High Coolant Temperature After Black Series Lifters + C63 MS Stage 1 Cam Phaser
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
High Coolant Temperature After Black Series Lifters + C63 MS Stage 1 Cam Phaser
Hi, I'm experiencing overheating issue after changing stock lifters for black series lifters and cam phaser plates for 63 Motorsports stage 1 upgraded plates w/ skeleton covers. I completed the initial startup process of bedding the new lifters with the old cams by revving to 1800-2300 rpm varying for a period of time. After 15 minutes of this I received coolant warning from the dash. I listened to idle and it had quieted sufficiently so turned off car. Coolant hoses from reservoir and to radiator were warm. Coolant appeared to have been circulating. I let the car cool overnight and checked coolant level. Level was low so topped up. Idled car for 20 minutes with coolant reservoir cap off and climate control heater running for 20 or so minutes to expel potential air from cooling system until I received the same coolant temperature warning. Coolant level remained at topped up/correct level. Radiator fan never kicked on but did previously when completing lifter bedding process. Please advise with anything that might help me figure this out. Thank you! I have no CEL or anything.
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
MBWorld Fanatic!
Joined: Jun 2009
Posts: 1,372
Likes: 412
2010 C63 AMG
Did not touch coolant since was not doing headbolts. Only thing I did to cooling system was temporarily hold hoses gently out of the way for access if anything. Based on what happened during the first start of the engine, I feel like the thermostat was working. The fluid appeared to have been shunted out of the reservoir and the hoses were hot which I thought would indicate that thermostat was hitting threshold to open. Is there a surefire way to confirm function or dysfunction of thermostat? I wouldn't be bothered to replace it since it's cheap and accessible from the top anyway. I'm nearing the replacement interval as well off the top of my head. Thanks.
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
Is OBD going to read anything that would tell me about the thermostat? I'd rather confirm it before removing it since I'll have to drop all coolant and remove the PS reservoir as well. Thanks again.
MBWorld Fanatic!
Joined: Dec 2005
Posts: 4,057
Likes: 341
From: NJ
2009 SL63 AMG
How long have you had the car before doing this recent work? If not something you just picked up, ever get a low coolant light before?
Also, if in the affected range, are the head bolts original?
The lifter / cam adjuster jobs have nothing to do with the cooling system, so it seems unusual for this to suddenly appear.
Are you sure there are no leaks from moving the hoses around?
Also, if in the affected range, are the head bolts original?
The lifter / cam adjuster jobs have nothing to do with the cooling system, so it seems unusual for this to suddenly appear.
Are you sure there are no leaks from moving the hoses around?
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
How long have you had the car before doing this recent work? If not something you just picked up, ever get a low coolant light before?
Also, if in the affected range, are the head bolts original?
The lifter / cam adjuster jobs have nothing to do with the cooling system, so it seems unusual for this to suddenly appear.
Are you sure there are no leaks from moving the hoses around?
Also, if in the affected range, are the head bolts original?
The lifter / cam adjuster jobs have nothing to do with the cooling system, so it seems unusual for this to suddenly appear.
Are you sure there are no leaks from moving the hoses around?
Trending Topics
MBWorld Fanatic!
Joined: Dec 2005
Posts: 4,057
Likes: 341
From: NJ
2009 SL63 AMG
Had the car a year, no low coolant lights, head bolts are the updated version confirmed via inspection while I was in the head (it's a 2014 car anyway). The only thing I interacted with beyond touching in the cooling system is the radiator fan because I needed my socket to clear the crank bolt, which worked again (radiator fan) after the first start procedure. I know that the systems I was working in don't really cross paths so I was extremely confused as to why any of this is happening. I'm going to run OBD when I get home from work to see if it tells me anything. There was a lot of suction at the oil cap this morning while the car was idling. I don't remember if that was normal or indicates anything. I haven't identified any leaks while looking over it with a flashlight this morning but I will keep looking.
Pressurizing the cooling system and checking for leaks would be a good step to take.
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
MBWorld Fanatic!
Joined: Jun 2009
Posts: 1,372
Likes: 412
2010 C63 AMG
For sure a pain to check the thermostat honestly just replace it for the $60 or whatever they are if you want to try it. They do fail randomly out of no where... although would be a weird coincidence that you just happen to have the car apart to. Nothing else seems to fit the bill though for why it would be overheating now. Unless you have a sensor gone and it's reading incorrectly but usually they read incorrectly as soon as you start the car as well. Did you check the temperature from the amg screen in the dash and or using the obd port through a diagnostic reader? Soemtimes they will read a different value and show the sensor has failed
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
For sure a pain to check the thermostat honestly just replace it for the $60 or whatever they are if you want to try it. They do fail randomly out of no where... although would be a weird coincidence that you just happen to have the car apart to. Nothing else seems to fit the bill though for why it would be overheating now. Unless you have a sensor gone and it's reading incorrectly but usually they read incorrectly as soon as you start the car as well. Did you check the temperature from the amg screen in the dash and or using the obd port through a diagnostic reader? Soemtimes they will read a different value and show the sensor has failed
Thread Starter
Newbie
Joined: Jan 2025
Posts: 6
Likes: 0
Thank you guys for taking the time to answer my questions I very much appreciate it.
MBWorld Fanatic!
Joined: Dec 2005
Posts: 4,057
Likes: 341
From: NJ
2009 SL63 AMG
Any special way to go about checking for leaks? The level in reservoir stayed the same throughout idle. I attempted to burp the system expecting the res level to drop for reason of expelling potential air but it never dropped. Visually I haven't found one. There is some residual oil/smoke on the driver side of the bay when running but the valve covers/cam adjuster covers dropped some oil onto the manifold when I was removing them so I can't tell if the liquid is new or old. When I turned the car off yesterday morning I just recalled hearing a sort of dripping sound from that side (around/inside/towards the wheel well it almost sounded like) and the audible texture sounded thinner/watery but again I was not able to see it anywhere.
Thank you guys for taking the time to answer my questions I very much appreciate it.
Thank you guys for taking the time to answer my questions I very much appreciate it.
Procedure from WIS attached. Basically, you remove the shields / trays, pressurize the system and start inspecting carefully for leaks.
Unfortunately, I'm not aware of a universal tester kit that works with the M156, which I learned the hard way in the middle of diagnosing something, prompting me to order the MB-specific tools.
If by chance you're local to NJ, happy to help you out.
Otherwise, your options are to find a compatible kit, order the MB one (part numbers in the attachment) or take it to an independent shop experienced with these platforms and have them check the system out.
A different route would be to add a special coolant dye to the system, put some good mileage on the car, and start exploring the engine bay / underside with a UV light.
