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There's a factory "tool" to measure the oil pressure.
It's a filter cap with a threaded hole at the top. You install a fitting that goes to a shop gauge there.
I thought about the same thing as the OP, to drill the existing and buy a replacement.
But if the factory drilled one were to be available, I would consider using it to install a permanent pressure sensor in it.
I'm not sure yet where I would put the gauge.
I didn't think this would help.
Do you have the car stethoscope, maybe you can single out which camshaft is noisy and just replace that cam?
Again, not that you need it, your car's noise is minor, it's basically fine.
That's a different test.
And at onset, that knock wont follow up into the rev range.
I would not tear into the bottom end though, but it's up to you....
Good luck
The bearings are never broken. Worst case scenario they can be spun.
They can have abnormal wear, which can cause the knocking noise.
I can't speak about the M156 symptoms and BTW I can't find any mention of this happening and on the contrary, I see people posting of how beefy the bottom end is on these engines.
But, if we were to speak on a general level, that's a very bad situation. Bad, because once the knock is loud, the engine is contaminated with metal debris. You can clean it until the end of times, chances are that once it's fresh and rebuilt and it has that fresh oil running through it, somehow, from the depths of the lubricating system, debris are going to come out. They will not come out right away, but will show up in time. The large ones will get removed, but the fine ones that cause... abnormal bearing wear.. will be there, it becomes a ... downward spiral.
That's why you can also not reuse the oil radiators and coolers and so on..
Anyway, so in order to avoid complete annihilation, people try to catch the rod knock early on.
Rod knock starts by being discrete, a mild rraping noise at low RPM.
At that stage, it does not increase with RPM, it shows up briefly, then gone.
The thing is, even the smoothest engine has normal noises, which easily cover the initial rod knock, so you can only hear it in the low RPM, when all other noises are low.
The other thing is, you have to simulate load, it will knock under load, not by revving or holding rev.
Load doesn't happen by revving in neutral.
So here's the idea of the test. Create load at low RPM in a quiet location.
The way people do this is by stabbing (not revving) the throttle, for low RPM, don't let it go over 2000-2500 RPM. Don't give it brutal stabs, as the induction noises will be too loud.
I've seen mechanics load it against a gear, holding the brakes, kinda the way you check motor mounts.
And in a shop, put it on a lift, running, with a guy that can operate the throttle and listen from underneath.
When I was working in a shop in the early 90's that was diagnostic by agreement, meaning the foreman and oldest mechanic had to listen together with the mechanic that worked on the car and all 3 had to agree that it was rod knock.
Anyway, so if you don't catch that early on, once it starts knocking freely, it becomes loud very quick, it announces itself..
It could mean any of a number of different things:
-change of part suppliers due to better pricing to Mercedes by the supplier.
-change in design for compliance to this or that standard, or carbon footprint/recycling concerns for instance the replacement rods which require new bearings could be lighter weight.
-change designated to bring them savings by standardization, now they use the same rods in several engines. Or the opposite, they have to branch out with the E63 because it's rated for more torque and this affects the rods primarily.
-change in design for reinforcement, or following customer complaints. I have not seen the complaints, nor read of any class action lawsuit about bearings in the m156.
And this type of part number substitution can be seen all the time in the industry, is not unusual.
For me it sounds like bearing in conneting rod. It didnt spun yet and this is a good moment to replace them. Here is the foto of bearings with abnormal use in my other car (FX 35 2005). The car was making the same sound
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Sounds normal. Sounds broken. Sounds like lifters today it sounds like rods. I wonder if it's rod bearings. What should I have for lunch today. I think chicken salad sounds good. That sounds actually like cam adjusters. No it's definitely rods. Sounds normal to me. Who's on first? No what's on first. Why? Why's in center. Repeat.
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Originally Posted by Tomek63
What does it mean? I am not very well in english
By my count, 8 people said "normal", 3 said "lifters" and 1 says "injectors".
Nobody thinks anything is wrong here.
But you keep posting more videos, expecting people to diagnose your car from sounds over the internet. And although you replaced the lifters, the overwhelming majority of responses say that's lifter tap.
You think it's rod bearings now? Great. The only way to find out is to change them and let us know if it worked.
It can only be so many things. If you are convinced it's not lifters or cams, you're going to have to start taking things apart to find out what you think is wrong. I don't think more videos is helping anything here, do you?
2012 P31 C63 Coupe Trackrat, 2019 GLE63S Coupe Beast
Got it, my bad. But my post still stands. I mean, I guess I'm just trying to figure out what the OP is looking for at this point. Everyone says it sounds either normal or like lifters, but the OP keeps posting videos. I'm not sure what he's looking for.
I'll start out by saying that I am in no way, shape or form a mechanic...
However, the last video that was posted (post #66) does NOT sound normal at all. My car is a very healthy car and it definitely does not tick like that at startup, idle, revving, etc.
IMO, you need to take your car to a dealership that has a specialized AMG engine mechanic (there's one here in the Twin Cities). They should be able to help you diagnose and fix that noise. The people in this forum are very helpful, however... 1) they are not certified AMG mechanics, and 2) they are trying to help diagnose your AMG engine problems via YouTube sound clips.
02-28-2017, 04:22 PM
