How do you get air out of the cooling system?

[Artago]

Hey all. My car is overheating and I think it's because there is air in the system.

The heating system blows cold air and the lower rad hose is not hot to the touch like the upper rad hose.

So how do I get the air out of the system? I've tried searching but I'm not coming up with anything concrete.

Thanks for the help,

Tom

 

[talonalex92]

Take the radiator cap off your car, start it and let it heat up. Its as simple as that!

 

[Artago]

Take the radiator cap off your car, start it and let it heat up. Its as simple as that!

Yeah that's what I thought. I did that and still overheating and cold air via the heater inside the car.

Any thoughts?

Thanks,

Tom

 

[1992awdlaser]

Take the heater core hoses off at the cooling system end. Leave them on the heater core. Spray a water hose into each hose. Hold it on each one until only clear water is coming out of the other one. This might fix the problem.

Did you let the car run until there were no air bubbles coming out of the coolant?

 

[DSM1G90]

Another trick is to drill a .050 hole in the T-stat flange. This hole helps in preventing airlock which is the hot air pressure under the T-stat before the T-stat opens up.

This will definitely burp all the air out of the cooling system and no more overheating issues.

All the T-stats that I've installed, I've done this trick.

I learned this trick when I used to have a Chrysler product with the 2.2L motor where the T-stat is located ABOVE the radiator line and mounted vertically. This is why Chrysler had those large allen plugs in the waterbox where the T-stat was mounted into - to eliminate the airlock.

But drilling a "peehole" in the flange (since their T-stats didn't have the wiggle valve which also prevents the airlock..) definitely eliminated this cooling problems of theirs.

-DSM

 

[Defiant]

Thermostats that don't have the vent visible are usually made with a divot in the edge of the valve disc.

DSMs don't need burping. Three heat/cool cycles and they will have all their air out, if any was left in to start with.

The bottom hose is cool because the radiator's cooled your water. If it's completely cold, you probably have a faulty thermostat. Replace the radiator cap at the same time.
I suspect you have a clogged heater core.

 

[blcknspo0ln]

Another quick way to check is to see if both of the heater lines are hot when the engine is fully warm. Both of them are located under the TB on the firewall and connect to the waterpipe + thermostat housing.