Dipstick Troubles.

[Crustyclam]

Hi,

Is it just me that struggles to accurately gauge the oil level on the dipstick?

Checked my oil don't this morning and it seemed low. It looked like it was around the black dot mark.

Kept adding a bit at time and checking, seemed to have to add a fair bit.

The problem I find is that the dipstick is fatter at the top and the bottom, and when I kept checking the thinner middle section does not seem to have even coating around it. On the last check it looks like it's now gone past max, but the middle has dry spaces.

Never struggled so much with a dipstick. Just seems a right faff.

Thanks

 

[whitenemesis]

I hope you checked the level when the engine was at operating temp?

 

[Smart320]

Do not add any more

 

[Smart320]

Oops, fail! as previously posted should be checked after ( think after 5 mins standing from stop ) engine at full operating temp.

 

[Crustyclam]

No completely cold. is that wrong?

I find the manual is not specific enough. It says 5 mins if engine is at full operating temp, and 30 mins if not ( I took that to mean any other temp including cold)

 

[Crustyclam]

Hmmm, good job I asked here. I took the motor out for a gentle ride and got oil up to normal operating. Waited 5 mins and checked oil. It was a little past the max and this time it had an even covering of oil all over between the min and max.

Used my extractor to take a some oil out, (bit by bit, and checking each time).

Got so say though still think it's a little hard to judge, when finished I got the oil line just under the max, but that was over 3/4 of the circumference of the dipstick. 1/4 of the circumferance showed a bit over still.

Ordered a new dipstick today as well, the measuring part had a few hairline cracks on it.

 

[Petrol Pete]

Hi,

Is it just me that struggles to accurately gauge the oil level on the dipstick?

Checked my oil don't this morning and it seemed low. It looked like it was around the black dot mark.

Kept adding a bit at time and checking, seemed to have to add a fair bit.

The problem I find is that the dipstick is fatter at the top and the bottom, and when I kept checking the thinner middle section does not seem to have even coating around it. On the last check it looks like it's now gone past max, but the middle has dry spaces.

Never struggled so much with a dipstick. Just seems a right faff.

Thanks

It is a right Faff, I'm with you, I too have checked oil levels on all sorts of engines and machines and I have to say Mercedes do make it harder than most to get a consistent reading.

 

[190]

Clean oil is usually hard to read on a dipstick. Once the oil darken it's much easier. The problem I have is even when you can read the dipstick it doesn't tally with the stated capacity of 5.5.L. If I vac the oil out and then add the stated 5.5 L it doesn't even get to half way on the dipstick. So which do you trust, the dipstick or the stated 5.5 L. I decided that the pragmatic thing to do would be to run above min on the dipstick but never as high as max.

 

[Crustyclam]

Agree the pragmatic approach of midway level is best way if you check the oil regular. (I do). Amazed in the difference that cold to normal operating temp differences make in levels. Never seen such a difference on past cars.

Only owned the car since Jan, and had a full service done straight away. Straight after the oil level was near max on cold.

Always kept it same level, only needed a 1/4 litre of oil to do so since Jan.

Had some work done last week meaning new oil put in and lvl much lower hence me adding more.

 

[Crustyclam]

My last reply to the thread, but others may find it useful in the future. Last reading when warm just below max, next morning around the half way mark.

 

[Justintyme]

I always check the engine oil in my car ( 2010 E class 2.1 cdi w212, but in my opinion every other vehicle too ) first thing in the morning, and it always reads a little below the max, which is completely normal. Checking the oil level after running the engine, will always give a low oil reading as a lot of the oil will still be up around the engine, hence the dipping 1st thing in the morning before starting.

 

[whitenemesis]

Surely it depends on how the dipstick has been 'calibrated''?
If the engineer has set the level on the dipstick with a warm engine etc.. one should measure the level as directed in the handbook?

 

[219]

I have always found that , following an oil and filter change , and putting in the specified quantity of oil for oil change with filter , then running the engine briefly to fill the filter , and letting the car stand for 5-10 mins , the dipstick reading will be dead on maximum .
I’m not sure what is meant by a dipstick being ‘calibrated’ as they are all manufactured to a specific length for the particular engine model in which the correct level in the sump is known , hence , other than pressing firmly into the neck of the tube , no scope for adjustment.
Normally , I check my oil on my level driveway before starting the car , and if oil has recently been changed and filled to correct level would expect to see maximum level . On my cars the level does drop slightly between oil changes , but unless I’ve been driving particularly hard , seldom needs topped up between changes .
One thing I do use to gauge when an oil change is due is if I start to see the needle of the oil pressure gauge drop slightly at a hot idle : if it drops below 2bar/30psi ( depending on the car ) then it’s time for a change , after which it will stay pegged at max 3bar/45psi .

 

[whitenemesis]

Calibrated in as much as the min-max points will be set on the fixed length stick with the condition set by the designer.
That is, if the engineer measures the sump level on a cold engine he would etch the marks differently from those on a hot engine. There is no adjustment. (I realise this would all be calculated using computer models these days)
Thinking about the practicalities, requiring the measurement to be done on a cold engine would severely restrict when one could check levels, impossible to do mid journey.

Bottom line, just follow the instructions in the handbook!

 

[Justintyme]

I have always found that , following an oil and filter change , and putting in the specified quantity of oil for oil change with filter , then running the engine briefly to fill the filter , and letting the car stand for 5-10 mins , the dipstick reading will be dead on maximum .
I’m not sure what is meant by a dipstick being ‘calibrated’ as they are all manufactured to a specific length for the particular engine model in which the correct level in the sump is known , hence , other than pressing firmly into the neck of the tube , no scope for adjustment.
Normally , I check my oil on my level driveway before starting the car , and if oil has recently been changed and filled to correct level would expect to see maximum level . On my cars the level does drop slightly between oil changes , but unless I’ve been driving particularly hard , seldom needs topped up between changes .
One thing I do use to gauge when an oil change is due is if I start to see the needle of the oil pressure gauge drop slightly at a hot idle : if it drops below 2bar/30psi ( depending on the car ) then it’s time for a change , after which it will stay pegged at max 3bar/45psi .

Exactly Pontoneer.
Drain the engine oil while it's hot. Have the exact amount of oil ready ( Inc Filter ) Put in the oil in, and run the engine for awhile, check for leaks. If everything is Ok, stop engine and wait 15-20 mins, then check the level. At this stage, it may read a little low, because even after 15-20 mins... all the new oil may not have found it's way down into the sump after running the engine. The longer you leave it before giving it a final check, the better, that's why I always prefer to check it first thing in the morning, when the engine is cold....before starting it. I NEVER check the level in a hot engine, I have seen too many cases where an engine is checked for oil while it's hot, and ( of course ) it will read low, because of the amount of oil circulating in the upper parts of the engine. So there is an inclination to top-it up, but this is a mistake. Its not good for an engine to run with an excess of oil in the sump,,,it can and does lead to problems, and pretty big problems at that. Strange as it may seem,,,,it's better to run the engine with the oil on the lower level ( but not when its showing empty, obviously ) than have it showing higher than the MAX on the dipstick.

 

[190]

The handbook allows for your problem of oil in the the upper parts of the engine by instructing you to wait a period of time before taking a reading with the dipstick. The waiting period specified is longer if the oil is cold and shorter if hot. Taking a reading hot is therefore not precluded by the handbook.

 

[whitenemesis]

I NEVER check the level in a hot engine, I have seen too many cases where an engine is checked for oil while it's hot, and ( of course ) it will read low

But it won't read low because the measuring system has been designed to correctly indicate the level under the conditions described in the handbook As the majority of modern cars have electronic oil level measurement system now, it will only measure under the design conditions.

 

[Justintyme]

But it won't read low because the measuring system has been designed to correctly indicate the level under the conditions described in the handbook As the majority of modern cars have electronic oil level measurement system now, it will only measure under the design conditions.

For electronic oil measurement ( engines with out dipsticks) then it's clear, the system is designed to read the level correctly, hot or cold. But I am speaking about the standard dipstick, with MAX and MIN markings. I have never seen a dipstick with graduated markings which will indicate at what temp. I know that the Merc Auto transmissions have these graduated markings.. 80c and 25c and the quantity has to be in these ranges. I am not saying that the engine dipstick which will give temperature dependant reading does not exist,, just I have never come across one.

 

[whitenemesis]

I have never seen a dipstick with graduated markings which will indicate at what temp.

Neither have I, what I'm trying to explain (badly) is that the markings on the dipstick will be placed at the position to correctly identify the oil level at the temperature the engineers have stated it should be measured at?

 

[kit17]

Calibrated in as much as the min-max points will be set on the fixed length stick with the condition set by the designer.
That is, if the engineer measures the sump level on a cold engine he would etch the marks differently from those on a hot engine. There is no adjustment. (I realise this would all be calculated using computer models these days)
Thinking about the practicalities, requiring the measurement to be done on a cold engine would severely restrict when one could check levels, impossible to do mid journey.

Bottom line, just follow the instructions in the handbook!

Good advice, always go to the manual , my W205 C63 has to be done at normal operating temperature, where as other W205’s have to be done in the usual manor of waiting a set time after running or from cold.