Subaru Repair: 1996 Subaru legacy wagon overheating problems, Subaru head gasket help

Question
I've replaced radiator hose which burst on me, alternator which was messing with the heat over the winter, flushed out the radiator.  After doing each of these things the overheating would stop for a while but returned shortly after.  i still need to replace the thermostat, but today after about a 300 mile road trip the car over heated, stopped and unscrewed a little plastic screw on the left side of the radiator and it poured out steam for about 3 mins.  then with the screw off it guzzled down about a gallon of water. i would poor some in, and steam came out the screw hole.  after about 30 mins we started the car and it was cool again, finished the last 40 miles and unscrewed it again and a gauzier shot out.  I'm getting tired of this overheating stuff, please tell me that replacing the thermostat will fix it.

PS my radiator reservoir has cruddy brown liquid in it mixed with the anti freeze and water... i cleaned it out, but its back again. WTH is it????

Answer
Hey Cris,

I would start with reading my article here.

http://allwheeldriveauto.com/subaru-head-gasket-problems-explained/

This is an in depth explanation of the problem and cure.

If I can help you further after that I will try.

Justin

Independent Subaru Expert