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Great job! Please keep us posted with updates at your convenience.
My 2013 C250 with 28k miles does not have the engine noise mentioned in this thread. But lately, the brake pedal is stiffed up in the morning. Symptoms correlate to a leak in the vacuum line. Not sure if the vacuum line has a one-way check valve but replacing the brake vacuum pump with a non-OEM fixed the problem.
My searches for a brake vacuum pump rebuild kit brought me here. Anyone?
Hello, I have been experiencing a problem with the brake pedal hardening before starting the car lately, as you mentioned. I suspect the issue is related to the vacuum line. When the engine is turned off, there is a leak somewhere, causing a loss of Westinhouse vacuum and resulting in the hardening of the brake. Did replacing the brake vacuum pump completely solve your issue? If so, I might consider replacing the pump directly without inspecting the vacuum line.
Hello, I have been experiencing a problem with the brake pedal hardening before starting the car lately, as you mentioned. I suspect the issue is related to the vacuum line. When the engine is turned off, there is a leak somewhere, causing a loss of Westinhouse vacuum and resulting in the hardening of the brake. Did replacing the brake vacuum pump completely solve your issue? If so, I might consider replacing the pump directly without inspecting the vacuum line.
The issue is probably the brake booster rather than the vacuum pump. The vacuum is leaking out while the car is parked, resulting in a hard pedal prior to starting the engine. When the engine starts, the vacuum pump runs and reinstates the vacuum and the normal pedal feel.
The issue is probably the brake booster rather than the vacuum pump. The vacuum is leaking out while the car is parked, resulting in a hard pedal prior to starting the engine. When the engine starts, the vacuum pump runs and reinstates the vacuum and the normal pedal feel.
Yes, I absolutely agree with what you said, another possibility could be Westinghouse. Of course, since it is more expensive than the vacuum pump, I might try the vacuum pump replacement first. Currently, in my country, the original Mercedes pump is 241.24 euros, and the original Mercedes brake booster is 810.05 euros.
Yes, I absolutely agree with what you said, another possibility could be Westinghouse. Of course, since it is more expensive than the vacuum pump, I might try the vacuum pump replacement first. Currently, in my country, the original Mercedes pump is 241.24 euros, and the original Mercedes brake booster is 810.05 euros.
Ouch! That's expensive. I chose the ATE brake booster for my vehicle. Much less expensive, and the booster is made by ATE for Mercedes. The part number for my 2013 C205 is ATE-300261. I would check with whatever parts supplier you have in your country for the actual part for your year/model.
Hello, I have been experiencing a problem with the brake pedal hardening before starting the car lately, as you mentioned. I suspect the issue is related to the vacuum line. When the engine is turned off, there is a leak somewhere, causing a loss of Westinhouse vacuum and resulting in the hardening of the brake. Did replacing the brake vacuum pump completely solve your issue? If so, I might consider replacing the pump directly without inspecting the vacuum line.
In my case, the brake pedal was stiffed up, high and hard after a night sitting in the garage. The brake is fine after starting the engine and when driving around with multiple short trips. I searched within this forum and according to other members, replacing the brake vacuum pump fixed it for them.
I bought an inexpensive and perhaps a Chinese knock-off brake vacuum pump and YES, my brake is fixed. Crossing my fingers that it lasts longer than expected.
I am not sure if our car has a one-way check valve. But I'll leave that for other members to confirm.
P.S. I opened, cleaned and sealed the original vacuum pump with a gasket maker after watching the YT video on how to restore it. Might be worth saving it as a spare!
We had a 2013 Mercedes C250 with the M271 engine towed in to the shop with broken timing chain. After replacement of timing chain, both cam gears, tensioner and all the bent valves in the cylinder head, replaced the balance shaft tensioner also ( had the plug that was mentioned blown out as well).
After all that work upon test drive the engine was rattling like the the original posters video. After checking oil pressure the oil pressure was at or above Mercedes specification in every RPM range with the oil filter cap pressure tested adapter. After close inspection of the original oil filter cap that was on the vehicle I noticed the bottom part towards the middle above the 2 lower o-rings was broken see photo below of the cap. Because of the broken part the lower part of the oil filter cup where the 2 o rings sit never seal oil pressure inside the engine and cause a oil pressure loss. With any oil pressure loss the exhaust camshaft adjuster will make rattling noise and the loudest point is in the back of the engine at the brake vacuum pump. If any of you guys have this issue with rattling MAKE SURE TO CHECK YOUR OIL FILTER CAP VERY CLOSELY AND REPLACE IF ANY MOVEMENT AT THE BOTTOM OF THE FILTER CUP O-RINGS.
This is where it breaks and causing a loss of oil pressure This is how it is supposed to look like when NOT broken
We had a 2013 Mercedes C250 with the M271 engine towed in to the shop with broken timing chain. After replacement of timing chain, both cam gears, tensioner and all the bent valves in the cylinder head, replaced the balance shaft tensioner also ( had the plug that was mentioned blown out as well).
After all that work upon test drive the engine was rattling like the the original posters video. After checking oil pressure the oil pressure was at or above Mercedes specification in every RPM range with the oil filter cap pressure tested adapter. After close inspection of the original oil filter cap that was on the vehicle I noticed the bottom part towards the middle above the 2 lower o-rings was broken see photo below of the cap. Because of the broken part the lower part of the oil filter cup where the 2 o rings sit never seal oil pressure inside the engine and cause a oil pressure loss. With any oil pressure loss the exhaust camshaft adjuster will make rattling noise and the loudest point is in the back of the engine at the brake vacuum pump. If any of you guys have this issue with rattling MAKE SURE TO CHECK YOUR OIL FILTER CAP VERY CLOSELY AND REPLACE IF ANY MOVEMENT AT THE BOTTOM OF THE FILTER CUP O-RINGS.
This is where it breaks and causing a loss of oil pressure This is how it is supposed to look like when NOT broken
Thanks for the suggestion - howd your timing chain break?
I do not know why the chain broke but I would suspect because of low oil pressure. The chain tensioners are oil fed and same as the cam adjusters. If they do not have enough oil then the chain will slap inside the engine and eventually break.
We had a 2013 Mercedes C250 with the M271 engine towed in to the shop with broken timing chain. After replacement of timing chain, both cam gears, tensioner and all the bent valves in the cylinder head, replaced the balance shaft tensioner also ( had the plug that was mentioned blown out as well).
After all that work upon test drive the engine was rattling like the the original posters video. After checking oil pressure the oil pressure was at or above Mercedes specification in every RPM range with the oil filter cap pressure tested adapter. After close inspection of the original oil filter cap that was on the vehicle I noticed the bottom part towards the middle above the 2 lower o-rings was broken see photo below of the cap. Because of the broken part the lower part of the oil filter cup where the 2 o rings sit never seal oil pressure inside the engine and cause a oil pressure loss. With any oil pressure loss the exhaust camshaft adjuster will make rattling noise and the loudest point is in the back of the engine at the brake vacuum pump. If any of you guys have this issue with rattling MAKE SURE TO CHECK YOUR OIL FILTER CAP VERY CLOSELY AND REPLACE IF ANY MOVEMENT AT THE BOTTOM OF THE FILTER CUP O-RINGS.
This is where it breaks and causing a loss of oil pressure This is how it is supposed to look like when NOT broken
This information is worth remembering. That part tends to break in many cars, not only in Mercedes-Benz. I will check this on my car because I am now proudly part of the knocking-engine team
So here's my story: I changed the oil after 7,000 km, deciding to use 5W40 229.3 again. I used a Hengst oil filter. After 2-3 thousand km, the engine noise became the same as what everyone interested in this topic has described. It happens only after a long stop in Drive (at 650 rpm) and keeps knocking only if I do NOT reach 2,000 rpm. After reaching 2,000 rpm or more, it is silent until I stop for a moment in Drive at idle (650 rpm) and go again.
After reading some WIS and learning what it could be, I figured out that the noise had to come from both camshaft adjusters.
Long story short: if the noise occurs, readings from the exhaust camshaft fluctuate by 10 degrees. If there is no noise, readings are stable on both camshafts. That's why many of you probably hear this from the exhaust manifold.
So, I unplugged the camshaft adjuster magnet on the exhaust side, and there was no more knocking and no more fluctuating readings from the SD.
But this diagnosis does not mean that the camshaft adjuster is broken. In my opinion, it means that there is no proper oil pressure at that particular moment to fill the cylinders in the camshaft adjuster, and the knocking noise is the same as when the pin is not working properly (in this condition, the pin is moved back because there is little pressure from the oil pump).
After examining the engine behavior and experiences from users here, as well as information from the German forum Motortalk regarding the knocking 271 EVO (CGI) engine, I have come to the conclusion that noises originating from the oil-emptying phaser of the variable valve timing on the exhaust camshaft are a design characteristic. However, after changing the oil to 10W60, my engine now runs 100% quietly. I wonder what design features of the 271 EVO (CGI) engine could be responsible for this issue.
The main modifications to the 271 engine (originally Euro 4) aimed at meeting Euro 5 emission standards include:
Raising the engine operating temperature from 87 to 103 degrees Celsius to reduce HC and CO emissions and increase NOx emissions.
Using layered supercharging (intake manifold with flaps) for better cylinder filling at lambda greater than 1.
Employing variable lambda from 0.97 to 1.05 for controlled NOx emissions.
Introducing a new oil pump with reduced oil pressure to decrease exhaust emissions by reducing energy consumption.
Implementing an alternator procedure (not charging during acceleration, charging by engine during deceleration) and start-stop system to reduce energy consumption and exhaust emissions.
Oil pressure of 0.5 bar at low revs is a value provided by the manufacturer but may be insufficient for proper operation of the variable valve timing actuators.
Using an oil thermostat set at 105 degrees Celsius may also hinder maintaining optimal oil viscosity.
An aggressive fuel injection system policy aimed at rapid catalyst heating may lead to significant fuel entering the oil system, reducing oil viscosity.
All above causing that oils like 5W30, 5W40 can't provide optimal oil pressure.
Hello, yes I fixed the problem, the problem is caused by the tensioner attached to the lanchester and crank gear, There is one plug on the tensioner, Since this plug is dislodged, the oil coming from the engine block goes back to the crankcase. therefore the oil pressure is low, When the oil pressure drops, the camshaft adjuster make noise. this tensioner needs to be replaced with a new one for solution. On my vehicle and on many of the vehicles we have solved the problem, the plug came out of the oil sump, and it probably is in yours. I am attaching the photos, if you have anything to ask about the installation, I will be happy to help.
"quoted"
Is it necessary to remove or loosen the transmission mount when you lifted the engine?
is the problem necessary to fix? Will it cause engine damage?
Like many, I too have had this problem for a long time.
painful (also to wallet). Changed the whole timing chain system but problem still persists..
Still in process of trying out other solutions i.e. seeing if the plug has dislodged itself etc
One interesting thing that happended was this old uncle mechanic tested by unplugging the solenoid magnets in front of cams and the sound completely disappeared. I know not advisable to do that but it was just to test the effect.
Conclusion is the noise is definitely something to do with the cam adjustment process. Just where are when and why it happens seems to be eluding all of us.
Like many, I too have had this problem for a long time.
painful (also to wallet). Changed the whole timing chain system but problem still persists..
Still in process of trying out other solutions i.e. seeing if the plug has dislodged itself etc
One interesting thing that happended was this old uncle mechanic tested by unplugging the solenoid magnets in front of cams and the sound completely disappeared. I know not advisable to do that but it was just to test the effect.
Conclusion is the noise is definitely something to do with the cam adjustment process. Just where are when and why it happens seems to be eluding all of us.
After examining the engine behavior and experiences from users here, as well as information from the German forum Motortalk regarding the knocking 271 EVO (CGI) engine, I have come to the conclusion that noises originating from the oil-emptying phaser of the variable valve timing on the exhaust camshaft are a design characteristic. However, after changing the oil to 10W60, my engine now runs 100% quietly. I wonder what design features of the 271 EVO (CGI) engine could be responsible for this issue.
The main modifications to the 271 engine (originally Euro 4) aimed at meeting Euro 5 emission standards include:
Raising the engine operating temperature from 87 to 103 degrees Celsius to reduce HC and CO emissions and increase NOx emissions.
Using layered supercharging (intake manifold with flaps) for better cylinder filling at lambda greater than 1.
Employing variable lambda from 0.97 to 1.05 for controlled NOx emissions.
Introducing a new oil pump with reduced oil pressure to decrease exhaust emissions by reducing energy consumption.
Implementing an alternator procedure (not charging during acceleration, charging by engine during deceleration) and start-stop system to reduce energy consumption and exhaust emissions.
Oil pressure of 0.5 bar at low revs is a value provided by the manufacturer but may be insufficient for proper operation of the variable valve timing actuators.
Using an oil thermostat set at 105 degrees Celsius may also hinder maintaining optimal oil viscosity.
An aggressive fuel injection system policy aimed at rapid catalyst heating may lead to significant fuel entering the oil system, reducing oil viscosity.
All above causing that oils like 5W30, 5W40 can't provide optimal oil pressure.
Yes, indeed. The latest oil sheets don't primarily focus on enhancing engine protection; rather, they prioritize addressing emissions concerns.
When considering the viscosity of 10W60 at 100°C, which is a temperature easily attained in the M271 evo, it's akin to operating with a malfunctioning thermostat or using 10W60 in a VW Golf that never quite reaches its optimal operating temperature.
As far as I'm aware, there's no specific approval sheet for 10W60. It seems that only the M113 AMG engines were recommended to operate solely with 5W50 oil.
Therefore, there's no need to fret over potential engine failures. Feel free to utilize it and do share your observations regarding any noise-related experiences.
01-03-2024, 02:05 PM
