Oh-oh: too much oil?

[socratic]

I had a local shop (not dealer) change the oil and filter. He might have overfilled it.

He was very conscientious and filled it with only 8 litres to begin with; saying that the preferred to do that, start the engine, let the oil filter fill up and then measure and top up. After I started it up after 8 litres the electronic gauge was only 2 bars above the minimum line.

So he added more, this time relying solely on the dipstick. He kept filling and measuring and he went past 9 litres. It was nicely topped up to the top of the dipstick measurement (he showed me because I was watching nearby).

This morning with the engine cold, the electronic gauge showed 1 bar OVER the MAX fill line. And the dipstick showed almost the whole red plastic thing covered in oil.

Am I in trouble now? Should I get him to drain out 1/2 a litre?

MNBoxster, whose opinion on this forum I trust, has said that my catalytic converter could be at risk.

The only thing I could think of that went awry was that he was filling and then measuring quite quickly, thus not letting the oil drain all the way into the pan.

Any advice would be welcome.