I just recently got an oil change and coolant top off and since that oil change, my 1989 560SEL has been running a bit hot. Originally, I believe that the mechanic overfilled the coolant container since I made sure it was topped off, with the proper air gap, the night before. So the day after that oil change, the car ran hot and extra coolant basically leaked out. The car ran perfectly for the next couple of days, then recently it started running hot again. In the morning, when I first drive it, it is fine then within maybe around ten minutes within driving, the gauge slowly climbs to about 80 degrees celcius and then shoots up into the red within a minute or so. The funny thing is, that on the highway at speeds over 60 MPH, it drops to the normal temperature range, even when it was close to redlining (or already there.) It only overheats on daily around the town driving. (I have a BMW and this car never even came close to overheating.) When it overheats and I take a look under the hood, there is no leaks, no coolant leak, the collant tank is full, hot.
I my hypothesis is that maybe could it be a kink in the hose that leads to the block, or does this mean, that the mixture is wrong, or something wrong with a valve (The name of this valve is on the tip of my tongue.). Or does this just mean it's time for a coolant change?
Unfortunately, there is not a mechanic around here that would even take a look at it within 100 miles of here. I think the problem is a simple fix, but my time is short and since I belong to this forum and all, I'm always open to tips and thought without getting the run around. Thanks.

 

Ironically, the problem have been solved just by a flush and fefill. As the coolant was draining, I noticed the typical blue/green coolant. I refilled it with the official Mercedes (yellow) Anticorrosion anitfreeze and the car stopped over heating. Is there a difference in the chemical build of the regular blue/green coolant and yellow coolant besides the anticorrsion?

 

There may have been a bubble in the cooling system before you flushed and refilled it.

 

Could've been. How does a bubble get in there in the first place?

 

Rushing the job.

 

Well that's what I get for going to a quick lube place.