Engine Oil Level

[kalacoconut]

I had my C200 (petrol) serviced recently. After leaving the engine to cool down & let the oil drain to the bottom of the sump (more than 6 hours), the oil level is now 4mm-5mm ABOVE the maximum mark.
I am under the impression that this might damage the catalytic convertor. Is this true for a 4mm-5mm overfill, & should I ask the garage to remove some? The garage says 4-5mm is not too much overfill to cause any damage.
Also, if I should have some removed, is it better to siphone it or should it be drained or doesn't it matter?

 

[BlackC55]

Dip it after 5 mins and this is the correct level (when hot)

If it is over the max then, it will need to be corrected.

Too much is almost as bad as too little.

 

[Myros]

in short, it's too much

you need to suck some out. 4 or 5 mm may be as much as a litre, if you work on the calibration of the dipstick ( 2litres between top and bottom marks approx.) I think MB say test the level with the oil hot, as this is the way it spends it's working life. That way, the oilways are coated, and the oil has expanded to it's "true" volume. That's what's going to cause the damage, if you see my drift.

 

[kalacoconut]

Thanks guys. I'll have a look when the oil is warm, but I think the level is very close to the MAX indicator if I check it within a few mins of switching the engine off. I'm under the impression that the level goes up with time as the oil eventually drains to the sump. Is it easy to suck the oil out myself by sticking a tube down the dip stick well?

 

[Myros]

I have one of the commercial oil syphon devices

it cost me about £12 at the local marina. You can get them from Machine mart and such like. Or cobble something out of a suitable bit of tubing and an empty washing up liquid bottle if just for a one off. Just like blue peter.

 

[frank133]

Hi to be honest if you have paid for a service and you think the oil level is to high,take it back to the garage,it will take them a few minutes to sort it out. they should also apologize for their mistake.

 

[television]

Hi to be honest if you have paid for a service and you think the oil level is to high,take it back to the garage,it will take them a few minutes to sort it out. they should also apologize for their mistake.

I have to agree with you Frank

 

[David Nock]

I have had this with a dealer a few years ago. There should be no overfill.If the garage argues show them:- 1) the handbook and 2 ) the filler cap. Both warned at the time against overfilling on a C class. The dealer couldn't argue against MB's own technical advice. Make 'em take it out.

 

[David Nock]

What's worse is the conjecture as to how it's happened. They've sucked out the old but not got it all. Then they've put in the correct amount of new!!

 

[rf065]

When a workmates son went on holiday last year, he left his Audi A3 for him to use for two weeks, rather than have it sitting there not being used. His parting words were, it needs the oil topped up dad. He duly topped up the oil and the car broke down after half a mile the first time he used it.

The Audi dealers came and collected it, and reported back that it had been overfilled with oil. He was told that apparently modern engines have sealed crankcases/engines and excess oil over pressurises the engine causing extreme damage. He was looking at a bill of £1600 to repair the car.

Being a miserable sod, he left it for his son to deal with and did not pay a penny towards the repairs, refusing to admit he was responsable. As he admitted topping up the oil, I can imagine his son was not amused with this stance. Only he knows how much he put in, so in your case, do you feel lucky...........................................................................................

Seriously though, if you check the oil a few minutes after switching off, it will probably be around the correct level or within 1 or 2mm, I don't think that would be worth worrying about.

Russ

 

[jtripp]

If you are using a synthetic oil such as Mobil 1 you might need an overnight draindown to see the actual oil level reading. Also Mercedes recommends wiping the dipstick and leaving it in the tube at least 3 minutes. There is a very tiny air bleed hole, smaller than a #60 drill just below where the dipstick tube enters the crankcase. This is there to vent the pressure in the tube caused by the O ring seal at the top of the dipstick. When you push the dipstick the last 1/2" it acts like a piston and would push the oil out of the dipstick tube at the bottom and give a false reading. Clever, eh wot!

This is a hot topic in the Mercedes club of America.

 

[rf065]

If you are using a synthetic oil such as Mobil 1 you might need an overnight draindown to see the actual oil level reading. Also Mercedes recommends wiping the dipstick and leaving it in the tube at least 3 minutes. There is a very tiny air bleed hole, smaller than a #60 drill just below where the dipstick tube enters the crankcase. This is there to vent the pressure in the tube caused by the O ring seal at the top of the dipstick. When you push the dipstick the last 1/2" it acts like a piston and would push the oil out of the dipstick tube at the bottom and give a false reading. Clever, eh wot!

This is a hot topic in the Mercedes club of America.

If Mobil 1 is recommended by Mercedes for my car (which it is), then why should I have to wait overnight to get the correct oil level. Where exactly in the handbook does it tell me to park the car on level ground and if you use Mobil One, wait until the next morning before you can check the oil level?
Don't take this the wrong way, but I'm just back from the pub, and in the cold light of day, the second point about vents in the dipstick is probably pish too.

I work in the gas industry & deal with pressure everyday, have you any idea how much increase in pressure a rubber o ring on a dipstick can impact on the inside of a sealed engine? Is there an instrument that small and accurate that could measure this?

Again, no offence, but this sounds pure bull****, until someone can prove otherwise.

Russ (half pished & off to bed)

 

[Parrot of Doom]

If such a thing really happened I think Mercedes would just recalibrate the markings on the dipstick, rather than ask people to wait for 3 minutes.

 

[BlackC55]

If Mobil 1 is recommended by Mercedes for my car (which it is), then why should I have to wait overnight to get the correct oil level. Where exactly in the handbook does it tell me to park the car on level ground and if you use Mobil One, wait until the next morning before you can check the oil level?
Don't take this the wrong way, but I'm just back from the pub, and in the cold light of day, the second point about vents in the dipstick is probably pish too.

I work in the gas industry & deal with pressure everyday, have you any idea how much increase in pressure a rubber o ring on a dipstick can impact on the inside of a sealed engine? Is there an instrument that small and accurate that could measure this?

Again, no offence, but this sounds pure bull****, until someone can prove otherwise.

Russ (half pished & off to bed)

Seconded!!!!!!

 

[wireman]

If the dipstick tube lower end is immersed in the sump oil at its bottom end the scenario you describe is perfectly feasible, and any simple water manometer will measure the pressure increase. I have used dip leg systems of this style to accuratly measure process fluid levels on chemical plant and it is very reliable, the pressures on our plant were in the range of 0.1- 50 inches water gauge. there are plenty of instruments that can accuratly measure these low differential pressures.

 

[kalacoconut]

Thank you all for your responses - much appreciated. I'll get the garage to drain some out.

 

[jamesmc]

Here is a suggestion.

If anyone feels that Mercedes may have got wrong, and have any doubt about how reliable the reading is on the original dipstick, why not make up a new 'dipstick' from wire.. (straightened coat hanger maybe) and mark it to the length the Mercedes supplied dipstick functions at when fully inserted. Dip the oil and compare the result to the original dipstick. No 'O' ring there, so no 'potential' back pressure in the tube either.

You might be inclined to loop the top so that it doesn't accidentally drop down the tube

My car is 8 years old... it's still running fine. I'm sure the dipstick is doing it's job.

 

[television]

The level cant be that critical for I would have problems on my driveway that is very steep 25 degrees to be exact,add that to the braking effect and if it was this critical the my cats should have filled up years ago

 

[jtripp]

To: Rf065 and BlackC55 - The 2 doubting Thomases:

If you are using synthetic oil please check your oil level first thing in the AM after an all night cooldown and then check it when hot and see if there is any difference.

As for the vent hole, actually I found a second vent hole opposite the first one. I hope that the picture gets through.

I may be new to your forum but you can check my profile out at the following:
http://mbca.cartama.net/member.php?find=lastposter&t=21643 My member name is jtripp.

Apologies cheerfully accepted !

 

[jtripp]

Additional information

The top of the dipstick tube has an inside diameter about 5/8" and is 3/4" long below the upper vent hole. Just imagine the pressure developed by the bore and stroke of the top of the dipstick pushing the oil down the tube and giving a false reading if there were no vent holes in the tube above the oil level. The dipstick tube is for a"99 E300 Turbodiesel.