So a month or so ago my radiator cracked toward the top of the radiator. The weather as been cold here in Denver so it wasn't an issue, the van never got above the half way mark of the gauge. I got a new radiator online and finally installed it today and now it over heats. The heat will go to the red line, drop some, go to the middle, stay there a bit, go back up. Its sporadic.

I do not think I broke any other lines and I don't see any leaks. I did not change my thermostat, should I? It wasn't overheating before so I didn't change it. Is there a heat control valve or something like that I should check? Also, tomorrow when it cools down I will run it with the cap off to make sure all the air is out of it.


I should have left it along until it started to over heat, I probably wasted my money on the radiator that had an insignificant crack. Oh well. Any help is appreciated.

 

is it full of coolant now? sounds like a air bubble

 

Model year? Cooling fan/s come on? Thermostat? Good idea to change it if it's been in there many years but not mandatory. Heat valve? Not on 96 and up.

 

Sounds like air in system that's why gauge is going up and down. Crack open some top hoses at their joins to release the air.

 

I got it! It was an air bubble. I just drove it up on ramps, took the cap off, and let if run for about 20 min. I then drove around in the mountains to test it and its good! Thanks everyone.