I checked the engine oil level after 3K from last service (I rarely do that). It was in the middle of the dipstick marks so I added a "quarter of a quart". Finally, I ended up adding again the same quantity but the level is now over the top bulb but below the steel rod.

Should I have everything drained and filled again or I am still in the safe margin?

 

Should really be within the min & max levels. Anything outside these isn't good for the engine.

 

Disagree, just over the red bulb is fine. Much of the way up the rod then you run the risk of frothing the oil = bad.

 

Anything over the manufacturers recommended filling quantity increases internal oil pressures risking premature gasket failures.

Fill to mark and motor on.

 

Nothing I have read or been taught says overfill by a quart will damage any engine, all sumps are designed to accommodate slight overfill. Show me a technical article that says increased pressures occur from overfill? It will aeriate the oil of the crank hits it acting like a whisk.

 

Anything you have been taught? By whom ? Jiffy lube....lol. Glad you'll never be working on my MINI.

Your engine relies on consistent oil pressure to keep the moving parts running smoothly. Changes in the oil pressure and overall lubrication of the engine can lead to:

• Engine damage such as bent rods in the engine or collapsed valve pipes.
• Catastrophic engine failure where the engine sustains enough damage that it cannot be repaired, but must instead be replaced.
• Excess engine wear from inconsistent oil pressure over time.
• Spark plug fouling, resulting in the need to replace spark plugs more frequently.
• Excess oil deposits in the catalytic converter.

 

When too much oil is poured into the reservoir, the excess oil can be pulled into the crankshaft as it spins. The oil is mixed with air and aerates the oil and will decrease the oil at pick up location for pump. The end result is damaged engine. 1/2 qt will probably do nothing....anything more than that your taking your chances and a full quart over - you need to drain the excess.

 

Amazing how many people think they are smarter than the engineers and designers of things like engines.....The fill limit is the limit. Wanna be a test pilot, go ahead. Telling someone else how to be like you and irresponsible at engine maintenance...just plain arrogant. This kind of talk reminds me of college days when they talked about the Dunning-Kruger effect.

 

Had my oil changed 3 weeks ago and they overfilled significantly, maybe an inch above max fill line, but I didn't know until the exhaust started smoking after reaching operating temperature. I had a plume of smoke shooting out after every stoplight, I looked like an octopus shooting ink.

I finally took it back last week and they drained and refilled. Everything is back to normal.

As for the OP, if your exhaust is smoking, bring it back ASAP. Otherwise you're fine.

 

At first, I shouldn't even have added oil because it was within recommended level by the manufacturer. What is the oil quantity between the lower and top red bulb on the N18 engine since the dipstick is different from the N14? I would bet it is about 1/2 quart.

 

As you and I have both stated, just at the top of the bulb (around a 1/4 of a quart) is not overfil. There is no arrogance in my posts. We are saying the same thing except there is no evidence that it will over pressure or blow anything. The outcome of aeriated oil is poor lubrication and high engine temperatures damaging the moving parts/cams/crank, etc and premature engine failure so again we both agree overfil is a terrible thing. If anything aeriated oil will produce lower pressure due to the effect on the oil pump trying to push froth around the engine pathways and galleries.
No arrogance intended, I simply disagreed that a 1/4 of a quart is not dangerous and any more than that is but you went off one one... keep the rage for home, not on a helpful forum.