RWagz

With a few "lifter ticking" searches in the forum I have come across several engine types, but I am unsure whether those messages/responses apply to my older M272 engine.

I'm hearing what sounds like one collapsed lifter at idle and normal operating temperature. It is loud enough to hear inside and outside the car. This noise either ceases at higher RPMs or it could be getting drowned out out by overall noise.

I changed the oil and filter to ensure that MB 229.5 spec oil is used. I was unsure whether the last shop used MB spec oil. With the oil change I ensured that the oil level is at the top of the dipstick range.

The sound persists. Is this common on the M272.980 engine? I haven't pulled the valve cover to see if there is any sludge.

Is this noise benign? It sounds more annoying than scary. Is this something I just have to accept due to it being 12 years old with over 100,000 miles?

I obviously want to avoid tearing this apart if the noise is benign.

E55Greasemonkey

Every 272 I've heard makes a tapping sound, best heard outside.above the passenger tire. It's normal.
It doesn't have valve covers per se. Please do yourself a favor and don't touch it.

RWagz

I found something relevant here that also says "leave it alone"
https://mbworld.org/forums/e-class-w...l-me-what.html

I'm lazy. Leaving it alone knowing it won't degenerate and fail due to this noise is fine by me!

Senecat

Being OHC, lifters are obvously a non-issue, and not sure if that description helped or distracted from the actual issue. Rotating assembly ticking is obviously a bad thing, but often those are mistaken for timing components. Post a video of the condition.

Whenever I start hearing a noise, I start probing around with one of these:

https://www.harborfreight.com/mechan...ope-63691.html

S-Prihadi

Fuel vapor purge valve also makes noise. I do not know its position on your M272 engine.
On mine it is very close to LEFT HEADLIGHT ( Driver side for USA ).
https://mbworld.org/forums/e-class-w...rge-valve.html

There is a way to ID the noise. Record it at loudest source.
Edit in a video editor with capable audio portion. Find the noise waveform.
What you want is the frequency of the noise.
We know that crankshaft RPM if at say 1,000 , that means camshaft is at 500 RPM.
Assuming the noise waveform pops out in the video editor and is visible, you can at least ID its frequency/RPM and narrow the search.

If say the noise is a 500 RPM one, a 30FPS video can capture it 500/60seconds = 8.3 spikes ( 8.3hz ) per second on the audio file

If you have a scope, you can narrow it down to INLET/OUTLET valve opening/closing events , if suspect is indeed the lifter.
There is a special mic for scope use

toledotom

When mine starts to get loud I put in a Bottle of Best Line Engine oil Treatment with Diamond - Nano treatment. works great! A half a bottle should do the trick!

atraudes

I'll be rebuilding the passenger head sometime this year to remedy this issue. Stay tuned to see how that goes O.o

They all make the noise and it seems to be harmless but I just can't live with it. It's embarrassing.

cvx5832

183k miles living with that tick and it hasn’t gotten better or worse. I’m inclined to leave it alone.

Senecat

In your E63 service entry "06-20-2020 51335";

What fluid transfer pump are you using? Looks orange? You are refilling the diff with this pump, correct? Thanks!

Sorry for off-topic.

RWagz

FWIW, I use a mityvac 7201 for oil changes. Typical use is to draw the oil out, reverse the pump, and discharge the oil into recycling containers.
I plan on using it to change out diff fluid and refill/change the transmission fluid. Great tool for $100 (in 2019)

Senecat

Thanks man. I always drain from the pan with oil changes. I just need a smaller, medium-volume pump like the one in that pic for diff and other stuff. That Mityvac looks nice though. I may get it just to try a from-the-top oil change just for the hell of it.