Hello,
I'm having some coolant weirdness with my 2002 Subaru Forester. I'll give you a brief history of what's been done and what I'm seeing now.
In March of this year, I had the head gaskets replaced and the 140,000 mile service done including everything that should be done with that maintenance, timing belt, etc. In April, during a trip from SC to FL, I had to have my radiator replaced. The mechanic did the test that showed the heads were not leaking, I can't remember the name but he put a device in the top of the radiator and showed me the color of the fluid and explained how it should change colors and all that.
Since then, I've noticed odd coolant things, most recently with the radiator pushing all the coolant to the overflow tank and not taking any of it back in. This happened once or twice in June, and I took it to my usual mechanic and he could not replicate the problem. I moved from SC to CO in early August and during that drive, the car overheated and all of the coolant was in the overflow tank. I put it on a tow dolly and towed it out here.
This week, a mechanic friend and I replaced the thermostat (OEM part), thinking that might be the issue. In the last few days I've driven it with no problems, but I'm noticing that where the hose meets the radiator cap, there are bubbles coming out of that connection with a fizzling sound and a very small but noticeable coolant drip at that connection.
Edit: I should also add that there are sometimes bubbles in the overflow tank.
When we drained the radiator, we kept the coolant and poured that back in as we burped the system. We did not drain the overflow tank and it is definitely still way overfilled, way past the full line, but this is full from before our repair when the problem originally started. It pushed all of that out and didn't take it back in. Now that we've done this repair I've seen the coolant rise and fall, but very little since there is already so much in the tank.
Any thoughts on all of this?