Coolant temperature range for 1985 380 SL stand

[gabriel_parkeru]

Salutations Everyone,

Please tell me that my car is behaving within the legal parameters.

The temperature gauge goes up to just over 100 degrees when I turn the key to start the engine, then drops to just over 80 degrees and remains there.

I want to make sure this is normal because I know it's bad to overheat the aluminium engine.

[kasper_youngq]

Maybe the thermostat is stuck. The typical temperature range for it to begin opening is 82–86 C, and it should reach full openness at 100 C.

In my vehicle, the needle will rise to about 90 degrees (halfway between 80 and 100) before dipping to slightly more than 80.

Will your auxiliary cooling fan activate when the temperature reaches 100 degrees?

[emmatorrescj]

Like other people I've read about, mine does the same thing. There is a slight stickyness to the thermostat. My choice of Beck\Arnley when I replaced mine approximately 6 years ago may have been a mistake now that I look back, but mine didn't start sticking until about 4 years ago. Though unsettling, it was only momentary. Damaging? Unless it continues indefinitely, it is highly unlikely. I'm interested in hearing other people's perspectives. It's a pain to swap out, and because I'm still young and have a lot of money in the car, I'm not sure I want to treat it like a real problem. However, I will choose a solution that fixes it when I'm bored (which isn't going to happen very soon!).

[kasper_youngq]

Something I discovered in my vehicle is that the pin that seals the hole in the thermostat was snipped off at some point in the past. Just so you know, this is the original thermostat. The thermostat may have become stuck because of it, or it may have been believed that keeping this bypass open would make the car run cooler. It may have been hot in the past, since it also has a "140" label on the tank cap.

[emmatorrescj]

I saw a few different brands of thermostats that, by design, didn't have the pushrod thingy, but I stuck with the one I was already familiar with since I'd never heard of the others.The temptation to remove it is understandable. I believe its purpose is to enhance the efficiency of the warm-up. The hole prevents air from collecting; when water is present, the rod is forced shut. This is just nitpicking, in my opinion.

[kasper_youngq]

When the thermostat is completely closed, a small amount of water can still flow through the engine through the hole that the rod seals. With the opening of the thermostat, the pin seals it.

Because some of the heated water will return to the water pump inlet instead of the radiator, leaving it open actually decreases cooling. However, I never experienced any problems with my car's cooling system.

[arjun_wilsonu]

I find it intriguing that yours rapidly reaches 100 and then decreases. When I turn on my engine, mine simply starts off low and gradually goes up. When it's hot, it runs at approximately 90 RPM. Perhaps my thermostat is broken? She still runs as fast as before.