GLC63s, GLC63, GLC43 AMG SUV and Coupe (X253, C253) 2015 - Present

Overheating glc63?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Oct 17, 2021 | 02:53 PM
  #1  
DG2020's Avatar
Thread Starter
Newbie
 
Joined: Aug 2020
Posts: 11
Likes: 0
GLC63 2020
Overheating glc63?

I've noticed the fans coming on more and more frequently, but the engine/box temps always stay within good ranges. Weather in nyc is cooling down (50-70) and this is from just putting around the neighborhood so nothing really over 3k rpm or over 30mph.

Putting my hand on the radiators at the front of the car they all feel fine, apart from the unit at the very front that's mounted horizontally - anyone know what that does? It's almost too hot to touch.
Reply
Old Oct 17, 2021 | 05:32 PM
  #2  
superswiss's Avatar
Out Of Control!!
5 Year Member
Community Influencer
Loved
Community Favorite
 
Joined: Nov 2018
Posts: 11,432
Likes: 5,343
From: San Francisco Bay Area
2019 C63CS
Not sure which specific unit you are referring to, but there are separate radiators for the coolant, engine oil and transmission. The main reason for the fans to come on and run for up to 10 minutes after shutting off the car is the Hot-V turbo setup. It gets very hot in there, so the fans run to cool the turbos avoid cooking the oil. This is a very common phenomenon on all Hot-V engines. There are air channels to blow air over the turbos when the car is stationary or stopped. It doesn't take much for the fans to run for a bit after stopping the car. A short acceleration burst with the turbos making boost and then stopping shortly after may be all it takes. These engines do get hot. My garage feels like a sauna for hours, and I always wait for the fans to stop before closing the garage door to let it blow some of the heat out of the garage.
Reply
Old Oct 18, 2021 | 04:01 PM
  #3  
larrysing's Avatar
Junior Member
 
Joined: Mar 2021
Posts: 64
Likes: 17
AMG GLC63
Originally Posted by DG2020
I've noticed the fans coming on more and more frequently, but the engine/box temps always stay within good ranges. Weather in nyc is cooling down (50-70) and this is from just putting around the neighborhood so nothing really over 3k rpm or over 30mph. Putting my hand on the radiators at the front of the car they all feel fine, apart from the unit at the very front that's mounted horizontally - anyone know what that does? It's almost too hot to touch.
This is caused in part by the fact that some of the Mercedes M177 cooling system pumps DO NOT TURN ON until the system reaches 50 Celcius. Per Blackboost:

"Believe it or not, Mercedes does not even turn on the water pumps for the factory air to water intercooler system until temperatures have exceeded 50*C!!!"

So in colder weather, the cooling pumps might not even turn on, so the "post-drive fans" have to do the job. What you see is normal, unfortunately!
Reply
Old Oct 18, 2021 | 09:46 PM
  #4  
DG2020's Avatar
Thread Starter
Newbie
 
Joined: Aug 2020
Posts: 11
Likes: 0
GLC63 2020
Have booked it in for a check. Have noticed the fans come on after shutdown, and that makes sense, but am noticing them coming on quiet hard early on - first 5min of driving lets say, and the horizontal cooler is too hot to touch. Did make me think one of the pumps is dead/blocked etc, then again, may not just be being turned on. Even after driving on the highway for 5min the horizontal cooler is super hot, and having touched it many times in the past I've never known it to be more than warm, even after a heavy hit.

Sometimes I think it would have been easier to get a rav4
Reply
Old Oct 19, 2021 | 10:27 AM
  #5  
ParadigmDawg's Avatar
Super Member
 
Joined: Aug 2019
Posts: 881
Likes: 300
AMG GLC 63s Coupe
Originally Posted by DG2020

Sometimes I think it would have been easier to get a rav4
LOL.....or stop overthinking it and just go drive the AMG like it is intended to be driven...."HARD"....
Reply
Old Oct 20, 2021 | 05:33 PM
  #6  
larrysing's Avatar
Junior Member
 
Joined: Mar 2021
Posts: 64
Likes: 17
AMG GLC63
These engines run hot.
I've just started opening my hood every time I get home to let it cool.
I'm waiting on Modalworks to get me a 3-piece unit - they are testing it right now, or very shortly.

I WILL beat the heat!!!

Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 12:36 PM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE