Autos Fans

Why is my 2000 Mitsubishi Eclipse overheating?—by niupt2k

This is an extension of a previous question. The Eclipse is a 4 cylinder car with 110,000 miles on it. It overheats after driving for ~3-5 minutes in any condition. When it does go towards the (hot) side of the dial, the fan runs continuously. The coolant level is normal (just below full). There are no liquids on the driveway when it idles, there is no steam coming from the engine. The color of the exhaust is clear. Based off of previous responses, I changed a thermostat (the old one opened, but not fully). What are your thoughts as to what I should look at next? Other things that I have been instructed to look at is the water pump and the radiator. I would like to try to do it myself if possible. I appreciate your thoughts in advance.

Best Answer —by thebax20…

I’ve never seen a waterpump fail on a Mits, just the seals go bad and leak. Run the car up to operating temperature and watch the anti-freeze at the radiator cap filler to see if it circulates. The fluid should go up and down in the neck when you rev the motor.
You may have an air pocket, turn the heat temperature control to hot with the fan off. The air pocket will cause bubbles to rise out the filler neck, run the motor for 15 minutes with the radiator cap off, rev the motor and squeeze the radiator hoses to force the air out. You may even need to park the car on a hill with the radiator higher than the motor.
There is a chance that the radiator is plugged or you have a bad head gasket. I have never seen this on a 2000 4 cylinder Eclipse.
I have had new thermostats that were bad, it’s more likely you put a new thermostat in and it’s good, just an air pocket is there now and it creates a similar acting problem as a bad thermostat. Burp that baby!!!