Engine oil overfill

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The main long term danger from overfilling with oil is if the crankshaft aerates the raised oil by constantly striking it causing a lot of air entrainment which might in turn promote a degree of oil starvation to the crankshaft , timing gear and big end bearings. The affects of this would only be apparent in the shape of reduced engine life. If you have not experienced what is euphemistically termed "sudden increased engine noise" its likely you have got away with it
 
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The main long term danger from overfilling with oil is if the crankshaft aerates the raised oil by constantly striking it causing a lot of air entrainment which might in turn promote a degree of oil starvation to the crankshaft , timing gear and big end bearings. The affects of this would only be apparent in the shape of reduced engine life. If you have not experienced what is euphemistically termed "sudden increased loud engine noise" its likely you have got away with it

I believe its the m271 evo engine that I have, the only thing I have noticed up to 40 mph when accelerating I hear a light clatter sound which increases in speed from the engine, at idle it is fine.

Its more noticeable when i gradually increase in speed and immediately when i put my foot down and seems to disappear above 40 mph

Is this a characteristic of this engine?
 
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One major weakness of the M271 engine is found in its timing gear ---chain jumping /worn sprockets / worn tensioner - lots of threads on this on the forum and how to check for it - you may have had a degree of wear anyway - so may or may not be related to your oil overfill.
The Complete M271 Engine thread. ( Revised and Updated )

I've had a brief read, is it easy to check for it?

The car has only done 36k could it happen so soon?
 
Wear assessment/renewall is via a partial front end stripdown visual inspection and component replacement.If contemplating such action I would recommend entrusting the assessment and repair to an MB specialist experienced in such matters.Normally you would expect a small amount of timing gear noise from this engine and at 36k you should not have much to worry about barring any oil starvation incident or lack of maintenance/regular oil change. Perhaps best to just keep a watchfull ear out in the meantime and any major increase in timing gear noise would warrant a rapid response from you because timing gear failure is an engine wrecking event.
Preventive maintanence M271 engine, timing chain & camshaft adjuster sprockets. - Mercedes Benz SLK Forum
 
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Wear assessment/renewall is via a partial front end stripdown visual inspection and component replacement.If contemplating such action I would recommend entrusting the assessment and repair to an MB specialist experienced in such matters.Normally you would expect a small amount of timing gear noise from this engine and at 36k you should not have much to worry about barring any oil starvation incident or lack of maintenance/regular oil change. Perhaps best to just keep a watchfull ear out in the meantime and any major increase in timing gear noise would warrant a rapid response from you because timing gear failure is an engine wrecking event.
Preventive maintanence M271 engine, timing chain & camshaft adjuster sprockets. - Mercedes Benz SLK Forum

I thought Mercedes had addressed this issue, wouldn't have thought this to be still an issue on a 2011 vehicle!

From what I've read is to look out for the engine management light and significant clatter noise at start up which is also present at idle
 
The premature timing gear failure issue affects all M271 engines, including 1.8L and 1.6L, Kompressor and Turbo, up until when the engine was retired in 2014/2015.

MB did try and modify the timing chain around 2009/2010, however this did not completely resolve the issue.

The newer 4-cyl petrol Turbo engines - M270/M274 - 1.6L and 2.0L - introduced on some models from 2012/2013 - also have a single chain design but do not suffer from this issue.

The cause of this failure is a combination of weak/soft camshaft sprocket wheels and single chain that can stretch and wear the sprockets.

The timing gear issue will occur sooner if the oil isn't changed at the correct intervals, or if the wrong type of oil is used (should be MB 229.3/229.5), but it isn't related to oil overfill as such.
 
The premature timing gear failure issue affects all M271 engines, including 1.8L and 1.6L, Kompressor and Turbo, up until when the engine was retired in 2014/2015.

MB did try and modify the timing chain around 2009/2010, however this did not completely resolve the issue.

The newer 4-cyl petrol Turbo engines - M270/M274 - 1.6L and 2.0L - introduced on some models from 2012/2013 - also have a single chain design but do not suffer from this issue.

The cause of this failure is a combination of weak/soft camshaft sprocket wheels and single chain that can stretch and wear the sprockets.

The timing gear issue will occur sooner if the oil isn't changed at the correct intervals, or if the wrong type of oil is used (should be MB 229.3/229.5), but it isn't related to oil overfill as such.


Cheers mark, hopefully this doesn't happen to my vehicle!

Will definitely do regular oil changes on time with mercedes 229.5 oil
 
There are 4.54 litres to the gallon, so 9.5 liters = 2.09 gallons, that's a lot of extra oil for a sump that holds 5.5 liters (1.21 Gallons).
 
There are 4.54 litres to the gallon, so 9.5 liters = 2.09 gallons, that's a lot of extra oil for a sump that holds 5.5 liters (1.21 Gallons).

The sump can definitely hold alot more! I put 5.5 litres back in and this is showing between min and max on the dipstick
 
The sump can definitely hold alot more! I put 5.5 litres back in and this is showing between min and max on the dipstick

Has the vehicle got the correct dipstick in it?
 
Has the vehicle got the correct dipstick in it?

From the other dipsticks i have seen they look the same

Someone else confirmed what I had said that 5.5 litres takes it between min and max on the dipstick
 
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Someone else confirmed what I had said that 5.5 litres takes it between min and max on the dipstick

That was me.

There's no question that if you put the book figure of 5.5 L into my M271 it doesn't come anywhere near max on the dipstick, in fact not even half way between min and max. I've changed the oil 5 times now and the results are consistently the same. 5 L takes it to min and 5.5 about 1/4 way towards max.

The book gives the volume between min and max as 2 L. That seems a lot but if accurate means it must take 6.5 to 7 L to get it to the max mark. That's something I never done though as anything above Min should be safe. One good thing about mine is there is no noticeable consumption between the oil changes I'm doing every 4000 miles which gives me confidence to run it only a little above min.
 
That was me.

There's no question that if you put the book figure of 5.5 L into my M271 it doesn't come anywhere near max on the dipstick, in fact not even half way between min and max. I've changed the oil 5 times now and the results are consistently the same. 5 L takes it to min and 5.5 about 1/4 way towards max.

The book gives the volume between min and max as 2 L. That seems a lot but if accurate means it must take 6.5 to 7 L to get it to the max mark. That's something I never done though as anything above Min should be safe. One good thing about mine is there is no noticeable consumption between the oil changes I'm doing every 4000 miles which gives me confidence to run it only a little above min.

Are you doing oil changes every 4000 miles why so often?

Do you use the mercedes 229.5 oil?

I'm planning to do an oil and filter change in Dec then will stick to yearly servicing

I've emailed MB customer services regarding the engine oil levels and whether more oil can be added to get it to the max point
 
I bought an 'oil sucker' and if I remember rightly the blurb said something like " one litre increments marked on vessel" It's one of those vertical cylindrical types and there were no markings on the cylinder walls but its plastic construction meant it had ribs around it at set intervals that some my take as being one litre marking point.

No chance, they were waaaay out. Before I used it, I filled it one measured litre at a time with coloured water (OK... it was blackcurrant squash) and used a permanent marker on the opaque plastic to mark the rising level (of now undrinkable squash) .The marks I made are nowhere near the 'ribs' that are cast into the plastic , which I believe are just for strength but some might think they are incremental markings. I took a photo, I will post it later if I still have it.
 
I bought an 'oil sucker' and if I remember rightly the blurb said something like " one litre increments marked on vessel" It's one of those vertical cylindrical types and there were no markings on the cylinder walls but its plastic construction meant it had ribs around it at set intervals that some my take as being one litre marking point.

No chance, they were waaaay out. Before I used it, I filled it one measured litre at a time with coloured water (OK... it was blackcurrant squash) and used a permanent marker on the opaque plastic to mark the rising level (of now undrinkable squash) .The marks I made are nowhere near the 'ribs' that are cast into the plastic , which I believe are just for strength but some might think they are incremental markings. I took a photo, I will post it later if I still have it.

Is that pela 6000 pump?
 

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