Originally Posted by Kenek
Well that begs the question(s)- does having the engine get warm, for a very brief period due to a failed fan, constitute a potentially damaged engine? Is there any type of built-in feature that would shut the engine down if a too-hot condition occurred to protect it? I have to assume that with the level of engineering at Mercedes/AMG they take into account certain negative situations and engineer these engines accordingly. Am I wrong?
All cars can be ran too hot and do major damage. I had a repair shop for 10 plus years and saw it ALL the time. It was in South FL and I worked on MBs, BMWs, etc. all the time---that's why I bought a SRT6. People would say "I'll make it to the next exit" or "it was dark"---then they would come to me for a new motor. I put in many motors due to driver error. The 8.5 qts of oil does help but do not count on that to save your a$$. Three or so extra quarts can not stop aluminum from cracking, melting, or warping.
You said "warm for a very brief period", but your first post you said "pegged"---Well, it was hot enough--long enough that the computer shut down the A/C---that was your warning. The car will not cut "off" because you could be on the highway or in a turn, and you would loose power steering, power brakes, etc. Engineers "assume" that the driver will watch the gauges/lights that they put in the cars, and like I said, the cutting of the A/C was a MAJOR warning that the car was in an overheating situation. Do not "assume" that the car will save itself. The DRIVER is the one responsible not the engineer.
It could be ok---but here's my question again---How long has this been going on? The dealer did not catch it which worries me---it should scare the hell out of you. Real hot then cool down---real hot then cool down. That metal will be fatigued if that has been going on for a while. Just take a coat hanger and bend it back and forth---once or twice ok, but do it a few more times, and it will break.
My professional advice which comes from a master tech with a L1 cert---get out of the deal---too many good cars out there. I just bought mine with 917 miles for $19,655. It was at the very top of the range, but like I said, I worked on these ALL the time, and I did not want to to have any questions about the car. This one has a lot of questions---How many times has this happened---is my first one!!!! If you really want to take a chance---MAKE them put a powertrain warranty on for at least a year, and tell them it is the "stupid tax" for not catching the problem. If you will not, I will for you---really I will. They had a car on their lot for sale that would overheat on test drives for crying out loud---that is stupid. They did not check this car out very well did they?