Car Overheated, Coolant brown milky mixture, radiator or blown head gasket?

Hi everyone,

Just bought this car about 9 months ago, and everything has been fine with it until I was driving yesterday and the coolant light came on for a second (I didn’t know what it was at the time but the light went off a few seconds later).

I parked my car got what I had to in Target and tried finding out what the symbol meant. On my way back the same coolant symbol came on and then my car started to overheat. I quickly pulled off to the side of the road, opened the hood and there was a brown milky mixture all over the bottom of the hood and all in the engine compartment.

I opened the coolant cap and it was empty but was not clean at all, it was the same brown milky consistency (I haven’t filled or drained the coolant since I got the car)

I asked my friend who is BMW certified and he says it’s the head gasket that is blown but the car runs fine if you put water and coolant in it. I brought it to a uncertified mechanic down the road and he thinks its the radiator that needs to be replaced.

The engine and dipstick oil looks the way it should be and the same milky consistency isn’t in the engine.

WHAT SHOULD I DO? Replacing the head gasket was priced at 18 hours roughly $1500 on top of parts...

Run a clean coolant mix, and check it after a day. Maybe the previous mixture was brown for some reason.
The head gasket takes under an hour to do, and the part isn't expensive. Where did you go? Kia dealership?

My friend did the same thing, I replaced his upper radiator hose, filled and bled the system and his ran fine.

Usually thats a really bad sign, but somehow his car ran just fine and had no problems. He ended up getting rid of it a few months later but it ran just fine up until then. So not sure how it ran in the long run.

Originally Posted by //TRD power

The head gasket takes under an hour to do, and the part isn't expensive.

I'd like to see this.

Originally Posted by 330ciandr6

I'd like to see this.

He must be thinking Valve Cover Gasket

Ok thanks you guys, whose thinking valve cover gasket? My friend said, the Head Gasket.

TRD Power said a head gasket could be replaced in about less than a hour - no way. Folks were just pointing out that a valve cover gasket could be replaced in about an hour and that is what TRD Power was likely referring to...

Oh yeah, I don't know where he got valve cover gasket from

the only thing to keep in mind is that if the PO used Zerex - G-05 which is an approved coolant, its more of a beer color, which when it gets dirty would probably turn brown. When I did mine between the Zerex, the Blue and and Green it was quite the interesting color. That said, milky is another problem i suppose unless you had the totally wrong coolant. I would maybe try a cooling system flush and overhaul, including a new water pump and thermostat and see. If you blew your head gasket (IIRC) you would have oily coolant, shitty power, and a lot of smoke.

Oh yes sorry was thinking valve cover. Oops.

thanks jgold, would I be able to install a water pump and thermostat on my own or is there a lot of programming that needs to be done after the installation?

Drain all the coolant from the engine block plug (enough DIY's on here) - check for oil in the coolant.

Drain all the oil - check for coolant in the oil

In both cases the visible signs will be a milky brown streak through the liquid

If you find it in either I would suspect the head gasket blew when the aluminum head got too hot.

If you suspect the head - go to a local shop and have them to a pressure test.

Changing the head gasket may not fix this - if the head warped from the overheating.

There are lots of threads on here about overheating including mine (325 cab)

I was lucky and the head did not warp - others have not been so lucky.

I will attach a PDF that is a BMW SI for checking the overheating damage of the E46.

Typically if this pipe is melted BMW determine that there was sufficient heat from the ovberheating to cause substantial engine damage.

OP... is ur sig car on OZ Energy's?
(not trying to threadjack lol just curious)

Are you talking to me? Idk what OP means or 'sig' or OZ Energy or threadjack

BMW North beat me to what I was going to say.

However in the event you find your car overheating again, do the obvious and pull off to the side of the road. Instead of turning the car off all the way, keep the key in position 2 and turn the heater on high. This will help the engine cool and may even save a few people from getting warped heads.