bleeding air out of system

[ratmn218]

1996 cavalier 2.2 liter, getting heat out of heater, but nothing going threw radiater, lower hose is cold i think its air locked. what is procedure for getting air out of system? i see 2 air bleeders 1 on heater hose other on top of motor.

[Macgyver55]

I usually open the bleeder screws on the thermostat housing and the heat tube while filling the system then close them. Then I run it a bit, open them again and bleed until water comes out.

Repeat this process a few times after running a bit more to insure all air is gone.

It is important on this particular motor to not have air in the system, but, if you are getting heat, and the car is not overheating it seems likely that it is ok.

[ratmn218]

do you open bleeder screws while running? or off with pressurized?

[Macgyver55]

I usually do it while running. Some guys do it after running it and shutting off. I think either way will eventually give the same result.

[Jeremy airjer W]

Are you sure the t-stat is opening? It will take a while for the vehicle to warm up enough, especially in the cold, to open the stat. Even in the shop it can take 20 - 30 minutes of idling time to get them warm enough to open the stat.

[ratmn218]

im thinking that was my biggest problem yesterday

[BIG DS]

Probably a t-stat. Very important to use only a AC-Delco stat. The aftermarket ones do not work properly for this motor.