Overfilling oil

[Nads02]

Had a call today from a driving instructor who decided to 'top up' oil before going back to work. He filled up 5 litres of oil because he noticed an oil leak and asked me if I can remove the excess oil. Charged him £10 to remove the oil (reasonable imo) and no word of a lie I got over 9 litres of oil out of his 1.6 a3. There was still oil left inside the engine but it was then between min and max on the dipstick. So I topped it to the correct level. However now his petrol 1.6 engine sounds like a diesel, knocking and rattling, even stalled itself once. Sounds like it's misfiring. How much of a disaster is he in? And how do mechanics get around this problem because I've done this honestly and tried to be as fair and transparent as possible but that won't stop people blaming me for their engine going bust when it wasn't me

[GreenV8S]

Nads02 said:

Had a call today from a driving instructor who decided to 'top up' oil before going back to work. He filled up 5 litres of oil because he noticed an oil leak and asked me if I can remove the excess oil. Charged him £10 to remove the oil (reasonable imo) and no word of a lie I got over 9 litres of oil out of his 1.6 a3. There was still oil left inside the engine but it was then between min and max on the dipstick. So I topped it to the correct level. However now his petrol 1.6 engine sounds like a diesel, knocking and rattling, even stalled itself once. Sounds like it's misfiring. How much of a disaster is he in? And how do mechanics get around this problem because I've done this honestly and tried to be as fair and transparent as possible but that won't stop people blaming me for their engine going bust when it wasn't me

If it has been overfilled by 5L and you then took 9L out, you should have put at least 4L back to return it to the original level, plus whatever topping up it actually needed. How much did you put back? If you left the oil level way too low this could have caused oil starvation leading to all sorts of damage.

[Nads02]

Not too sure how much oil I topped up, there was more than 9 litres in the car before i started working but I triple checked and made sure it was on the max mark. But the engine is goosed, told him he'll have to take it to a garage as he's probably caused big engine damage

[Djtemeka]

I did similar to my mums renault 9 st box back in the day. It burnt 1L oil a week so on payday I put 5L in to see me through the month. Started ok then half a mile down the high st it was strugling and the traffic couldn't pass me due to the atomic cloud behind me
Got it home where my step dad gave me a bking then we drained it and that rat of a car kept going !

[hman]

Could have partially hydro locked the engine with that amount of oil - pistons could have literally hit the oil as the sump would have been so full, bent rods, piston damage, ring damage - god knows until you get the fault codes.

[Nads02]

hman said:

Could have partially hydro locked the engine with that amount of oil - pistons could have literally hit the oil as the sump would have been so full, bent rods, piston damage, ring damage - god knows until you get the fault codes.

Esp light and engine light came on. Have no idea why the esp light is on but the engine light isn't surprising. The car did sound like it had rod knock from the passenger side of the engine and the car was shaking on idle. I don't think I'll ever understand why he did that, but could've been worse

[Drogo]

Tell him he also needs to hand back his " Instructor" licence.

[Nads02]

Drogo said:

Tell him he also needs to hand back his " Instructor" licence.

Was thinking that myself haha. Luckily it's his secondary car, an auto 2006 a3. Still gonna be worth money though but luckily not mega expensive

[Hereward]

Can't be good for the oxygen sensor and catalytic converter.

[thebraketester]

That is impressively dim of him... I imagine the max. cap. is around 5L on that engine.

[steveo3002]

did he run it with the extra oil ?

[Nads02]

steveo3002 said:

did he run it with the extra oil ?

Yep. I first arrived thinking it's a self service that went slightly wrong but was quite shocked when I found out that the car was driven.

[steveo3002]

could have a look at the plugs , possibly oily and need a clean up although good chance its bent something expensive with that amount in there

[Sheepshanks]

Nads02 said:

Had a call today from a driving instructor who decided to 'top up' oil before going back to work. He filled up 5 litres of oil because he noticed an oil leak and asked me if I can remove the excess oil. Charged him £10 to remove the oil (reasonable imo) and no word of a lie I got over 9 litres of oil out of his 1.6 a3. There was still oil left inside the engine but it was then between min and max on the dipstick. So I topped it to the correct level. However now his petrol 1.6 engine sounds like a diesel, knocking and rattling, even stalled itself once. Sounds like it's misfiring. How much of a disaster is he in? And how do mechanics get around this problem because I've done this honestly and tried to be as fair and transparent as possible but that won't stop people blaming me for their engine going bust when it wasn't me

I'm confused by your involvement in this - are you a mechanic?

[Nads02]

thebraketester said:

That is impressively dim of him... I imagine the max. cap. is around 5L on that engine.

Tbh I wasn't sure the max capacity but I removed the oil until the reading was somewhere in the middle, then topped it up a little at a time until max reading was met

[Nads02]

Sheepshanks said:

I'm confused by your involvement in this - are you a mechanic?

I'm training to be a mechanic at the moment but do odd jobs here and there. He's the friend of my driving instructor (they're both instructors)