Overheated in my driveway...... cooling system questions???

[Dirtyjersey]

Hi guys, I own a 2004 x5 3.0 with 109k. Car was running for a few minutes after a trip to the supermarket. It was about 40 degrees outside. It overheated at some point and ran for likely about 1-5 mins after spewing coolant all over........ Upon inspection, the mechanical plastic fan disintegrated and threw pieces of plastic all over under the hood. It took out the fan shroud, plastic ps pulley, the coolant tank split........ I understand that the car had a lack of ability to cool with no fins on the fan, but my questions are as follows:

1. Why did the fan break this way?
2. Why didn't the electric fan come on and take care of everything?

I know the potential disaster of engine/head warpage, etc.....my fingers are crossed........

[g300d]

What parts of the fan broke off exactly, and did the water pump pulley break off with it? They are both plastic, and knowing what exactly broke and where will help determine why.

If your expansion tank was damaged by your self-destructing fan, you start losing coolant. No engine fan plus no coolant = overheating that the electric fan wont be able to contain.

[Dirtyjersey]

Just the plastic blades broke off the fan. the fan clutch and water pump are still intact. I replaced the fan clutch anyway just to be safe. And the split in the tank was on the opposite side of the fan, and seems to be from it overpressurizing, not an impact from the shrapnel...... That's why i figured the overheating was from the lack of mechanical fan functioning?

[g300d]

Interesting chain of events. Kind of hard to trace because even when not overheating, our expansion tanks are notorious for killing themselves often.

Is your electric fan working? You can force it to turn on by engaging max AC.

About your mechanical fan, have never encountered even anecdotes of that kind of failure yet. Our more experienced members may be able to shed more insight on it.

[Dirtyjersey]

I'll have to check that, thanks for the tip about the AC!

[tmv]

Your fan clutch seized. It spinned too fast and the plastic fan broke off from the water pump pulley. It's not uncommon on a bimmer from that era, especially the E39.
The electric fan in the front is only an add-on to the mechanical fan. It's not sufficient enough to cool the radiator.

Hopefully no serious damage occurred. Good luck.

[Dirtyjersey]

I like that answer! Since I replaced everything mentioned...... Like I said, fingers crossed!!!! Thanks everyone!

[g300d]

Ah. Thanks tmv, learned something new today.

[Ricky Bobby]

Originally Posted by tmv

Your fan clutch seized. It spinned too fast and the plastic fan broke off from the water pump pulley. It's not uncommon on a bimmer from that era, especially the E39.
The electric fan in the front is only an add-on to the mechanical fan. It's not sufficient enough to cool the radiator.

Hopefully no serious damage occurred. Good luck.

^^^Bingo. Mine was making some horrendous noises about a month after I bought the X, had it replaced along with tensioners and belts, been fine since. The fan clutch is often overlooked but at your age and mileage is about the life cycle I've seen for it.

[Dirtyjersey]

Originally Posted by g300d

Interesting chain of events. Kind of hard to trace because even when not overheating, our expansion tanks are notorious for killing themselves often.

Is your electric fan working? You can force it to turn on by engaging max AC.

About your mechanical fan, have never encountered even anecdotes of that kind of failure yet. Our more experienced members may be able to shed more insight on it.

Everything seems ok, but my max AC wouldnt come on? Maybe since the car knows it was only 30 degrees in NJ over the weekend? So still no signs of life from the electric fan, but it hasn't overheated either.

I do have a new minor annoyance noise though, it sounds like a chipmunk chirping or something from my pulley system? I can't narrow down exactly where the noise is coming from....... but if my fan clutch goes again, I'm taking a baseball bat to the car!

Anyway, thanks for the assistance!