car just started this 2 days ago drivin runs at about 170is but stop at a light by the time its green she wil be at about 230ish and coolant drips out of the rad cap, i put a new cap on and still does it?

 

Is the fan running when it gets hot? If it is not, then that is the reason for overheating, and you have to find out why the fan is not running.

 

yea, fans turn on

 

Your cooling system needs to be under pressure to operate correctly. Specifically, under 18 PSI of pressure, as that is what the radiator cap is rated to hold. It would seem to me that your rad cap is not holding pressure. Similar to how you can keep nitrogen a liquid when under pressure in a dewar flask, the coolant stays liquid because it is under pressure, even though it is hot. Also, if you have a leak somewhere in your cooling system that causes coolant to drip out so that you would not notice it, you could have an air pocket in the cooling system, which would lead the the rapid overheating when stopped. Though I recommend getting it fixed asap, you can try giving the car gas in neutral at a stop and see if the temp gauge goes down. You can also open the bleeder screws when the car is hot and see if you get coolant or just steam...

If I were you, I would get a new radiator cap, rent a cooling system pressure tester and pressurize the cooling system cold and see if you have any leaks, then I would completely bleed the system:

4th Gen LT1 F-body Tech Articles

Let us know how it goes.

Good luck and kill Rustanks!!!


x01660

 

well i put a new cap on, bled the system didnt have any air pockits. still running hot and even with the new cap i have coolant dripping out from under the cap?

 

I know that this info is for Hondas, but the info here is applicable to all liquid cooled 4 stroke engines:

Overheating: Symptoms and causes

Just from what is posted, I would check the radiator to see if it is clogged. Then check your t-stat. If not, check the oil for coolant and the coolant for oil as it might be a blown head gasket...

Good luck and kill Rustanks!!


x01660

 

well no coolant in oil or oil in coolant, im going to get a new t stat and another new rad cap and see what happens.

 

flush the radiator, heater core and engine.