subaru overheating- new radiator installed, seems like trapped air????

maybe the sending unit or the gauge itself is defective.

Have you pressure tested the radiator cap?

Chris

How do you know the car is really overheating? Is it simply the gauge that is telling you that the car is hot, or do you have other symptoms?

If it is REALLY overheating, you need to be sure that you are getting flow of coolant through the radiator, and if that were the case, the radiator should be pretty warm (read: hot).

A new thermostat should not be sticking, but it happens.. Also people sometimes install the wrong thermostat or in the wrong way.

And, it is possible that you didnt get all the air out of the system. When that happens, you can get strange indications of heating problems...

But for now, find out if you REALLY have an overheat situation or not. And we'll go from there.

Are you sure there isn't an air bubble in the system

Sounds like the thermostat has been installed 'facing' the wrong way (bass-ackwards).

And yes...I've done this before :-)

I've heard of people accidentally fitting the thermostat back-to-front. At the risk of asking a very silly question, why aren't thermostats made asymmetrical so they will only physically fit the correct way round?

Cooking thermometers are cheap at the grocery store--and come with long sensor-stems. They tend to tell the truth Just be careful opening a hot radiator. But, your rad. should not "not even be hot". Check both hoses--is one hot and other cool? If so, rad. is not circulating water. Sure would tell us a lot to know how hot that hot side is. Also, a mechanical temp. gauge is NOT a bad investment. HTH, s

Sorry. You have a lying gauge, a reversed/bad t'stat, a clogged heater core, a clogged radiator, a bad water pump, or head/head-gasket problem. Does it lose coolant? If so, quite possibly the head/gasket. The others you should be able to test and eliminate yourself, i.e. removing a lower rad. hose & watching flow-out as you fill top with a garden hose. Rig similar to check heater core. W/hoses attached, watch for water pump flow thru rad. while running with cap off. Just use logic and care to not get burned. s

Normally if you look at the thermostat you take out, it would take a real brain fart to get the new one on wrong. And, there ARE some that are basically impossible to get in backwards.

A basic level of automotive competence is, I guess, assumed (but not always displayed) by design engineers.

There is a sideflow type, I understand, that can really cause you problems if you dont identify it and replace it with the correct type. And that is not always obvious at your FLAPS application guide. I have never dealt with one of these, just heard of them.