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I was driving to work this morning and my wife called me to tell me there was red fluid on the garage floor where I park. Ugh. I hadn't actually driven it in about 2 days and she said it looked like a few ounces. Can't think of anything else that's red, so guessing it's trans although I had no shifting issues driving to work this morning.
You guys hear of trans leaks on these before? If I need to add some before getting it to the dealer, what type trans fluid and where do I fill it? Is in the back near the firewall? Basically fill it through the dipstick tube? I've never had to add trans fluid before on any of my AMG's. Kinda strange.
I just went down to my work parking lot and found a small puddle near the right front end almost directly under the passenger side heat exchanger. Fluid was kind of reddish yellow. Does the dealer use red coolant? is this the color of the inter-cooler fluid? If so, what are my risks here, and where would I add more? From memory, I recall a little reservoir under the airboxes. Would this be it?
From 2015 and on, mercedes switched to red coolant fluid....
u might be leaking from coolant reservior for the engine since it sits on that side, check the level and add as needed.. but you. Have to pinpoint the leak.
I have red coolant in both primary reservoir and IC res. Could be a rock damage to the heat exchanger which is common or a fitting. Mines a 2016, i dont remember 100% but i think the right side aux heat-exchanger is For the IC on m157.
It's the coolant reservoir. There is obvious residue underneath it. Still not very low though. Looks like when they put the new motor in they messed up a fitting or something. So whew! Not a big deal.
Vrod - curious if your coolant reservoir looks like mine here with this slight leak? Glad you figured out your situation was coolant and not trans leak.
For me, It’s literally just a few drops that has taken 6 months to accumulate at what you see in the photo. MB Chicago dealership tells me this is slight leak is normal and they did a pressure test and said everything Is fine but couldn’t address why there is a slight leak. I asked if other E63S show this pattern as well and they said NO but still wouldn’t replace the leaking reservoir which is still under warranty for me. I’m going to the other MB dealer next month for 30k service and will bring this up which I assume they will fix since they have been awesome as a dealer.
I see alot of overfilled coolant tanks, leads to venting and spilling of coolant that runs down the tank, which may make it seem like it is leaking.. always good to clean it up and re check because of this.
So here are a couple of pics of the issue. I really doubt it was overfilled. I had been getting a dash warning of low coolant (I posted in a different thread a few weeks ago). I only added about 3 ounces and the warning went away. When I was getting the low coolant warning I had thought I had a faulty gaskets on the reservoir cap due to residue around its edges. The stuff below the reservoir in the pics is fairly new. I would have noticed as I keep my engine bay pristine. Which now means cleanup in this area thanks to this. Ugh.
Jvakos, As you can see my situation looks a lot worse than yours.
Thanks again to all. Just posting these pics for those folks that are curious. Notice on the top picture, the spray onto the intake tube while in the bottom picture there appears to be a worse issue. I may have an issue with the cap and fittings underneath. I have an appt with dealer on the 24th. I suspect they will replace it and clean things up. They take pretty good care of me fortunately.
Pop the hood next time after a drive where the engine has been brought up to temp. I had a pinhole leak in the side of the reservoir that was only visible after driving and pressure built up. It would shoot a stream of coolant exactly in the areas shown in your pictures.
I wonder if our cars have pressure release valve mechanisms built into the cap itself.... ?
As the pressure in the coolant system increases, the mechanism is put under load as such, but if this mechanism has failed or is failing it will allow a discharge of coolant. Effectively it will not hold pressure.
I will check my cap tomorrow, but if you remove the cap and shake it, it should rattle, if all is good (that's the mechanism). If there is no rattle then it has failed.
For safety, a failing / failed one, should not hold pressure as the consequences for it to fail in the stuck closed position, essentially will over pressurise the system.
Just a thought....I have very little experience with an M157.
09-10-2019, 11:13 AM
