Can anyone tell me how to read coolant levels in our cars? I’ve been smelling coolant on occasion so I just wanted to check. I looked in the instruction manual and it’s hard to decipher what they’re measuring against. If that measurement is in the lid area, then I’m low (and it’s been like this since the day I drove it home). Can anyone check their coolant reservoir and see what level it is at? Is it the same? I’m not sure if the 450 and 53 would be any different with regards to the coolant tank. Thanks.

 

450 here mine was like yours when picked up from dealer last year. One day Warning light came on displaying low coolant. Took back to dealer they added more coolant to where yellow line is.
Low coolant warning hasn’t come back in a year.
Think mine smelled a little coolant in the beginning when purchased car.

 

Thanks. Can they not fill these properly? I don’t understand how they can get it wrong from the factory unless these things leak like a sieve.

Also, can anyone decipher the instruction manual coolant measurement?

 

I went and got some coolant 325.6. They also topped me off by just pouring pure coolant inside. They poured it to the same level they did for you Sig. However, doesn’t this require a mixture with distilled water, 50/50? It says on the jug that MB recommends a 50/50 mixture, I assume that is with water, correct?

 

I agree, the printed owners manual is pretty difficult to navigate. Too many countries, applications etc, so there's a lot of cross references and, unfortunately, some dead ends.

I have found it easier to use the search function in the car's display. Go to the home -> settings -> owners manual -> search, and start entering a word or phrase.
It'll give you several results, with linked cross references within the results, to other related topics.



Below is a picture of the coolant check. I scrolled down quite a ways, so these instructions are preceded by the coolant temperatures necessary to do an accurate check.


What you were looking at with your open hood photos, is the coolant reservoir, which is higher when it's hot and lower when it's cold.
The in-car manual also describes the markings on the reservoir. A link click away. Useful stuff in there.

 

Regarding your more recent post, the coolant mixtures are also specified in the owner's manual.

They may have topped you off with premixed coolant or a concentrate, but it really doesn't make much difference. A pint added to 20 quarts of coolant won't change the concentration very much.

 

I was doing some "fun" trail running with the 53 last week, and I had to make a hard stop on a very steep downhill stretch. I was lucky to stop in time!

I smelled coolant and a second later got a coolant warning, which has been retained in my messages. That evening when I got back in cell range, I also got an email from the Mercedes Me app.

When I got under the hood (cold), the cap felt a bit loose and there we're plenty of signs of coolant leakage around the cap.


I added 500 mL of distilled water, and brought the level up to the little white finger.

I suspect that it needs to be a little more full, but since this was a cold measurement I'll wait until I go hot cold hot cold a couple times. Then I'll recheck.

The reason I'll go through the cycles, is because if the coolant was low enough, it may have drawn air into the system, and I want it to burp itself out.
If that happens, then the coolant will be lower when I check it cold the next time.

I'm not sure what caused this. I haven't smelled coolant before, and since all the dust I was going through on my trail ride covered everything under the hood, this may be a fresh occurrence.
My emergency stop on a near 100% downhill grade is something I haven't done before, although I've pulled pulled over one and a half G's at the track

I'm due for my B service in a couple of weeks, so I'll do my "watchful waiting" until then.

I think I should have checked my cap for tightness sooner, but I'll inquire about a warranty replacement.

Check your caps, just in case.

 

Thanks for the the heads up @mikapen !