iloveyulya1

guy i had a problem with my heater and i changed my thermostat. Then what i did i put all the coolant back and made sure it was clean plus i mixed the new at the dealer that i got. So i have a problem with my car, it over heats now. Im sure i got air in the system but i dont know how to get rid of it.. can someone help me, oh and picture would be better if someone has one

AudiMick

Run the car for a bit with coolant reservoir cap off until it gets warm and keep topping up the level should drop a lot when the thermostat opens.

Let it cool down some.


There are two hoses going thru the firewall to the heater core. One should have (o) marking on it. Loosen the clamp on that hose and pull it back slightly until the hole in the pipe is revealed.



Disconnect the sensor at the bottom of the coolant reservoir. Remove the screws holding the reservoir and raise it six inches or so. Re-fill with coolant until a steady stream of coolant comes out of the heater core pipe.

Might take a couple of tries to get all the air out.

iloveyulya1

when pulling out the pipe for heater core, do i need my car running or not?

mksu19

As AudiMick suggested, bleed off the cooling system. Park the car uphill, and turn the heater on full blast. You might have to do this a few times to completely get rid of the air in the system.

AudiMick

No, engine not running at that point.

As mksu19 has alluded to, you need to keep the heater core as low as possible.Parking facing uphill or lifting the front of the car is actually a pretty good idea. The problem is that air gets trapped at the top of the heater core.

turbo510

That seems logically backwards to me. If the car was tilted at all, I'd want to tilt the car's front down to eliminate air pockets in the head.

socalclimber

Or, car off, expose bleed hole(s), fill reservoir, use compressed air and a rag to create *some* pressure in reservoir (not a lot, don't want to blow hoses). This will force coolant into system and push coolant out bleed hole(s). Refill coolant and repeat if necessary.

I use a coolant pressure tester, but the idea is the same, get out the air pockets.

AudiMick

The reservoir is tapped into to the radiator top hose. The idea is is have the reservoir as the highest point in the system as the air will rise. Doing it the other way may trap air in the back of the motor and heater core.

The compressed air method works too.

turbo510

Normally the heater's firewall connections and the coolant in the reservoir are at similar levels, which is why you lift the reservoir when the bleed hole is exposed. Tilting the car up in front would have some effect on putting the reservoir higher than the hoses, but not likely as much as simply removing the screws and connector then lifting the tank. Anyway, I've always had the cars level and purged all the air. Also, regarding the recommendation to run the heater full-blast; there's no heater valve, so this won't have any affect on getting the air out.

AudiMick

Any car under 20 years old has heater flaps to control air going to the core. Running the heater at max does help with most vehicles.

Removing heat from the heater core causes a temp drop across the core. Warm water rises so this encourages circulation of coolant within the core.