I think we should get a confirmation on that. He may have more than one issue. If the first problem was that the fluid was initially low, then the pump and radiator were probably OK and adding more fluid would have solved the problem.

However, if the new thermostat was installed upside down, the temperature sensing mechanism would be on the cool(er) side, and the thing would run hot.

Somebody got an old engine handy?

 

Ok, So I feel stupid. I was out of town when it started overheating and based on my daughters description and the full reservoir tank, I assumed there wasn't any water flow. I never checked the radiator!!!!

I ended up putting a gallon of 50/50 in it to top off the radiator. Then ran it for a while and added more to top it off again. Then I ran it for a while with it not going above 210. Then I drove around the neighborhood (30mph and hot out), and even stopped in the sun a few times to simulate a stoplight. It stayed at 210 or below.

I can't believe I never opened the radiator cap to check the actual radiator level.

Thanks guys.

 

No worries!! 99% of vehicle owners do the same thing! And 98% of the time they're right!!

 

I'm pretty certain that the arc over the face would prevent entry past the inset lip when trying to insert backwards.

 

Don't forget to run it with the heat on and blasting high for a while to circulate the full system, then once it is cool top off at the radiator once more. That should do it.

 

Yep. Did it. Thanks.

 

The 99 lacks a heater core flow control valve so the core is full flow constantly. No need to run the heater to bleed the air out. It is an effective thermostat bypass.