Exhaust Rattle C63S coupe.
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C63s Estate
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From: Queens NYC
PFL C63s EC Stage II
Had the same thing going on, I had to pull the valve motor out heat the spring and make it so it gives out more pressure to the butterfly valve. PITA to install it back with the additional pressure. Never heard a single cling after.
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⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
What did you heat the spring with? Did you "pull" the spring outwards while it was heated to expand it more so it's a tighter fit when you install everything again?
This is mine at the moment.
Last edited by Jimmy_c63s; Aug 24, 2020 at 08:57 AM.
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From: Queens NYC
PFL C63s EC Stage II
I used a regular propane torch. No you don't pull the spring outward you have to somehow heat it and twist it so it gives out more "spinning force". I forgot which way it was. Get under the car and play around with the butterfly valve to see in which position its closed and tension the spring so it shuts the valve more securely so it shuts it more effectively eliminating the rattle. Do not go crazy with over tensioning it as it will be hard to install. Basically you need to get a feel of it. Apply a dab of WD- 40 specialist in the middle of the spring before re-installing. Sorry its kind of hard to explain specialy with English not being my first language.
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From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
I used a regular propane torch. No you don't pull the spring outward you have to somehow heat it and twist it so it gives out more "spinning force". I forgot which way it was. Get under the car and play around with the butterfly valve to see in which position its closed and tension the spring so it shuts the valve more securely so it shuts it more effectively eliminating the rattle. Do not go crazy with over tensioning it as it will be hard to install. Basically you need to get a feel of it. Apply a dab of WD- 40 specialist in the middle of the spring before re-installing. Sorry its kind of hard to explain specialy with English not being my first language.
When you heated the top of the spring, did you need to heat it until it was red hot in order for it to be deformed? I just don't want to overdo the heating and completely destroy it 😅
Last edited by Jimmy_c63s; Aug 24, 2020 at 11:59 AM.
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From: Queens NYC
PFL C63s EC Stage II
Thanks for explaining as best as you can, I get what you're saying now. You heated just the top part of the spring (where it sits on the actual metal flap spindle) and slightly bent it to an angle so that it sits really hard into the exhaust flap spindle 👍
When you heated the top of the spring, did you need to heat it until it was red hot in order for it to be deformed? I just don't want to overdo the heating and completely destroy it 😅
When you heated the top of the spring, did you need to heat it until it was red hot in order for it to be deformed? I just don't want to overdo the heating and completely destroy it 😅
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⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
Just pull the spring off the motor assembly and secure one end of it somewhere heat it and twist it, take a picture of it how it looked originally. The middle notch thing is what you twist. A little bit is enough like I've said you have to feel it. I had my car on a pair of jacks when i did this and before i got it just right i had to get under and back out a couple of times.
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From: Queens NYC
PFL C63s EC Stage II
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2019 AMG GT R
The car loses its growl if you keep the valve open.
i know this because initially I thought keeping the valve open would equal max sound but like you said the car lost its growl.
welded a metal disc in between after and voila all the growl was back without the annoying rattle.
This H valve is just too faulty. Even the one I got with the AWE Track exhaust started rattling. Could have ordered a new pipe under warranty but wanted a more permanent solution so fixed it the same way
Last edited by untamedd; Aug 24, 2020 at 12:37 PM.
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From: Queens NYC
PFL C63s EC Stage II
wrong.
The car loses its growl if you keep the valve open.
i know this because initially I thought keeping the valve open would equal max sound but like you said the car lost its growl.
welded a metal disc in between after and voila all the growl was back without the annoying rattle.
The car loses its growl if you keep the valve open.
i know this because initially I thought keeping the valve open would equal max sound but like you said the car lost its growl.
welded a metal disc in between after and voila all the growl was back without the annoying rattle.
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2019 AMG GT R
honestly i dont know the technicalities since im just speaking from the experiments I did from which i can conclude:
The H valve actually closes under load to change the tone of the sound giving it that growl (confirmed via the fact that a welded closed H valve sounded much more rowdy than a fully open one)
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C 63 S
Screeching when decelerating open valves
Hello, I've been with my C 63S for almost two months now and I just noticed that when accelerating with the exhaust valves open the car makes a squeak, with the valves closed it does not. To be exact you can hear the screech when decelerating.
Does this happen to everyone?
Thank you.
Does this happen to everyone?
Thank you.
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From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
Hello, I've been with my C 63S for almost two months now and I just noticed that when accelerating with the exhaust valves open the car makes a squeak, with the valves closed it does not. To be exact you can hear the screech when decelerating.
Does this happen to everyone?
Thank you.
Does this happen to everyone?
Thank you.
Mods please merge topics.
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Joined: Sep 2016
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From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,718
Likes: 608
From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,718
Likes: 608
From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
After over a year with this rattle i've finally decided to be done with it and get it welded shut.
I've got my secondaries removed but wanted to ask you:
• Did welding the H pipe "closed" cause any drone with a secondary cat delete?
• Does it cause any difference in sound in full comfort (quiet) mode?
• And did it make cold start any louder (I don't want that).
Thanks mate.
Last edited by Jimmy_c63s; Nov 28, 2020 at 01:01 PM.
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2019 AMG GT R
Should've just listened to you from the start! 😤
After over a year with this rattle i've finally decided to be done with it and get it welded shut.
I've got my secondaries removed but wanted to ask you:
• Did welding the H pipe "closed" cause any drone with a secondary cat delete?
• Does it cause any difference in sound in full comfort (quiet) mode?
• And did it make cold start any louder (I don't want that).
Thanks mate.
After over a year with this rattle i've finally decided to be done with it and get it welded shut.
I've got my secondaries removed but wanted to ask you:
• Did welding the H pipe "closed" cause any drone with a secondary cat delete?
• Does it cause any difference in sound in full comfort (quiet) mode?
• And did it make cold start any louder (I don't want that).
Thanks mate.
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,718
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From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
How about in full comfort mode with the exhaust flaps set on quiet? With the the H flap permanently welded shut, did it sound normal to you in full quiet mode? Only asking cos even though I have secondaries out, I always use comfort mode with exhaust on quiet when driving around my elderly mother to her appointments 😆
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C205 c63
Mine has started making this noise on shutdown as well now. Wonder if it's a symptom of the same issue? 
https://youtu.be/6_Yhp1Mbbe4
https://youtu.be/6_Yhp1Mbbe4
