Can a turbocharger be fubar'd by overfilling the engine oil?

[GavinPearson]

There are lots of engines that 'make oil' when the injectors fail by over delivering the fuel, in turn have it wash past the rings and raise the oil level in the sump.

The same can happen in engines where the fuel injection connections are under the rocker covers and fail.

Once the oil level gets high enough the crankshaft whips the oil and it gets drawn into the breather system.

The turbo ingests the oil and it gets sent to the intercooler.

Once the engine reaches enough speed to have the fuel stream drawn into the air it will burn hot enough to melt pistons and often the evidence of the injector issue is missed due to other damage or overlooking it during teardown.

If a stream of hydrocarbons with uncontrolled metering is present for long enough then the engine could run away, quite possible when the crankcase is overfilled. But again, did it get there because the engine made oil, or because of a maintenance misstep?

Personally I would have the garage verify that the injectors were all perfect and the fuel delivery system was perfect before accepting that the engine failed due to oil overfilling.

[Kitchski]

Report stated no sign of contamination in the oil.

[D_G]

The oil level was either too high or the turbo was leaking into the intake otherwise it wouldn't have run away. If it was the turbo seals you would have put in a lot of oil (probably a few litres) before the oil reached a level to be sucked in causing the runaway. The other likely cause was the car was filling the sump with diesel either through injector leakage or by constant DPF regeneration, in this case the oil level would gradually increase until it is sucked in through the breather system.
It's becoming a common issue now with common rail diesels, Joe Public doesn't realise what's happening until it's too late.

[GavinPearson]

Kitchski said:

Report stated no sign of contamination in the oil.

Was the oil analysed by an oil analysis company or a mechanic / technician / "engineer".

A good company can measure the viscosity and determine what oil fractions are present and what level of lubricant pack is present, i.e. precisely what did your sump have in it?

If it had a lot of additive then it was simply overfilled with oil.

If it was low viscosity and had a heavy level of dilution of additive it was almost certainly oil dilution.

[New POD]

Kitchski said:

The car was covered by warranty and the garage proceeded to change the engine etc....a bill of some £3k or so in total.

Fast forward to today....warranty claim has been rejected as they are claiming the damage was caused by overfilling the engine with oil

I'm sorry, they have the work done, without knowing if it will be covered by the warranty? Or were they told it would be covered by the warranty before the work was done ? In which case.....