Oil level help

Discussion in 'Parts, Maintenance & Servicing' started by Sean2e0saf, Aug 24, 2017.

  1. Sean2e0saf

    Sean2e0saf Active Member

    Messages:
    73
    Joined:
    Feb 12, 2017
    Car:
    C220 w204
    2007 w204 220

    When engine cold where should the oil level be on dipstick..

    I have always been taught at max fill level

    However

    A local independent Merc specialist said just over half... seems low to me

    He said it allows for the oil pressure to rise when warm and at higher motorway speeds..!!

    Any help plz
     
  2. grober

    grober MB Master

    Messages:
    27,924
    Joined:
    Jun 22, 2003
    Location:
    Perth, Scotland
    Car:
    W204 C200CDI Estate
    He's right. Oil expands as it gets hot so the level rises on the dipstick. IRRC the difference between fill and full marks is around 2 litres on the OM651 engine. When changing the oil there is usually around a litre left in the various oilways meaning if the oil is refilled using the official capacity- its slightly overfilled. An overfilled sump may allow the crankshaft to hit the oil in the sump causing aeration of the oil potentially starving the engine of oil- it may also increase sump pressure forcing oil vapour into areas it shouldn't clogging them up and contaminating exhaust emission cleanup devices. - not a good idea! I like to see at least a 5mm gap between the top of the oil and the full level on the dipstick when the oil is HOT so I guess this would translate to
    1/2 to 2/3 full when COLD.
     
  3. MancMike

    MancMike New Member

    Messages:
    0
    Joined:
    Jul 29, 2014
    Yes, you're supposed to run the engine to temperature, then park up on flat ground, stop engine, wait 5 minutes, then check.

    Checking when cold is pointless because everything expands when heated, so you want to check when it's hot, to know it's not overfilled.
     
  4. rf065

    rf065 MB Enthusiast

    Messages:
    4,117
    Joined:
    Jun 8, 2007
    Location:
    Grossbritannien
    Car:
    SLC300 - C250d Estate 4 Matic & Z900rs
    Make up your own mind on this, I do the opposite of the advice given already.
    On my CLK, I always check after it has been sitting overnight and make sure it is filled to the full level when cold.
    It's now almost 12 years old, 135,000 miles, doesn't burn oil or suffer from any engine or oil related problems. Only thing I insist on is using Mobil 1 & changing it midway between each service too.

    Russ
     
  5. 190

    190 MB Enthusiast

    Messages:
    3,155
    Joined:
    Mar 4, 2015
    Location:
    Cheshire
    Car:
    2009 W204 C180K
    Although I too was a fill to Max devote there is no magic or real benefit from doing that. MB are happy for you to run anywhere been min and max and the engine will be safe. There are only two variables to bear in mind other wise run it where ever you want:

    When running at max it will take a little longer for the oil to reach optimum operating temperature which is not good if the car is routinely short tripped.

    If the oil is being run on long drain intervals, say 12-15000 miles then running at min risks using up the oil additives.

    I would never fill to max with the oil cold. If the oil is going to be checked cold I'd fill to no more than 3/4.

    What I do is personally is run at 1/4 above min and change the oil annually at 5000 miles. To fill to max in those circumstances would simply be to waste oil.
     
  6. optimusprime

    optimusprime MB Enthusiast

    Messages:
    3,265
    Joined:
    Dec 29, 2013
    Location:
    Kidderminster Worcestershire UK
    Car:
    Mercedes W124 260E M103
    To check the level the engine needs to be cold .If checked hot, lots of oil will still be in the oilways of the engine and valve covers .Waiting for it go cold , by then , the oil will have made its way back down to the sump. The idea of half way on the dipstick is a good way to go. A maximum mark on the dipstick means just that, you can keep it on the max mark if you want to . You get a service from M/B it will come home on the full mark ,or maximum .Ans some times over filled , so check it on return from the service.
     
  7. Marku

    Marku Active Member

    Messages:
    764
    Joined:
    Dec 18, 2012
    Car:
    Viano Ambiente 2.2CDI W639, S-Class 450SE W116
    Preparing for a long trip I checked the oil level and topped it up to the full mark. On then driving away, not far, the display told me that it was over full and should be drained or risk damage to the engine. Took it to the MB dealer who very kindly, and for free, did it without delay. I asked them about the display and was told that the sensors are too sensitive and generally they fill them no more that 3/4. Some time later collecting it after a service I got about 10 miles and the display was telling me too little oil add 1 litre. Took it back and got profuse apologies and they topped it up. I always get charged for 9 litres which is the stated maximum capacity. Must remember to check the oil immediately after a service just to see how much actually gets put in.
     
  8. rf065

    rf065 MB Enthusiast

    Messages:
    4,117
    Joined:
    Jun 8, 2007
    Location:
    Grossbritannien
    Car:
    SLC300 - C250d Estate 4 Matic & Z900rs
    They also aren't accurate & shouldn't be taken as gospel.
    I've experimented with mine, every time I've drained the oil the sensor never reads below 1.4 litres when empty. When filling up to the 6.8 litres my CLK holds, no matter how much oil you pour in, it never reads above 6.4 litres.

    I no longer pay any attention to it & rely on a dipstick which is always 100% accurate.

    Russ
     
Tags:

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.