the core support tucked up close to the radiator on the battery side which is where my factory tank is located.

For one with a light I'd suggest either using a tank that came factory with a sensor in it, or use the "toilet tank" type sensor out of a vehicle that it is removable from and install it in a factory square tank. If I were doing it, I'd by a factory tank for a square from the mid-80's, mount it in the factory location so I didn't have to move the battery and then I'd buy a sensor and grommet style seal for a mid-90's Jeep Grand Cherokee. Drill the required hole in the top of the tank and install the sensor. For the light I'd repurpose one of the lights either in the speedo or fuel gauge to be for low coolant. As for the wiring the Jeep sensor is two wires, so you'd need to start with a key on positive wire at the light, run the other wire from the light to the sensor, and then the remaining wire off the sensor to ground. There would be no key cycle test for light (such as lights will sometimes come on during cranking to test), but it would work when the coolant got low.

I'll end this by saying I have not done this modification, but I do know how a basic low coolant light circuit works.