2002 Forester Overheating

Hi, my Forester started overheating today. I pulled over and let it cool down. The fluid was low, it took about a ¼ gallon to top it off. I was able to drive back home stopping a couple times and waiting when it got hot. The heater was blowing cold, then hot every minute or so and the temp gauge went up and down with it.
I hooked on my radiator funnel to see if I could purge out an air bubble. When I started the car it was bubbling like crazy. I’ll try to attach a video.
I’m hoping someone can tell me what it means.

That’s an indication of a blown head gasket.



I was afraid of that. Should I do other tests or is it definitely head gaskets?

That is the test.


Judging by the steam I think you have reached the boiling point, let the engine cool to 195 F before adding coolant. Turn on the air conditioning so the radiator fans operate.

Ok, thanks for the quick reply. I assume boxer engines have two head gaskets. Is it best to replace them both at the same time?

I let it cool to the c on the gauge, started it again and it started bubbling the same after about 2 seconds.


I’m afraid your luck ran out & you now have the infamous head gasket problem. You could try replacing the thermostat and the pressure-regulating cap, and verify the radiator fans are spinning like crazy when the engine is hot. Doubtful it will do the trick, still there’s a chance; and you’ll want those parts new anyway if you need to install new head gaskets.