How To Test A Car Thermostat In Hot Water

[Morrissette]

How do you test a car thermostat with hot water? I've heard it's possible, but I have no idea how.

 

[More Green]

Take the thermostat out of your vehicle, boil some water and then put the stat in the water. If it opens, it's good. If it doesn't, buy a new one.

 

[IH tractorman]

you can use a cooking thermometer to see what temp it opens at

 

[Tommy63]

Actually you don't want to put it in boiling water. You'll want to see if it open before the water boils. Throwing a 160 or 180 degree stat into 212 degree water has a 32 degree error possibility. Put it in water turn on stove read water temp with cooking thermometer when it opens. If it NEVER opens throw it away. The opening temp should be stamped on the thermostat.

 

[Qapla]

Checking to see if it opens when the water reaches the correct temp is a good/valid way to troubleshoot a problem. Like those above have said it is easy to see if it opened.

However, for as little as they cost ... if you are taking it out to test it why not just replace it while it is out instead of putting the old one back in?