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Overheated 2004 xi high milage car, Need Advise!!

8K views 27 replies 14 participants last post by  yo_marc 
#1 ·
Hi all,

So my car had this problem when I would turn the heater the radiator light would come on and then turn off after turning the heater off. (I was planning to take it for a leak test....)

I was driving it on freeway and turned on the cooler and the radiator light came on and stayed on this time. I stop at a gas station to put gas and check things, and I saw the car leaking form the expansion tank. I drove the car to a street but right before I turn of the car the temperature gauge reached the beginning of the red part.

Long story short, dad came and we put a glue (recommended by O'Reilly) on the expansion tank with a non BMW coolant. We tested it, and it was still leaking a bit from the glued location. He drove it back home, and when he got there I looked at the temp gauge and again it was close to red (due to low coolant)

The plan is to take it to a mechanic to change the expansion tank.

Questions:

Is it bad to have an empty radiator in the hot summer for couple of days? (Car will be off all the time)

Is it bad to use non-bmw for testing the coolant system? (Will flush and put G BMW coolant)

Head gaskets are ok? No smoke came, no engine sound, and no oil and coolant mix visible so far.

Also, would it be ok to drive it less than 5 miles to the mechanic with the non bmw coolant? (with no overheating temp) Or should I tow?

Car info:
BMW 330xi 2004
Miles: 175K
Well taken car

Thanks,
 
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#6 ·
If it just barely got into the red, it's not good AT ALL. That being said I don't think that your engine is toast... I mean seriously, the red presumably means "Warning", so I wouldn't drop a new motor in because it might be toast. It would be worth it in my opinion to do a cooling refresh. I would definitely tow it if you need to take it to a shop.
 
#7 ·
Any BMW I've ever had, if it goes over halfway on the temp gauge, I shut it down IMMEDIATELY as it means something is really bad. If it got to the red, I'd assume something went boom. Drain the oil, do a compression test, blah blah blah. I hate to join the naysayers, but methinks this won't end well or cheaply.
 
#9 · (Edited)
The temp gauge is a dummy gauge. It's not a uniform increase in temperature from middle to red which means that it only reads cold -> normal -> new engine. Running it at even "close to red" is just as bad as red.

I hope it all goes well at the mechanic but I'll congratulate you on the new head gasket right now.

To answer your questions though:

Questions:

Is it bad to have an empty radiator in the hot summer for couple of days? (Car will be off all the time) No, that's fine as long as you never start or attempt to start the car.

Is it bad to use non-bmw for testing the coolant system? (Will flush and put G BMW coolant) It's fine to even use non-BMW coolant for extended periods of time providing it meets the same standards.

Head gaskets are ok? No smoke came, no engine sound, and no oil and coolant mix visible so far. I can't see sh1t over the internet so I'll leave that to your mechanic to decide. You'll need to drain and examine oil and do compression tests on the engine.

Also, would it be ok to drive it less than 5 miles to the mechanic with the non bmw coolant? (with no overheating temp) Or should I tow? If it's still leaking then tow. If you're not sure if it's leaking then tow. Based on what you have said so far, tow it. The brand of coolant is far less important than the quantity.
 
#10 ·
Speculation and doom sayers they'll be. Rapid loss of coolant with continued operation can make hot spots (bad) and create head gasket breaches when the head is pulling away from the block tearing out its studs in the process. The horror stories are out there and the common arm-chair diagnostic is trouble may be a brewin'?

Simple answer is a compression test before the cooling system rebuild. If all is well, treat yourself to a complete coolant system replacement with quality parts. You may have slid through the blowout and came out golden? It has happened before.
 
#13 · (Edited)
First: advise is a verb. Advice is the noun you are looking for.

Second, the replies in this thread are probably scarier than the reality.

Other than the problem you are facing (a busted expansion tank), the M54 engine is pretty strong. Unless you overheated the car to the point where you warped your head, my money says you wont face any lasting problems.

My experience tells me that warping the head takes more than a quick trip into the red zone on the coolant temp gauge. I've run my car at the track in 100+ weather when the car was coming close to the red over and over. I've also had two expansion tanks fail and had the red portion of the gauge illuminated for a moment before I turned the car off. I have had no issues with the head and zero lasting issues @ 175,000 miles on the odometer.

I agree you shouldn't use glue on a broken expansion tank, however. And I'd advise you to flush the system with distilled water before you refill with 50/50 blue bmw coolant and water. You'll want to remove the residue from the autoparts store coolant.
 
#14 ·
I believe the more likely damage than a head warp would be head gasket damage. You do know the stock parameters of the coolant gauge, right? The needle has a buffer in the middle that will cause it to stick in the dead center from 75 - 115 Celsius. Thats ****ing ridiculous. I reprogrammed my buffer to 90-100. If you ever hit red with a stock gague...well lets just say I wouldnt buy a car knowing its had a few trips to the red temp line. Dont know who would.
 
#16 ·
^ Actually not really. Other than the Germans, most automakers are still recommending ~7k mile oil changes and ~60k mile transmission fluid changes. None of the lifetime BS. My Acura has a maintenance calculator that factors in mileage, speed driven, how aggressively you drive, outside temp, and a bunch of other things to tell you when to change oil, fluids, and other things. I think the reason is that most of the people who buy these $50-60k cars don't want to keep them any longer than the model is new (ie, sold E46 when E90 came out, sold E90 when F30 came out, etc) and therefore their sales aren't affected by long term reliability and they therefore don't care. The Germans will fit as much tech and engine in a car as possible to keep it reliably running for the warranty period, after that it's just more money in their pocket. On the flip side, the people who buy Hondas and Toyotas are basing their business and sales on long term reliability. If you have a sh1tty and unreliable Honda, no one will buy it (example: newer Insight). If you have a sh1tty and unreliable BMW, it doesn't matter, everyone will buy it (example: bangle 7 series)
 
#17 ·
You should never drive an overheating BMW even if it's getting hot. You have to shut it down immediately and get it towed.

But at the same time don't panic, my girlfriend drove her 08 e90 to a gas station when she lost a belt and it was pegged in the red. It's been three years and it's still running fine. Not sure how she got away with that one.
 
#23 ·
A lot of current (and most older) Toyota motors are steel block with steel head. Steel has a higher heat capacity and are less prone to warping or other damage due to high temperatures. The newer Toyota motors are now aluminum which will be prone to the same issues. The difference is in the cooling system design (and other designs too :rofl:) which is much more robust on the Toyota than on the BMW.

BMW M54 is aluminum block and aluminum head, which is far more prone to heat issues than steel.

You can overheat a Ford V8 for days if you want and all you need to do is let it cool down before restarting, there probably won't be lasting issues doing this but they are all steel block/steel head motors.

I've heard these engines blow a head gasket if people don't charge the cooling system properly and it sits in the red too long. They're really sensitive to heat. It's possible if the car is moving at highway speed there is some airflow around the engine but that can't help much.
They are sensitive to heat because of aluminum construction. If it was steel there wouldn't be nearly as many issues.

Grey numbers show the stock temp gauge. If you leave the center, youre already dead. Regular operating temp is 86-98 C. Id know. Ultra Gauge
Operating temp and max temp are two different things but I get your point. The dummy gauge does cause problems.

So you guys are telling OP that he might as well not even try to fix it? These engines must not be nearly as good as I thought they were. Lol

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No one is saying that, people are saying to prepare for the worst. We all hope everything is fine.
 
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