Turbo fail

[black r]

Hi All

Recently the turbo failed, now VW are saying that metal fragments have been found in the oil and that a new engine is required. I thought that the oil that feeds the turbo and returns to the sump is via a separate feed. Is this correct?
If there is metal fragments in the oil, wouldn't they be caught by the oil filter of oil pump before making it into the engine itself?
The car was with VW for over 2 weeks before they confirmed.

I'm not a VW/engine expert, so I'm hoping some of you may have a different opinion or have also experienced similar issues.

[Lucas_R]

The oil is plumbed under pressure to the turbo to lubricate and cool the bearings etc, then the drain is gravity fed from the bottom of the turbo back down to the sump.

Depending on the size of the metal fragments in the sump, they likely would not make it through the oil pickup (which has a type of metal mesh gauze) to prevent anything foreign getting pumped through the engine. Only very fine fine particles would get through and these should be captured by the oil filter.

Plenty of turbo's on Mk7 R's have failed in the past 3-4 years, and i do not recall anyone having to replace the engine - they have all been remove and replace turbo and do an oil change.

Perhaps its worse than how it sounds if VW are saying it needs a new engine. Personally i would get a 2nd opinion before spending a large chunk of cash that might not be necessary.

[GolfRWag]

Oil filters do not filter all oil at all times - at high revs/high oil flow volume the filter goes on bypass on most cars.
So a sump full of finer fragments may easily get circulated depending on when the turbo fails.

[Transporter]

...also, the oil filter is in a bypass every time the engine is too cold and oil is thicker resisting to flow and also when the filter is towards the end of its life, filled up with particles.

[doc_777]

Too many questions. What are the fragments? Are they bearing material from the failed turbo? Something else? A used oil analysis would quickly show what metallurgical content was in the oil - and its pretty easy from there to determine if that’s turbo bearing matter or not.

If it were mine, i’d have the engine out, valve cover and sump off and do a full clean. I certainly would not just assume that some metal fragments meant a new engine. Unless of course VW are supplying a new motor as a good will claim.

Unfortunately deep diagnostics of this type are not something most dealership mechanics are either skilled or equipped to undertake. They don’t repair, they replace.

[minke]

Impeller gets out of balance, hits the housing sending shards into the combustion chamber. That's one way to need a new donk.

[doc_777]

Impeller gets out of balance, hits the housing sending shards into the combustion chamber. That's one way to need a new donk.

metal fragments in the intake should be trapped in the inter cooler - which is why some people refer to them as a ‘turbo catch can’.