Thermostat Test Procedure Using Glycol
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
Inspect the operation of the thermostat by hanging the thermostat on a hook in a 50/50 percent solution of DEX-COOL® and clean drinkable water.
In order to inspect if the thermostat valve is opening properly, perform the following test:
Completely submerge the thermostat in the glycol solution. The solution should be 11°C (22°F) above the temperature indicated on the thermostat valve.
- Thoroughly agitate the solution. Under these conditions, the thermostat valve should open.
In order to inspect if the thermostat valve is closing properly, perform the following test:
- Completely submerge the thermostat in a glycol solution. The solution should be 6°C (10°F) below the temperature indicated on the thermostat valve.
- Thoroughly agitate the solution. Under these conditions, the thermostat valve should close completely.