i have noticed a water sound coming from behind the dash since i bought this forester, i've asked around on the net and everyone have pretty much agreed its air in the heater core.
i've been told to bleed the air out of the system by taking off the radiator cap and starting up the engine, wait for the air to burp then add more coolant.
problem : when i try this the radiator starts to overflow from open cap.
question: i've noticed a little plastic screw up the far upper right side of the radiator. its a flat plastic looking screw with a philips head. is this the so called "bleeder valve" ? does this have anything to do with bleeding the air out of the system?
can someone please explain this process. thanks!!!
car: 1998 subaru forester S