Is there anyway to test a thermostat. I have a fan that isn't kicking on and I am doing a process of elimination. I had coolant running out or the reservoir the other night and some of the help that I got from an other post was to check the thermostat, them move on to the fan swith. I got the thermostat out and would like to know how to test it.

 

if you have the thermostat out in your hand you can put in a pan of boiling(almost) water and you should see it open up. if it does you know it works im not sure the temp is that opens it but assuming at least 160.

 

Should be full open at 190F.

 

i had that problem and it turned out to be dirt lodged in the fan i took out the fan and hooked it up to a car battery and it broke the fan loose because it runs fine now.