Oil Overfill: When Is It Harmful?

Hi everyone,

After the oil change at that excellent Seat workshop, I just checked the oil level, and lo and behold - it's about 3 mm above the upper bend on the dipstick, which, according to the instructions, indicates the maximum level.

The image is not entirely clear, but I would say the level is about 5 mm too high.

What do you think - should I go there and make a scene, or should I just let it go and hope it doesn't cause any further problems?

I took the measurement with the engine warm, after approximately 40 km of driving, and then after about 30 minutes of standstill, so that all the oil should have drained back down. The car was slightly tilted during the measurement (I will repeat the measurement straight again later or tomorrow), but since the dipstick is roughly in the middle of the engine block, this shouldn't have a major impact (the tilt was from left to right, not from front to back).

Best regards,

Jan.

Hi Jan,

For example, if you consider that the gases from the pistons are pushed back and forth "above the oil level" between the individual cylinders, then an oil level that is too high creates a narrowing of the corresponding free flow area, which can result in correspondingly higher "internal pump losses" and, in some cases, a higher oil concentration in the crankcase ventilation exhaust gases.

Sooner or later, the engine will somehow get rid of the "excess."

I would personally only take the general sticker warning "Risk of cat damage" seriously when there's "way too much oil" – roughly, when the catalytic converter becomes a constant source of oil and the exhaust gases consist mostly of oil combustion residues.

If "something" being too much oil were a serious problem, considering the likely frequency of such maintenance errors (sum of private individuals + workshops!!), we would probably hear more about consequential damages, etc.

Hello Jan,

I had the exact same problem with my Seat dealership... The oil level was about 3mm above the upper bend of the dipstick. Well, the oil level hasn't changed in about 10,000 km; it was obviously not enough oil to be "pushed out" as Ulf described.

I've had good experiences with oil changes at ATU: the mechanics filled it, checked the level, maintained everything, added a little more, and then checked the level again until the oil level was correct. In a regular workshop, they probably just pour in a defined amount of oil and hope that everything has drained out beforehand.

Best regards, Georg.

Hi everyone,

That certainly puts my mind at ease a bit.

I checked the car again a little while ago while it was still parked, but it was noticeably colder then, and it had just been running for a short time, so it was right at the top edge of the ribbed area, even a bit lower than "too much." I'll check it again tomorrow after driving about 10 km and letting it sit for a short while. If it's not too extreme, I'll just leave it.

While I was waiting today, the car was stuck for almost 30 minutes, so it must have been a combination of several factors. I doubt anyone usually waits that long.

I'm not as worried about the catalytic converter... I think that diesel catalytic converters are much less susceptible to theft than those from gasoline cars. What do you think?

Best regards.

Jan.

Hi Jan,

When I went to the VW dealership for the first few times, they also put in too much oil. Even a significant amount too much. (That's one of the reasons why I don't go to VW anymore!)

Passiert ist aber zum Glück nichts. Ist mit der Zeit dann einfach weniger geworden. Ich weiß halt nicht in wie weit das mit meinem Simmerring an der Kupplung zusammenhängen kann, da der dann irgendwann angefangen hat Öl zu lassen. Naja. }

Greetings,
Thomas.

Hey fellow mechanics,

ich habe dazu noch die folgende Geschichte eines Bekannten anzubieten. Er fährt einen SEAT AROSA Benziner. Das Auto wird nicht nur von ihm genutzt, sondern auch noch von ein paar Freuen (ich hab wirklich nix gegen Frauen) in der Familie. Irgendwann war es mal soweit, daß der Wagen zum Ölservice wollte und im Display beim Tacho nur das Wort OEL oder so ähnlich stand. Und da gerade eine zweibeinige mit dem Wagen unterwegs war, hat sie an der nächsten Tanke pflichbewust eine Büchse ÖL gekauft und in den Motor gefüllt. FATAL ERROR.
The final verdict: faulty oil pump, blown head gasket, and defective hydraulic lifters.
Now I'm wondering how that could even happen?! I can understand having too little oil, but too much? And then with such consequences right away?

Here's a second story: At my civilian service placement (a specialized hospital with an attached farm), a fellow civilian service worker (a high school graduate) was tasked with refueling the tractor (a Deutz Fahr). Without thinking too much, he opened the first cap he found and poured diesel directly into the engine block. Surprisingly, only about 12 liters fit in there. So, he continued searching and eventually found the actual fuel tank cap and refueled it properly.
Of course, he drove the tractor into the barn and parked it without saying anything.
The next morning, the gardener drove the tractor, and he immediately noticed something was wrong because oil was leaking from all the openings.
An oil change was then performed immediately. It's been 5 years since then, and the tractor is still running without any problems today.

What can we learn from this? Things always turn out differently than you expect...
Regards,

Eike.

Hi,

It really surprises me. A friend of mine who works in a garage once told me about a time he was called out to a woman's house because her car wouldn't start. Apparently, she had completely filled the engine with oil.
She probably meant that she knows about it from the gas station.
Well, there are probably more heroes like that out there.
(I have nothing against women. After all, there are also men who can't tell the difference between a diesel and a gasoline engine, or who don't know that a TDI doesn't have a lambda sensor ).

See you later.
Thomas.

or not know that a TDI doesn't have a lambda sensor ).


I would be careful about that now .

http://www.kfztech.de/kfztechnik/motor/diesel/DieselAbgas.htm

CU Gremlin.

Hi,

Did you read that in the thread about the fuel injectors?
I'd be curious to know.

@ Georg and Rainer.
Tell me what you think!

See you later.
Thomas.

Hello Gremlin,


Hmm... I can't find any information on the use of lambda sensors in future diesel engines on the page you provided. Or do I need to follow another link?
I once read a paper online that suggested lambda sensors could be used to reduce harmful emissions.
I'm quite interested in this topic, do you know any more about it?

Best regards, Georg.

Hello Georg,

Please take a look at the pictures under the "NOX Storage" category!

http://www.kfztech.de/images/kfztechnik/diesel/abgasregen2.jpg

Hi everyone,

So, I also read in a report by BOSCH in a specialist magazine that a type of lambda sensor is supposed to be used in future diesel engines. The reason is that this is the only way to accurately monitor and control the combustion process in the cylinders. It actually sounds logical.

Regards,
Eike.

As Bertil already wrote:

This becomes relevant in conjunction with NOx storage catalysts. Additionally, a urea-based system is currently under development.

The EDC16 is fundamentally capable of controlling a catalytic converter or a particulate filter; it's just a matter of time.

CU Gremlin.