Subaru Repair: overheating 99 forrester, subaru forrester, head gaskets

Question
I recently purchased a 1999 subaru forrester. The car is great except for in the last couple of weeks i've been having overheating problems. I replaced the thermostat and once again the car ran fine for three more days and another 1000 miles, then again overheating. I have found that if I keep the motor reved around three thousand rpm's that or stay up to speed (around 55) that the temp. stays normal. I am at a loss. I have purchased a water pump for the vehicle as my next alternative but I am hearing alot about head problems with the 2.5L. the vehicle has 115K miles on it. What's next to do?

Answer
Hey Mike,

Check the coolant overflow bottle for signs of an oily residue inside the bottle,next smell the bottle and see if it has a fuel,exhaust or sulfur smell to it .If it does you probably have blown head gaskets.The reason its intermittent is it takes expansion of the cylinder head and gasket to allow some combustion chamber pressure and temperature into the cooling system.I know that is not what you want to hear but i hope it helps anyway.

Justin
All Wheel Drive Auto