I recently purchased a 1985 GSL and noticed a few mods done to the radiator sensors. This came to my attention because the "Add Coolant" warning light was staying on all the time, however the temperature gauge was running in normal range and the actual level in the coolant reservoir was within acceptable range as well.

The mods are as follows:

1. No Coolant Level Sensor on the top of the radiator, just a plug which appears to be stock.

2. Wire for Coolant Level Sensor shorted to chassis ground.

3. No provision for Coolant Temperature Switch on the radiator.

4. Wires for Coolant Temperature Switch shorted together.

Also, when feeling around for the nonexistent Coolant Temperature Switch on the bottom of the radiator I could feel two tubes capped with plugs.

I'm thinking that the original '85 radiator was replaced with an earlier model that still had the oil cooler on the bottom. This would explain the capped tubes and lack of mounting for the Coolant Temperature Switch. However, I don't understand why the Coolant Level Sensor would be shorted to ground.

Here's a photo:


Any help would be greatly appreciated!

 

The tubes at the bottom are for an auto trans cooler. Almost all replacement radiators have this.
The coolant level sensor is grounded, to keep the light/alarm off. Whoever installed the replacement radiator likely ruined the 2 sensors, and rather than replace them, they just rigged the wiring. I would bet the plug at the top was the shipping plug that was put in when the radiator was manufactured.

 

lol i have pretty much the same thing from a junkyard radiator.

 

I didn't believe it was true, but I have seen some radiators that I believe were the original oem ones with the trans cooler tubes. Almost all aftermarket rads come with them now days, cuts inventory stock in 1/2.

You should be able to find the 2 sensors if you post a wtb in the for sale section. Iirc, the bottom sensor is for the hotstart assist. If you have the rats nest removed leave it jumpered.

 

Thanks for your responses! I've had internet problems and couldn't get online for a couple days.

Will look into replacing the sensors.