M104 Engine Noise

[Seangbadee]

In the past 2 months I have used my 95 E320 as my daily drive, and put about 5000 miles on it .
Last week I started it after leaving it to rest for 4 days, and heard an unusual noise (valve lifters) which disappeared promptly. The oil indicator was on 3. After the car warmed up, I switched off and started again and there as no noise.
To err on the side of caution, I changed the oil and filter and everything was okay.
The last 5 days I did not drive the car, and whe. I started it up, the noise was there again. Within less than 1 minute it was gone. Again oil pressure was good and holding steady at 3.
Has this happened to anyone else? I do not know what to think, and I don’t want to start another topic on oil types etc.
Any suggestions?

 

[gerryvz]

Totally normal. An M104 that is not driven for a bit (and particularly in cold weather) is going to have a bit of lifter noise at startup, as they pump up with oil. As long as it goes away quickly, and your oil pressure is good, you're fine.

Old lifters can get a bit sticky and leak down a bit after a few days. Again, as long as the noise goes away quickly, you're fine and there are no ill effects. Oil viscosity isn't going to materially affect this.

 

[Seangbadee]

Okay I feel much better knowing that. Thank you so much.

 

[gerryvz]

I have owned three M104s (two W124 wagons, one W463 G-wagen currently). They have all done this. As I mentioned, it's a bit more pronounced in colder weather and after the car hasn't been driven in a few days or a week, or longer.

It can be alarming if you've not heard it before. I too thought it portended a major issue when I first heard it. It also may not happen every time after you haven't driven the car for a few days.

If it lasts more than a minute or so, THEN there is an issue that requires further investigation and remediation.

 

[Seangbadee]

I have owned three M104s (two W124 wagons, one W463 G-wagen currently). They have all done this. As I mentioned, it's a bit more pronounced in colder weather and after the car hasn't been driven in a few days or a week, or longer.

It can be alarming if you've not heard it before. I too thought it portended a major issue when I first heard it. It also may not happen every time after you haven't driven the car for a few days.

If it lasts more than a minute or so, THEN there is an issue that requires further investigation and remediation.

I spent about 5 days in Atlanta away from my 95 E320, and upon my return, I started it up and the noise was like a diesel truck. As usual it disappeared within a minute. It seemed more pronounced on the left (driver) side.
Any new information on this?
It never used to do this when I was still running 0W40 (from previous owner).
I now run Mobil 1 Fully synthetic 15W40

 

[gerryvz]

Again, as long as it goes away quickly there should be no problems. In colder seasons, I get a couple of seconds of this on my G-wagen (M104) if I haven't driven it for a week or so, on a cold morning. Otherwise it's fine. I use dino Chevron Delo 400LE 15W-40 diesel oil in my M104, as I have with all of the M104s I've owned over the years.

 

[gsxr]

I spent about 5 days in Atlanta away from my 95 E320, and upon my return, I started it up and the noise was like a diesel truck. As usual it disappeared within a minute. It seemed more pronounced on the left (driver) side.

Any chance this is the air/smog pump running? If it's internal, can you get a video at cold start?

 

[Seangbadee]

Any chance this is the air/smog pump running? If it's internal, can you get a video at cold start?

It’s not the smog pump because that has the characteristic on and off clicking sound. This sound is much more pronounced but disappears once the engine warms. The oil pressure is at 3, but it still bothers me.

 

[Seangbadee]

Again, as long as it goes away quickly there should be no problems. In colder seasons, I get a couple of seconds of this on my G-wagen (M104) if I haven't driven it for a week or so, on a cold morning. Otherwise it's fine. I use dino Chevron Delo 400LE 15W-40 diesel oil in my M104, as I have with all of the M104s I've owned over the years.

Thanks.

 

[rayhennig]

Sorry to revive an ancient thread but I always find this forum one of the best for informed feedback and it's, sort of, on topic.

The cold weather prompts this.

Stone cold start. Something rattles (deep rattle not tinny or lifter-like) in front of the engine - PAS pump, AC compressor, other accessory? It's been similar for years so I'm not overly concerned. I do recall VERY slight play on the PAS pump pulley but that was probably 15 years ago.

Rattle? No, deeper than that. The engine was out and overhauled in 2017 and is great. This noise has been apparent many years before that.

It may be slightly louder now but I can't swear to that.

New MB airpump was fitted a few years ago. Only the AC compressor and PAS pump are originals. Tensioner, belt, bearing bracket all more recent.

Any ideas? Anyone with similar?

Best to all.

RayH

 

[Alphasud40]

First step when trying to isolate a noise is to eliminate other potential sources of noise. I would remove the serpentine drive belt and let is sit the same duration. Then start it and observe. That will at least give you a direction to go inside the engine or focus on the ancillaries. Hopefully it’s just the air pump coughing up its guts and not an internal engine issue like a broken timing chain guide.

 

[rayhennig]

Hopefully it’s just the air pump coughing up its guts and not an internal engine issue like a broken timing chain guide.

Thanks for that. The air pump is new and the noise was apparent before its installation.

I'm pretty convinced it's external as it's much the same before and after the engine was out and restored 7 years ago.

As said, I've been aware of the noise for 15+ years, albeit that it MAY be louder now.

The only ancient parts are the AC compressor and the PAS pump. Maybe I should replace both when we address the minor oil leak from the timing cover.

R

 

[J. M. van Swaay]

You can see if it’s the smog pump by observing the magnetic clutch right after start up. If it’s engaged with noise present and noise stops when it disengage you’ll know it’s the smog pump. If I remember correctly, the smog pump is triggered to run on cooler/cold starts for about two minutes. My smog pump on my 95 E320 hasn’t run in 15 years because I removed the disc that the magnet sucks in to engage the pump….

 

[rayhennig]

You can see if it’s the smog pump

I'm pretty sure it isn't. The smog pump is only a few years old and the noise was apparent before the pump was renewed.

And the pump noise is more of a whine.

Oh well.

R

 

[yao500e]

Again, as long as it goes away quickly there should be no problems. In colder seasons, I get a couple of seconds of this on my G-wagen (M104) if I haven't driven it for a week or so, on a cold morning. Otherwise it's fine. I use dino Chevron Delo 400LE 15W-40 diesel oil in my M104, as I have with all of the M104s I've owned over the years.

my C36 m104 has that knocking sound. sort of like a diesel car, not as pronounced. it doesn't go away. car drives great. i had the engine rebuilt. port polished. pistons clean, rings cleaned.

this guys C36 in this video knocking sounds seems louder than mine but its similar.

any issues here? thank you

 

[TerryA]

Sounds like a noisy tappets to me.

 

[rayhennig]

Sounds like a noisy tappets to me.

That's what I thought. I always think MB 6 cylinders sound a bit 'clicky' but I've never worried about it. That's for 27 years with the 300-24 and others from '71 to '91 cars.

RayH

 

[yao500e]

Sounds like a noisy tappets to me.

what are tappets? thank you Terry.
edit:
just googled tappets. wow. learn something new every day. thank you

 

[emerydc8]

That video above almost sounds like a leak in the air pump hose before it goes into the exhaust. Or maybe it’s just the way the mic is picking up the sound. It sounds like a compressor running. Does this happen all the time or only when cold?

 

[yao500e]

That's what I thought. I always think MB 6 cylinders sound a bit 'clicky' but I've never worried about it. That's for 27 years with the 300-24 and others from '71 to '91 cars.

RayH

Hello Ray, are tappets fix a huge job? thank you.

 

[gsxr]

Hello Ray, are tappets fix a huge job? thank you.

Replacing the hydraulic lifters (tappets) is not difficult, but requires removing both camshafts. However, new ones may not change the noise you hear.

 

[rayhennig]

Replacing the hydraulic lifters (tappets) is not difficult, but requires removing both camshafts.

I can't comment on that as mine were replaced by the chap that did the overhaul. The only issue was the cost of 24 tappets at £35 each.

And 500 V8s will have 48 of them!!!

R

 

[R129 UK]

And 500 V8s will have 48 of them!!!

Only 32 so not so bad on the pocket

Plus, you probably won't need to replace them all.

 

[yao500e]

That video above almost sounds like a leak in the air pump hose before it goes into the exhaust. Or maybe it’s just the way the mic is picking up the sound. It sounds like a compressor running. Does this happen all the time or only when cold

Helly Emery, on my C36, its all the time but not nearly this knocking and loud. but there the sound is there. some people tell me its normal 3.6 M104. I am not sure.

 

[yao500e]

My C36 is an m104.941 just like this guy's w202 C280 and it does sound similar to this guy's car:

@rayhennig @gerryvz

Will this become a long term problem if not addressed?

Thank you all.

 

[yao500e]

Replacing the hydraulic lifters (tappets) is not difficult, but requires removing both camshafts. However, new ones may not change the noise you hear.

Thank you @gsxr

I hear all the time that noise isnt a problem but honestly, i am not sure. this is my 2nd C36 and my previous car didnt have this noise. what is truly the cause of it? this noise started after the engine rebuild.

 

[gsxr]

I hear all the time that noise isnt a problem but honestly, i am not sure. this is my 2nd C36 and my previous car didnt have this noise. what is truly the cause of it?

this noise started after the engine rebuild.

Ohhh... that is interesting. In that case the noise may be related to the engine rebuild. What work was done / what parts replaced?

Can you get a video of the noise from your engine (not someone else's)?

 

[gerryvz]

An M104 shouldn't be making any noise at all. The only exception as noted previously, would be a very very brief clack from the hydraulic lifters pumping up, in two conditions -- the car hasn't been driven for a few days, and the weather is or has been cold.

Any lifter clack should only last 2-3 seconds AT MOST until oil pressure has developed in a cold engine, and they have the opportunity to pump up.

10W-30 or heavier oil should be used - the M104s still are of the generation where they like thicker oils. 15W-40 or 20W-50 is good if you live in a temperate climate. Otherwise, 10W-30 or 10W-40 is fine.

Anything outside of this, there is something wrong. The valve cover needs to come off, and cams and lifters need to be inspected. If there is a knocking sound, there are problems that need to be found. An M104 should honestly always run quietly and like a sewing machine. They are a very smooth running engine when everything is in good shape.

 

[yao500e]

Ohhh... that is interesting. In that case the noise may be related to the engine rebuild. What work was done / what parts replaced?

Can you get a video of the noise from your engine (not someone else's)?

ok will do. ill get a video of my engine warmed up. appreciate it. @gsxr

 

[yao500e]

An M104 shouldn't be making any noise at all. The only exception as noted previously, would be a very very brief clack from the hydraulic lifters pumping up, in two conditions -- the car hasn't been driven for a few days, and the weather is or has been cold.

Any lifter clack should only last 2-3 seconds AT MOST until oil pressure has developed in a cold engine, and they have the opportunity to pump up.

10W-30 or heavier oil should be used - the M104s still are of the generation where they like thicker oils. 15W-40 or 20W-50 is good if you live in a temperate climate. Otherwise, 10W-30 or 10W-40 is fine.

Anything outside of this, there is something wrong. The valve cover needs to come off, and cams and lifters need to be inspected. If there is a knocking sound, there are problems that need to be found. An M104 should honestly always run quietly and like a sewing machine. They are a very smooth running engine when everything is in good shape.

im using 0w40 ans 5w40. could that be part of the issue?

ok got it. ill check on all of this. much appreciated and thank you

 

[gerryvz]

OMG -- WAAAY to thin of oil, don't use anything below 5W in an M104. If you look at the lubrication list that MB issued, you will see this.

0W and 5W should only be used in colder environments (as in below freezing temperatures).

10W-20W should be used in most and temperate climates (anything above freezing).

Here is the lubrication reference chart from MB, for these engines.



Personally, I have used ONLY 15W-40 oil in all M104s I have ever owned, going back nearly 20 years.

 

[gsxr]

im using 0w40 ans 5w40. could that be part of the issue?

For grins, try any 10W-40 or 15W-40 synthetic and see if there is a change in the noise level. Lots cheaper than tearing into the engine and replacing parts.

 

[gerryvz]

10W-30 or heavier oil should be used - the M104s still are of the generation where they like thicker oils. 15W-40 or 20W-50 is good if you live in a temperate climate. Otherwise, 10W-30 or 10W-40 is fine.

I think this is essentially the same advice that the @gsxr just gave you.

 

[yao500e]

I think this is essentially the same advice that the @gsxr just gave you.

ok great advice. Just ordered 15w40. coldest the car sees is 50 degrees and summers is hot 100+ degrees.

i went 0w40 or 5w40 was because i read. during start up, the thinner oil can spread faster to protect the motor parts and when it gets warmed up its at 40 weight. but i guess its wrong.

Thank @gerryvz. ill report back soon.

 

[gerryvz]

You only need that thinner oil when it is very cold out (well below freezing) and the oil’s viscosity and flow is reduced because of the cold. At 50F, you are fine with 15W-40. The thickness will help the lifters because they won’t drain so readily as they do with thinner oil.

I would trust the advice of experienced M104 owners here, over anywhere else that you read, with the exception of MB factory information.

 

[yao500e]

You only need that thinner oil when it is very cold out (well below freezing) and the oil’s viscosity and flow is reduced because of the cold. At 50F, you are fine with 15W-40. The thickness will help the lifters because they won’t drain so readily as they do with thinner oil.

I would trust the advice of experienced M104 owners here, over anywhere else that you read, with the exception of MB factory information.

Much appreciated Gerry. I learned my lesson! i will report back for sure.
For m104, should we stay with synthetic oil then or go to blended or non-synthetic? thanks again @gerryvz

 

[gerryvz]

If you used synthetic before, I’d stay with it. If you used blended or dinosaur, I would stick with those.

Going to synthetic with a middle or higher mileage engine is a recipe for oil leaks to start. On a lower miles engine it’s probably OK to start using it.

There is NO SHAME in staying with Dino oil with a M104. I always have and no problems ever. Change Dino oil and filter every 3K miles / 5K kilometers.

If you use synthetic you should go 5K miles / 7.5K kilometers. Not much more than that.

Remember, only Dino oil was generally used when these engines were new. So there is no problem in using it. People tho k you MUST now use synthetic and that is a fallacy.

 

[rayhennig]

5W in an M104.

MB used 5W40 in mine when they were servicing it from 1998 onwards. It's had the same diet for the last 27 years of my ownership.

It did have new tappets when they did the head gasket as it was already apart. £800 for the privilege was a mite steep. But no clicking now aside from 1 or 2 seconds after a few days switch off in 5C temperatures.

I'm happy.

RayH

 

[yao500e]

Just posted.Here is my C36 m104 after 30 minutes of driving at idle back in the garage. how does it sound to you guys?

after i put 15w40 in next week, lets see if it sounds any different.

Thanks all.

@gerryvz @gsxr

 

[R129 UK]

That does sound like a diesel engine…

 

[gsxr]

That does sound like a diesel engine…

Agreed. It doesn't sound like a normal M104 to me.

You mentioned the engine was recently "rebuilt"... assuming new crank seals were installed, there is ZERO concern about using synthetic. Even on high-mile engine there's minimal concern about leaks. That's a holdover from the early days of synthetics in the 1970's and 1980's... the additive packages have come a long way in 4+ decades.

 

[yao500e]

Agreed. It doesn't sound like a normal M104 to me.

You mentioned the engine was recently "rebuilt"... assuming new crank seals were installed, there is ZERO concern about using synthetic. Even on high-mile engine there's minimal concern about leaks. That's a holdover from the early days of synthetics in the 1970's and 1980's... the additive packages have come a long way in 4+ decades.

Yes. agreed. doesnt sound right to me either. I will change to 15w40 and see what happens. there are zero leaks. the engine is dry as a dessert. its amazing. i talked to some other C36 owners who tell me its ok and their cars sound the same. But again. some others say their cars are more quiet. this is my 2nd C36. Also a 1995. my first C36 was smooth and quiet. thank you.

@R129 UK @gsxr

 

[R129 UK]

Can you clarify exactly what work was done on the engine as part of the “rebuild” and also the status in terms of engine noises before this?

 

[yao500e]

Can you clarify exactly what work was done on the engine as part of the “rebuild” and also the status in terms of engine noises before this?

the main job was cleaning the pistons, rings, port polish the head, new bearings. etc. i attached some pics of the before after rebuild.
I assume hydraulic lifters should have been addressed on this rebuild.
I can ping my engine mechanic and get the full details. thank you. @R129 UK

 

[gerryvz]

Just posted.Here is my C36 m104 after 30 minutes of driving at idle back in the garage. how does it sound to you guys?

after i put 15w40 in next week, lets see if it sounds any different.

Thanks all.

@gerryvz @gsxr

That generally sounds OK to me. I am not hearing anything in the video that is overly loud or egregious. Sounds like pretty normal M104 noise, to me. Try the heavier oil and see if it calms down that valvetrain noise a bit. I bet it will.

To clartify, WHILE IT IS OK TO USE 0W or 5W engine oils, per the chart I posted, and they are OK to use for all temperature ranges, please notice that for temperatures above 0C / 32F, heavier oils are generally specified. The M104 (as the M117, M103, M119, M120, etc.) generally likes heavier oils whenever possible.

15W-40 diesel-rated oil (which has extra detergents, and which keeps the internals of the engine very clean) is an excellent grade that is right in the middle of the 10W-40 and 20W-50 "sweet spot" for warmer climates where freezing temperatures are not a factor.

If you would like to see the effects of long-term use of 15W-40 diesel-rated motor oil (also rated as acceptable for use in gasoline engines), of the Chevron DELO 400 brand, in an M104, in terms of the cleanliness of the inside of the engine, you can check this forum's M104 Top-End rebuild thread, specifically this post.

 

[rockstarger]

This "diesel" noise is in my opinion pretty normal. Even if you google "c36 amg diesel noise", you will find forum posts from 2004 with the same question. If your engine does NOT make this sound when its an cold start, then everything is okay. I also own a C36 and the sound is pretty similiar when the car is hot. One friend replaced all lifters and he still got the same sound.

 

[gsxr]

This "diesel" noise is in my opinion pretty normal. Even if you google "c36 amg diesel noise", you will find forum posts from 2004 with the same question. If your engine does NOT make this sound when its an cold start, then everything is okay. I also own a C36 and the sound is pretty similiar when the car is hot. One friend replaced all lifters and he still got the same sound.

Good information! Is this noise unique to the 3.6L AMG engine?

I don't recall my 3.2L M104 sounding so diesel-y.

 

[rockstarger]

Yes, it should be unique to the 3.6. When somebody is not sure if the engine has been replaced with a 2.8L, then some people are saying: "when you hear the diesel noise, its an amg" It's pretty interesting to browse through the very old internet post when searching for this sound

 

[yao500e]

That generally sounds OK to me. I am not hearing anything in the video that is overly loud or egregious. Sounds like pretty normal M104 noise, to me. Try the heavier oil and see if it calms down that valvetrain noise a bit. I bet it will.

To clartify, WHILE IT IS OK TO USE 0W or 5W engine oils, per the chart I posted, and they are OK to use for all temperature ranges, please notice that for temperatures above 0C / 32F, heavier oils are generally specified. The M104 (as the M117, M103, M119, M120, etc.) generally likes heavier oils whenever possible.

15W-40 diesel-rated oil (which has extra detergents, and which keeps the internals of the engine very clean) is an excellent grade that is right in the middle of the 10W-40 and 20W-50 "sweet spot" for warmer climates where freezing temperatures are not a factor.

If you would like to see the effects of long-term use of 15W-40 diesel-rated motor oil (also rated as acceptable for use in gasoline engines), of the Chevron DELO 400 brand, in an M104, in terms of the cleanliness of the inside of the engine, you can check this forum's M104 Top-End rebuild thread, specifically this post.

you really made me feel better! thank you Gerry. I will report back with 15w40 oil for sure. i will also check out your m104 rebuild post. thanks again. @gerryvz

 

[yao500e]

Yes, it should be unique to the 3.6. When somebody is not sure if the engine has been replaced with a 2.8L, then some people are saying: "when you hear the diesel noise, its an amg" It's pretty interesting to browse through the very old internet post when searching for this sound

hello @rockstarger . what year and color C36 do you have? thanks for the reassuring information. I have an E500 which is why i am here but i baby and pamper that car. My C36 has over 100,000 miles and a drivers car that i take are of. i drive it 3 times a week or so. E500 i drive at most 1 time a month. put about 2000 miles a year on her at most.

@gsxr its great to learn new things on m104!

thanks both.