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Old 10-19-2010, 05:52 PM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
1. Do not drive the car and do not pour cold water into an overheated engine - let it cool down for 30 minutes first before adding water.

2. Are you losing coolant?

3. Are there any leaks from hoses that you can see?

4. Is there water or too much water vapour coming out of your tailpipe? This can be tested by holding a cold surface to the tailpipe with the car running at idle....a wallet or mirror will do. Depending on where you live (and if it just rained), some water vapour is normal, but if you're getting more than normal water vapour, then yes, your HG (head gasket) or cylinder head at worst may have big problems.

This can often be corroborated by checking under your oil cap, looking into your crankcase and pulling out the dipstick to see if water has mixed with your engine oil.

5. It may be a case of simply not bleeding the radiator properly, which may be especially true since you've just flushed the radiator (btw, please recheck to see that all clips and hoses are back on tight). Bleeding has to be done 4 times to be truly effective. (With the cabin heater set to high and the blower set to #4) The first bleeding would be when coolant is added to the brim and overflowing through the bleed screw with the engine off. Then the engine is started and coolant is added once again after the car *has reached operating temperature* (have someone help you monitor this since there's a risk of overheating here). Then finally, the entire procedure has to be repeated once again when the engine is cold...preferably left overnight. This will eliminate pretty much all of the bubbles you could have had.

6. If you did not bleed your radiator in this way, please do so again. Afterwards, start the car, leave it at idle and watch the thermometer. Watch this for 30 minutes to check if everything is normal. Listen to music, have some beer and dinner, talk to someone on the phone, but do not take your eyes off the needle.

7. If there's no overheating, watch the gauge very often over the next 7 days. If there's no overheating, then you're totally out of the woods with no permanent damage to your system.

8. Check to see if your fan clutch is in good shape. Please search these forums or google to determine the best method of checking this.

9. Check your fusebox to see if anything is blown. Do you have an auxiliary cooling fan? If you do, your aux fan's fuse could have blown.

10. If you have an aux fan, it may not be working. Please check that.

11. You may have a busted radiator. Try to see if there are any leaks but many leaks only become visible at high pressure so it may be difficult to tell. But look at every joint of the radiator closely and under very good lighting, you may spot something. If you have any small leaks, it can be fixed with high temperature silicone window seal...I've done this on my car and its held up without problems for the past 3 months.

12. If you've not changed your radiator tank cap and bleed screw recently, please do so immediately. These two items could be sources of premature coolant loss and they are really cheap to replace.

13. There is a possibility that the prior overheating events has caused permanent damage to either your HG or your cylinder head. If so, this damage will be there even if you find and fix the original problem. You need to monitor your car carefully for some weeks after you find the original problem.

14. If you feel you've found the problem, please do #6 and #7 listed above to check.

15. Please put 3-4 gallons of water in your trunk right away. A can of very cheap coolant from the gas station wouldn't hurt either. This needs to be there for the next few weeks as a precautionary rescue kit. It can be discarded after you've determined that everything is cool , permanently.

16. Good visual observation and a clear, calm mind are the keys to finding and fixing this and pretty much any other non-obvious problems with our E34.

16. Good luck and do keep us posted about your progress.

Last edited by robertobaggio20; 10-19-2010 at 05:56 PM.
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