I have a 1990 Subaru Legacy that is overheating. It has approximately 300,000 miles. We have replaced water pump, thermostat, radiator, hoses, etc. The dye test has been done 3 times to check for head gasket porblems and nothing has come up. What else could it be. I have noticed that when the heat is on, one fan comes on, but the other fan never does. Can someone help me?
Im sorry but the dye test is an inaccurate one. Expecially if the car isnt overheating when you test it.A small amount of ehaust gas and tempature can affect the tempature of the cooling system greatly without being detected bye a dye test or even a gas analyzer over the neck of the radiator.
. How does the over bottle smell?
2. Are there any signs of oil residue in the overflow bottle?
3. How is the function of the cooling fans do they come on and stay on forever
4. Has the tempature of various spots in the cooling system been checked with an infared type themometor