I appreciate that, to give you good noise clips I would need to go back to the old oil. For now the engine is pretty quiet. Today's start was in the best possible environment to hear the noise, parked between two cars, my driver door was open and I was listening. It started pretty darn quiet. There was some noise for less than 5 seconds but nothing that grabbed me and said, we have a problem here.

This forum has given me many tips on repairs on these cars and I appreciate each one. Every car is different and tips on the forum have saved lots of time. I try to help if I can but my areas of knowledge do not cover most of the car. So no video available for sound checking unless the 20-50 fails then I will go after the noise again. Spell check on my computer keeps changing Oil Drain Back to drawback, that was not my intention. I need to double check my typing.

 

Never mind video, I don't know either how to produce a video... Sound alone would work just fine


-- Let me give you couple more nails for your issue...

-- HPFP gets the very least amount of lubrication where it is located at Bank1 rear end, furthest away from the under-reved dual-rate oil pump. Read HPFP has marginal lube conditions.

-- HPFP is also the proven bad guy that cause B1 Intake VVT to always wear out first.

-- Double check how your fuel rail pressure behaves under heavy load. Perhaps HPFP is weak and ready to go. I know you got it out for PCV replacement. Are your LTFT nearing +10 ..?


So for me (HPFP + Roler) are prime candidates.
No rush, it's pumping and everything is running more quiet on 20W-50.





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bro your replies are always amazing. The forums are insanely lucky to have you Cali.

 

Cold start this morning, quiet, I am starting it with the door open to hear as much as possible and it is quiet. I would say 98% better than before. If it stays like this I am very happy. Time will tell. Only drove it 20 miles or so yesterday so the oil is still very new, less than 100 miles total on this oil change. If a problem comes up due to the heavy oil I will deal with it. I have pulled an E350 engine before, pulling them is easy, tear down is more complicated than most engines I have rebuilt.

On the High Pressure Fuel Pump, mine has been removed, checked and re installed, roller was smooth as glass. Fuel trims and pressures were perfect. I only removed the HPP on this car to replace the valve cover vent due to finding oil in the intake when I had the valve covers off. I do think the Mercedes PCV (positive crankcase ventilation) system is less than good. Oil should not reach the intake, oil in the intake reduces the gasoline octane along with creating pollution. I was not aware the Turbo engines have an improved PCV, might have tried to incorporate that at the time.

 

Where do you think the crankcase vapor, full of oil, goes if not back through the intake to be combusted?

 

Crankcase vapor on all engines has to be managed. From your lawnmower to the largest engine running.

Vapor is usually more of a problem with bad piston rings in an engine. Every time the engine fires some pressure from the explosion ends up in the crankcase. On a well sealed ring set the amount is very little. On a poorly sealed ring set the amount is a lot. Prior to the early 1960’s engines had a Road Vapor Tube where this vapor was directed down out of the engine onto the roadway. It was not uncommon to see those old poorly sealed engines puffing smoke out the draft tube.

On modern engines that are broken in on a Dyno the engine will have lots of blow by on start up but after the first hard acceleration which puts lots of pressure on the piston rings the rings seal up and this blow by is 98% gone.

If the PCV or Positive Crankcase ventilation system is not designed well or has a problem lots of oil can be pulled into the intake, not in vapor form but in wet oil being sucked into the intake manifold by the manifold vacuum and a failed PCV system. Vapor in the system is re submitted into the intake charge and burned along with your gasoline. It is such a small amount that over 5,000 miles of driving your dipstick level does not change.

If your system is using a quart every 1-5,000 miles something is not working as designed. Some engines have better PCV systems than others. Some fail and start consuming oil before 100,000 miles. GM had one truck engine 5.3L around 2010 that was sucking oil, about 1,000 miles per quart. A new Valve cover design stopped the oil splash from being sucked into the manifolds and cured the problem. These engines still have vapor to manage but no longer suck in oil splash and oil consumption is eliminated with a better PCV system in the new valve cover.

If you wish to know if your engine has blow by remove the Oil filler cap and cover it with your hand to seal it. If you feel pressure pushing your hand up your rings are not sealing well. If the pressure is minimal as it should be the rings are sealed well. You will still have vapor to manage but it is minimal in engines and a good PVC will manage it without allowing your engine to consume oil.

When I removed my E350 Manifold it had oil in it. I knew where it came from and replaced the PCV, Mercedes has another name for it. Have not removed the manifold again to see if it is working proper but I assume it is.

Mid 2000 BMW V8’s have the same issue, if you pull the vent tubes where they enter the intake manifold many are very wet with oil. The BMW PCV is not working well. It is a poor design with a short functional life.
Lots of the BMW owners replace valve stem seals thinking that is the cause but a wet intake is only caused by a poorly working PCV system.

As mentioned all engines utilize some method of PCV, when you remove the intake manifolds on engine tear down most are clean and dry with just a stain where the PCV dumps its air into the manifold. Bad systems leave the intake manifold wet. My E350 had enough oil in it to pour some out, probably less than 1/8 quart but it does not belong in the manifold.

 

It is easy to verify PCV system without removing anything troublesome, say twice a year as preventive check.
Read the crankcase negative pressure thru the oil dipstick using high sensitivity digital gauge, which is low cost today.
While oil filler cap test is do-able, it does not give an exact number for reference.

Mine warm idling 600 RPM with coolant at 81C, I get -35 millibar approx.
Too bad MB WIS does not provide crankcase negative pressure values like BMW

Where you see a 7 on engine model, that is diesel if for BMW list below :


.

 

20-50W oil follow up. Car sat for two days. A good drain back test. Started this morning QUIET. Time will tell but this is looking positive.

The 20-50 is much thicker when cold, ( 0 or 5 W vs 20 W). but only a jump from 40 to 50W when hot. If I lived in a COLD state this might be a problem. In my climate it might be a solution.
So far I am really liking the results. It has been quieter each day on start up so far. This has to be better for the engine than having all those metal parts rattle on start up.

This oil debate was only to help with oil drain back because the anti drain back valves are not working. This would not help or change a broken cam adjuster.

 

Fired up this morning, I am being super critical, trying to verify if it still has the start up rattle or not. Today I did hear a small amount of rattle, just a second or two and gone. It was far less than it had before the oil change but a slight amount detected. At least 90% better than before the oil change. Odd that I heard nothing yesterday after a 2 day park but heard a faint amount today. If it stays the same I will stop reporting, if it gets louder again I will report back and update this post. For now, it is so much better I can live with it and forget it. Thanks for the consultations and ideas.

 

This is how mine is, 2-3 second s of noise, then gone. I have always used 10W-40 or 15W-40 in my car since the first oil change, if I was not in the rust belt, I would try 20W-50 also

 

2-3 seconds is not bad, I think mine was at the 10-15 seconds time frame before this oil change. When did you swap to the 10 or 15W oils? Was that due to start up rattle also?

 

six months in at the first oil change, I worked at Lubrizol for a number of years, 0 weight oil was engineered for gas mileage alone, not engine life or lubrication capability. They did not have good results from engine stand testing even with the 5 weight oils tested at the time, coudn't get pump pressure at start-up or good oil cling to parts at shut down

 

Good points and I think we witnessed that first hand in these engines. On the engine side of the business we did see that Roller Lifters liked the thin weight oils. The rollers are small and thicker oils take longer to get inside and lubricate them. Hope we do not bump into an issue with the roller lifers failing due to our changes but quiet starts are a nice change for sure.
The other thing I thought about is the Chain Driven Oil Pump, I hope we are not adding to much load on that chain and tensioner. Every change always has another side to it so maybe the next oil change I will drop back to 15-40 and listen for any more start up rattle.

 

I had my first morning rattle after the oil change yesterday, went at least 5 seconds. Very disappointed, was hoping to have this issue fixed. I will continue to track it, if it gets worse or if I get bored I will take the engine apart and try to quiet the rattle. A couple of the first mornings I heard only the faintest hint of what it used to be but this time I heard it almost exactly like before but it has been 109*. Maybe the Cold Start test is now a Hot Start test. So maybe it bleeds down more when it is so darn hot outside. It formerly did this even on cold mornings. I don't want people getting excited and swapping oils only to be disappointed. Odd that it took a week before hearing the old noise. After writing the first sentence I went out and fired it up today. Maybe 1-2 seconds of noise and gone. No idea why yesterday and today differed. Temps were 108 and 109*. Darn Hot in my area. Hope all had a great 4th of July.

 

West,
Have you had the actual oil pressure tested for pressure and speed of pressure rise in cold and warm start ?

 

I think Cali talked about the HPFP already in more than one of his posts. You mention that your pumps were removed and inspected and they looked ok but did you inspect/measure the backlash at the roller lifter of the pump?

i had a 2013 S550 that developed a rattle. This rattle was not present only at cold starts. It could surface out of nowhere while car was idling after a drive.

Thru these MBWorld forums I focused on the fuel pumps and without spending too much time trying to troubleshoot the issue I ordered both pumps and lifters and replaced. Result was no rattle at all other than the normal valve train noise.

Looking/feeling the pumps did not reveal anything but I did notice wear at the contact point between the pump and the lifter. There is a small “button” contact point about 4-5 mm in diameter that had worn on the lifter side.

I don't know what backlash MB designs these lifters for. If it was me I would make them without any backlash as with the pump you don’t need to worry about holding something open when it needs to be closed, like is case with the engine valves. No backlash is the best for any cam drive if possible to make. This is the reason for hydraulic valve lifters that keep backlash at zero during engine run yet the pressure in the lifter is not high enough to keep valve open. If the HPFP lifters were designed to have zero backlash but wear causes it to form then you have a problem.

A sound recording was asked as analyzing it for frequencies could tell if it has cam shaft speed (engine speed) in it that timing chain rattle does not have.

As I mentioned the pump and lifter change completely took care of the noise in my case. After seeing the lifters I was thinking the problem probably was only with them but proceeded to replace also the pumps as I had them and had it torn apart already.

 

Here is a video of the first time I measured the oil pressure on my SL400 M276 3.0 L Turbo engine. Notice that it took about 7 seconds from when I started the engine to when the gauge started to move. Now, it's never done that again. This was the first time using this pressure gauge, so there may have been some air in the hose that needed purging. But assuming no oil pressure to the cams, timing chain tensioner, etc., 7 seconds is an eternity.


Subsequent start about 5 months later.

 

My rattle is a Timing Chain rattle, much faster cadence than a single cam lobe or a single loose lifter. Maybe 10 times faster than a lifter noise. It is not bad at all, I am just really picky when it comes to my engines. I like them to perform as designed and these engines did not have a timing chain rattle on start up when new. Fired it up this morning, it sat all day yesterday in 110* heat. We are in the hottest heat streak I have seen in my entire life. Maybe the heat helps it drain down. Fired up with timing chain rattle for 1-2 seconds then instantly quiet. Better than before the thicker oil but it is still there. Thinking back, before the anti drain back valves were installed this engine had this rattle on every single start. Not only when it sat overnight so the anti drain back valves and new tensioners did help, they just did not fix it completely. It still has the same noise, just not as long and now only on cold start in the morning or after sitting many hours, 12 or more. . I can let is sit for 4 hours after running and it will still start quietly. Just a long park causes the issue. Rules out oil pump issue. Oil pumps work the same on every start.

One of the above videos showed a very slow oil pressure pick up. You normally see this when an oil filter has been changed and pressure does not build until the system fills with oil again. Some engines use an Oring to seal the Oil Pump Pick Up tube. As these O rings age they get stiff and hard, do not seal as well. On cold start the oil pump pulls air rather than oil until that Oring gets covered in oil again and seals. Some get so bad the engine can’t hold oil pressure at idle and it starts triggering the low oil pressure warnings. This is sad because you spend 12 hours labor to fix a $3 Oring. I do not think Mercedes uses the Oring design. I have had one apart and do not remember how the oil pick up tube was mounted to the pump.

 

M276 3.5NA or my 3.0 Turbo uses o-ring for oil pick up and long snorkel made of plastic, which is also the windage tray. If 4 Matic, it uses 2 o-rings for oil suction plastic snorkel/pipe.

Here : https://mbworld.org/forums/e-class-w...brication.html

Extra : https://mbworld.org/forums/e-class-w...no-gasket.html

 

Well then,

you do not need any more help. You have already done everything there is to do to fix the rattle that you KNOW is the chain rattle, fixes that I have read over the years in this forum that have helped everyone else that I can recall. Typically it only takes the back-flow arrestors, but most also replace the tensioners while they are working under the cover.

Just for your info, that you also probably already know, a sound recording analysis can find and separate the cam shaft frequency from the “sound mess” that for human ears may sound much faster frequency. Like when the pump lifter starts bouncing against the cam shaft other than just when it is supposed to hit the raising lobe.

Other members have offered you a free sound analysis but you are stuck to just the oil viscosity and do not want to take 10s sound recording with your smart phone to post it and let our magicians do the work on it. You might wake up when you find your oil pump drive, the cam shaft, beaten in pieces by the pump lifter.

Higher viscosity oil will help any lifter noise in the engine but it can cause delay for some parts in the engine cold start that require fast low viscosity oil flow. Lifters needle bearings have been mentioned as such already.

But hey, it is your car. Happy motoring and perhaps I and some others can offer help to you under some other topic. This one is dead.

 

I guess I ticked some emotions off. Not my intent, just wanted to share the attempt to quiet the engine. I did report the good and bad and clearly stated the risk involved for others that may try it. No intent to demean any other poster as I have been helped many times over the years by helpful members on some very difficult to repair issues. Most of my experience in engines is outside of Mercedes specific engines so some experience relates directly, sometimes it does not help at all.

One thing I did not do that still has me thinking is sealing the chain tensioners on install. I have to say I did not consider a bad surface on the mating surface of the tensioner and block allowing the drain back or oil pressure loss when parked. I think it was Cali that offered his tip to make sure that surface is flat or to seal it on install to avoid leaks from that mating surface. Something to consider that is not hard to access.

Getting a sound bite would be simple if I had a helper on hand when doing the morning start. I have not had that yet. I tried reaching in the window and starting while filming. I could not do the reach in start. When I got in and started it the sound either did not happen or I was not even half out of the car when it was gone. It really is minimal now.

Yes, being in the engine rebuilding industry for 30 years I have probably heard more failed engine sounds than most people. My ears are not what they were 30 years ago but they are still pretty good telling Chain rattle from Fuel Pump Rattle, Lifter rattle, main bearing failure, rod bearing failure, Piston Scuff noise or Piston Slap noise, broken valve spring noise etc and I did have the fuel pump piston from this car in my hand looking at it before I installed it, I liked the fit and finish, did not detect any issues at that time which was only 4-5,000 miles back. But every car is unique and I have only worked on two of this exact engine so it is still very new to me with lots to learn yet. Have a great weekend.

 

Can you tell which side is making the noise?

 

No, I have not been able to ID the location. Again, I have been doing this work alone and it goes away so fast it is hard to track. When I have a helper I will get more info. taking it on a 1,000 mile trip in a couple weeks so should gather more info.

 

Got email from Baxter Performance, They are going to look into the M276 design and function of oil system from pump to filter, verify if it has a drain back valve or not.

If not, they can certainly make an adaptor for it that will have an anti-drain back valve. The ones they make for other MB, Mopar, GM engines of this style are $399. Certainly worth extending the life of the engine and getting rid of that rattle once and for all.

 

Follow up once more for those interested. As the mileage has increased I am getting noise on start up again. The car has maybe 3500 miles on it since the 20-50w oil install. The weather has changed, much colder now, morning start ups are maybe in the low 40* range.

I do not think the oil is failing at this low miles check. I suspect the thick oil does not like the cold starts.

I have also found the engine is not as responsive at first start. After temps start to come up it runs normally again. I believe in the cold weather the cams do not like the thicker oil weight and are not responding at first due to the thicker oil. I only notice this on the first 1-2 miles after a cold start.

The start up noise is still short but now maybe 10 seconds before it quiets. Before this oil was installed I had about 15 seconds of noise. Sorry, I still do not have an audio clip to share.

So was this a success to go with thicker oil. No, but it was much better in the summer months. We have taken two long trips in this car recently, 1,000 miles each time. MPG was very good, 28.5-31 MPG running 70-85 for most of the trip.

The range in these cars is amazing, nearly 600 miles on a tank and it still had some range left over. This car does have the optional extended range tank, not sure how many gallons that adds but I like it.