Overheating issue

[Andrewc_21]

My 93 wagon has started to overheat while driving at slower speeds. When it is on the freeway going 60+ the temp stays just below the middle, but when I slow down the temp needle starts to creep up. When this happened, I pulled over to let it cool down and check the coolant reservoir to find it all the way up to the brim, but after 2 min or so it goes back down to the normal level. This only really happens after freeway drives though. There isn't an oily sheen on top of the coolant so I don't think it is the head gaskets and both fans are working normally, anyone have an idea on whats happening? Any info would be much appreciated.

[chanley2010]

You say the fans are working properly? That would be the first thing i would look at because at highway spped its being more air cooled then at lower speeds. Is this a manual or and auto? Possibly a sticky thermostat not fully opening? Any major work done to engine?

[Andrewc_21]

Other than the radiator I replaced about 10k miles ago, no major work I know of has been done to the engine/cooling system. The car is an auto. I haven't considered the thermostat though ill look into that.

[Andrewc_21]

So I made the trip to the dealership to get a subaru oem thermostat and gasket, installed that and flushed and burped the air bubbles out of the cooling system. Tried as hard as I could to overheat the engine and thankfully, was unsuccessful! Guess that fixed it thanks a ton for the tip

[chanley2010]

Hell yeah! Glad to hear it worked out for ya

[Legacy777]

Yeah, it sounds like you had air bubbles and/or a non-Subaru t-stat.