How do i purge cooling system for 3.5 intrepid 2002?

When you changed these components and refilled the cooling system, did you purge the air out of the top of the system by opening the bleeder valve. These engines have coolant in areas higher up in the engine where air can be trapped during refill. Air trapped in the system will cause overheating issues. Otherwise, the only thing you haven't mentioned in the system is the radiator and fan assemblies. They could be suspect, as could a possible blown head gasket.

What size motor?

first check the coolant level refill if its less, bleed the coolant there could be presence of air in your cooling system, the bleeder is on the top of your thermostat housing.
2. after bleeding and still overheating, check the cooling fan if its working or not when the temperature hits 90 deg.
3. check radiator it might be clogged and dirty thats why water can not properly circulate.
4. if still overheating remove thermostat valve and observe.
5. after doing all those tips and overheating still persist the next possible cause is your water pump must be worn-out.

If it's overheating in a matter of minutes from cold, it is probably not the fan or fan switches. If the gauge goes up that fast, it is often because of air in the system. When hot air hits a water sensor, the gauge will skyrocket. make sure the radiator is full and open any bleeders in the cooling system (if it has any) to purge all of the air out. Also, try turning on the air conditioner -- that should start the cooling fan -- to see if that makes a difference. One more thing: just because a part is new, don't assume it's good. I once saw a car overheating with no heat and a full radiator (classic water pump) with a new water pump on it. We took it off and realized the impellor (blades) was loose on the shaft! Good luck.

make sure that the system has been bled of all the air to do this there should be a little bleeder screw near the thermostat housing open this up until water comes out start the car and turn the heater on high watch for any air bubbles to come out of the bleeder until it is straight fluid coming out see if this fixes it, also check the radiator cap this could cause overheating too, if this is all fine check the fan switches to make sure they come on at right temperature.

Possibles.
1. Failed Water Pump..... Separation of the Impeller and Drive shaft, or coolant leak from the Pump body gland, or associated hoses in the Cooling system
2. Clogged External Radiator Core..... This can be a common problem, dependant on geographic location. Dirt, Straw, etc, gets trapped in the core tubes reducing the Air flow.
3. Failed Electric fan Power supply. Check Main services Fuse box for blown fuses on the A/C fan and Main engine fan. Again lack of through air flow will cause overheating.
4. A Main Fuse Box services supply MAXI fuse has Blown.
5. The Temperature sensor that operates the Engine fans has failed. This unit completes the circuit to the relay in the Main Fuse Box that energises the fan motors.
6. Fill cooling system, leave pressure cap OFF, run engine and look for excessive air bubbles while air is purged out of the system. Keep topping up until coolant overflows, then run up to normal operating temperature, top up as required, and the fans should start up.

ALTERNATELY, AFTER TOPPING UP COOLANT AND WITH THE ENGINE RUNNING, set the controls to MAX A/c and Blowers on Full speed, after the A/C compressor has cycled for about 30 seconds, the A/c condenser fan should start up to cool down the Freon in the System and at the same time operates both fans. If this has no effect go back up the check list, and systematically eliminate each phase.
HOWEVER, if it is none of the above, then you may have originally "Cooked" the engine, and warped the "Head" or "Perforated the Head gasket.

Best of luck with your endevours,
Regards, DT.

2004 dodge intrepid cooling system purging valve

Sir,
Low coolant? 
Cooling fan not working? 
Radiator plugged or air flow restricted? 
Defective thermostat? 
System air bound? 
Water pump not circulating coolant? 
Defective radiator cap?

Occasional overheating, if not related to low fluid or other problems, is usually caused by a sticking thermostat. 



Thanks Good Luck
Appreciate to rate as "Fixya"

You need to remove the upper most heater hose from the heater core and raise the hose up high . Fill the rad until coolant comes out of the heater core pipe. Carefully reattach the heater hose. Fill the rad slowly allowing trapped air to escape.This may take a while. Once the rad is full put a catch basin on the floor under the rad filler neck.Start the car and let it run to operating temperature.Allow the expanding coolant fall into the basin.Once you see circulation in the rad you can slowly top the rad off.Once you do this replace the rad cap and fill the reservoir bottle 3/4 ways to the top. Shut the car off and let it cool off filling the bottle as necessary.It's a lot to do,but it works for me every time :-)

The part that broke off is the cooling system purging valve housing. I had the same problem. Apparently, these engines' cooling system must be purged whenever you allow ANY air in, for example, if you let it run out of water due to a leak, or you make any sort of repairs on the cooling system where you had to drain the coolant. Basically, if there is ANY air in the cooling system it will turn into a steam chamber creating too much pressure. Did you have a hose, radiator, thermostat or coupling changed recently? Be sure to purge the system and you will solve the "pressure cooker" issue. Good luck.