1999 540i might have had insulation eaten by rodents

[dianeseattle]

Hi, first, apologies if this thread has been posted before. I don't know how to search WITHIN a model type & can't search through thousands of posts by hand manually. Seriously, apologies. Please tell me if there's a way & I'll do it next time.

The subject of this post could also be something about my car overheating, though the temperature gauge inside says it's normal (hence, the mouse guess). But a few days ago, after being parked outside in the country, in a sort of carport which used to be a boat house, I went off on a trip & within 50 miles, my radiator was so hot, it not only bubbled over, but lost an inch of coolant within about 15 minutes of sitting with the motor off. I had topped it & the oil off before leaving. Prior to the five-week hiatus, the car ran like a champ, no trouble at all.

I was fortunate (well, maybe not) to be within 100 feet of a Ford dealership & a mechanic, so I went there. He had no idea about how to work on a BMW but offered a theory, that mice had eaten away at the wiring insulation & this had resulted, somehow, in this problem. He then showed me, to my complete astonishment, that there was a large bunch of the black insulation on the inside of the hood which had obviously been eaten away. Then he opened up a sort of plastic box fed by a large hose from the heating system (I guess) & among the small amount of debris were mouse droppings.

Still, I'm hoping it's a thermostat & that I might be able to replace it myself. I used to do VW tune-ups, carb & fuel pump rebuilds & one engine rebuild to put myself through college. The engine rebuild took six tries because my boyfriend & I kept on doing things wrong, like not getting the cylinders machined or losing some sort of ring clamp (can't remember it now) that went rattling around in the head, etc. etc. So I know how to do things right, & I know how to do things wrong.

I hadn't intended ever to do my own work on modern vehicles, which are so much more difficult than the old cars from 1930 through the mid-1970s, which were obvious & easy to work on. I have a BMW mechanic in town & have brought my used 1999 540i to him every month to do one thing at a time to the car to make it better or keep it maintained.

But then this happened. I ended up having it towed home for $300 & renting a car for $100, which has exhausted my repair budget for the month, by far. I live on a small fixed income temporarily while I recover from a disability.

If anyone has any idea or has encountered this, please let me know. I'm so happy to listen to anyone's experience & advice about how to approach this. I'm not going to drive the car (even though I could, until it got too hot & I had to park it & let it cool off) until I fix the problem because I love my car & want it to run fine for a long time.

Thank you.

diane

[macky55e34lover]

causes of overheating - busted clutch fan, busted thermostat,worn down hoses, radiator leak sometimes even the reservoir, dead aux. fan, worn cylinder head gasket, in extreme cases - small tiny microscopic holes on the engine block makes it lose water hence the overheat

if there is indeed evidence that the wiring is damaged bec. of the rodent- repair it then observe the reliability of the gauge, if it still gets too hot then you have to check the things i mentioned first

[dianeseattle]

thanks very much. I'm doing most of those things, but you directed me to a few more. I appreciate it.

diane