[Warp Ten]

Originally Posted by Zap-xpilot

UPDATE:

So I took the car to the dealership and they filled almost a full litre of coolant. There was the usual talk of an air bubble trapped, which I call BS. After all, I drove the car around Germany, France and Spain this summer in searing heat, often at V-max - if that doesn't percolate the coolant inside I don't know what will.

The service guy (who is quite knowledgable, I'll give him that) said that it is not uncommon for 540s to "drink" coolant.

On top of everything else I believe he over-filled the coolant chamber - I don't know if you can see it in the pic, but the top of the MAX-level is barely visible.


Is it dangerous to over-fill the coolant reservoirs? It is freezing in Sweden at the moment, so the risk of overheating is limited, but I'm kinda nervous.

Where does the cooling liquid go? I've checked in my garage and there is no coolant spill under the car?

Engines don't "drink" coolant unless they are broken. If one is not seeing any coolant leaking onto the floor, and no leaks are suspected during driving, then the only way for an engine to "drink" coolant is through the combustion process--at least as far as I have ever seen. I don't know much about G30 at this point but I have seen older cars that have had coolant leak past gaskets or even casting cracks into the combustion chambers. The result is normally white exhaust smoke (as opposed to black (rich mixture) or grey (oil). If it is only a small amount then it may not be noticed, especially with catalytic converters burning up most everything. Sometimes you can get a slight smell of antifreeze--a sort of sickly sweet smell--from the exhaust even without white smoke. None of this, of course,
may apply to the much improved but more complicated cars of today.

Not really directly related, but many moons ago I had a 1980 530i that I left at my dealer for a regular service. When I came to pick it up it was parked out on the street in front of the dealer. After I paid for it and started it, I got a big plume of white smoke out the exhaust--something that apparently the technicians completely missed when working on it or parking it. Told them it wasn't like this when I brought it in. Had a nasty back and forth with dealership owner. They said it had a cracked head, was not covered under warranty and they wanted to make me pay $2,000 to fix it;later compromised to pay for half of it. I did some research (before internet and forums) and discovered that it was a known design defect and that BMW was indeed paying for repairs. The dealer had tried to double dip on me. They eventually replaced the head without cost to me. Apparently the defect was a fine crack that developed in the casting. THe dealer also had been rapped on the knuckles by the state for odometer rollbacks back in that era. Ironically, about 35 years later in my early retirement I went to work for the same dealer who had moved to a different location. Sold BMWs and MINIs there for seven years and they now have a sterling reputation which I can vouch for.--Bob