How to get thermostat to open

[rzaenglein]

Car has new thermostat installed very recently. Was working before I pulled old engine. I just pulled my engine and replaced it with another engine. I have a lisle coolant funnel on the crossover access, have the radiator cap removed and the front of the car on jackstands. Car heats up to normal temp on gauge, fans come on and I have the heater on high and have hot heat in car. hose below thermostat will not get hot! Has anyone else had issues getting thermostat opening? I dont really trust my gauge because Ive had the car overheat with the gauge reading normal before. its an 05 GT btw, I think they changed thermostat location at some point on the 3 valves. Anyone have any ideas? should I take the car on a short drive and see if that helps?

 

[BruceH]

Take it out and put it in a pot of water. Heat it up and watch it open. Is it possible to install the thermostat backwards in an 05?

The location was changed in 07. Some owners change to the 07 parts. I'd take it for a short drive in the neighborhood and see what happens.

 

[rzaenglein]

I know its installed in the correct direction, It was working ok before I pulled the engine, and I did not remove it from the hoses when I pulled the engine

 

[JeremyH]

You have air trapped in the system.

 

[skwerl]

My mechanic has an easy solution to eliminating trapped air in the coolant system. When installing a new thermostat, there is a small hole in the thermostat disc with either a cotter pin or some other small pin in it. He just cuts the pin off which allows trapped air to pass through the thermostat easier. Quick and easy and done. No more hours wasted trying to burp the air out of the system.

 

[rzaenglein]

I know there is air trapped in it, im just having one hell of a time getting it to burp. the hose above the thermostat is getting very hot but it still will not open. I think that is a good idea skwerl, I will give it a try.

 

[DRock]

keep squeezing the hoses as the car is warming up. it will get it to burp.

 

[86GT351]

My mechanic has an easy solution to eliminating trapped air in the coolant system. When installing a new thermostat, there is a small hole in the thermostat disc with either a cotter pin or some other small pin in it. He just cuts the pin off which allows trapped air to pass through the thermostat easier. Quick and easy and done. No more hours wasted trying to burp the air out of the system.

Need to do this on all engines. Also when you pull the T Stat to do this, Drop it in a pot of boiling water and see at what temp it opens. The Fan comes on at around 215 to 217 degrees. If the fan is coming on the rest of the system is working properly just have a mechanical issue with the system.

 

[86GT351]

Also when the car is running do you have the Heat on high with the blower on high? This helps generate heat in the engine