As the title says, my car seems to overheat, and I can't find the source. I replaced the radiator with a new Mishimoto aluminum radiator, put in a brand new thermostat and gasket, and made sure there was enough coolant. The other day, was driving and heard a loud whining sound coming from the car. Got home a minute later and saw coolant all over the engine bay. Coolant reservoir tank was full, radiator was losing coolant. Any ideas what could be causing the overheating?

 

A couple of quick questions;
1: Any white/ blue smoke coming from your exhaust pipe?
2: Was the car correctly "burped" (getting all of the air bubbles out of the cooling system) when the car was refilled with coolant?
3: Do you see any black soot around your engine bay? Via valve covers, crankcase ventilation system areas, pcv valve, or even in your actual exhaust pipe?

 

Not sure about the white/blue smoke, but I thnk there might be. I have an open downpipe until the weekend so I can't really tell. Car was correctly burped. Cycled it a few times through, about 15 minutes to make sure I got all the air bubbles out of the cooling system.

As far as black soot around the engine bay, I have not seen or felt anything. I've been working on it installing the new radiator and didn't see anything out of the ordinary.

 

The same exact thing happened to me after a coolant flush. The first time I filled the cooling system with fluids and thought I got all the air out, but took it for a drive and it puked coolant everywhere.
In the end, I spent at least 25min checking and filling the cooling system with fluid and it was fixed. Apparently Subaru cooling systems trap a lot of air if not done the proper way.

 

Really? Interesting. I'm gonna run the car for 30 minutes tomorrow then to make sure the air bubbles are getting out and the radiator is filled. Thanks for the info Krazy.

 

I run mine for an hour or so with the heater on. I use a "no spill funnel" to make it easy.

 

Just checking to make sure you didnt end up blowing a seal and or gasket. Im currently dealing with a similar problem but i ended up cracking the head of my wrx (may she rest in peace) and in the process of having to either rebuild or buy new.
I hope you find the solution before its too late.. Overheating can lead to blown head gaskets

 

Just ordered a no spill funnel on Amazon. Seems to make the job much easier and cleaner. Do you have the fan on or just set it to the hottest setting without turning on the fans? I've read people do it both ways. And yeah, gonna definitely run it for extended period. I really don't want to blow a head gasket or anything else for that matter.

And yeah, I heard the engine can completely seize rendering it useless so I want to avoid that at all costs. I can't afford a new engine or car at the moment. Thanks for the input guys. I'll see if this fixes the issue.

 

you can also try doing it on some ramps or on a slight hill. you want the front radiator cap to be at the highest point. engine takes a while to suck the coolant from overflow tank back in. I did it a few times, until I didn't need to fill it anymore. after driving it around for a day or two, filled overflow tank and radiator again (a few ounces) and the level never went down since. honestly, it sounds like there is still air in there with possible leak somewhere (cap, hoses, maybe even crack in radiator)

 

I ended up buying one of those funnels just for my Subaru too. Makes filling much cleaner and easier. I think you turn the heater on the hottest setting and the fan to a low setting while the engine is running.

 

Squeezing the upper radiator hose cad dislodge some air bubbles too.

 

Alright, spill-free funnel came in today. Gonna set it up and let it idle for an hour. Hopefully no more overheating issues. Thanks everyone for the input, will update this later with results.

 

You might want to also check your clamps since you are leaking. Every time you loosen one of them, they lose their strength.

 

Also check the rubber seal around the the radiator cap and turbo over flow box cap thing.My buddy had similar issue and we finally noticed the cap was old.

 

I am also suffering from can't-burp this damned thing-itis...

Gauge hits red before the stat opens (known good) and I stop engine to save the HG's...so mad now.