Overheating

I have an 02 tundra that's overheating on idle. I replaced the radiator and thermostat. When I see that it's overheating I add coolant and temp will remain good for a while until it starts overheating again on idle. I don't see any visible leak of coolant. What could be the cause?

 

If V8, see below...

• Could be a leak at the by pass hose for the throttle body.
• Could be a leak at the cross over pipe at the back of the engine.
• Could be leaking from hoses from oil cooler.

I see you have an access cab from profile pic. What engine? V8/V6? 2WD/4WD?

 

Ahhh I will have to check that out..
It's a V8 2WD

 

Sounds like you have air in the system and didn’t burp it properly. When you replaced the thermostat, did you properly clock the jingle valve between 11-1 o’clock? How did you refill the system, and was the heater ON in the process so coolant and air was flowing thru the heater core and associated hoses? Did you fill on level ground? Also, you used the correct fluid right? (Red or pink)

 

Yes I placed the jingle at the 12 o'clock position.
Yes the heater was on full blast when I was refiling it.
I believe it's pink fluid.

 

Since it is only when idling...Is your fan clutch free spooling? I think they should only spin 1/2 a turn at operating temp. Easy thing to check anyway.

 

That was my thought as well bad fan clutch. Is your AC working normally at idle?

 

Second the fan clutch. It should be very stiff and hard to turn when hot.