Turbocharger Oil Starvation Failure Analysis (3540/76)

[RaceEquipped]

GT3540/76 Oil Starvation Failure Analysis

Through my vast experience in Turbocharger modification and servicing, I have come across my fair share of failures, from minor noisy bearing failures to completely nuked turbochargers.
A good 80% of them are oil related, especially when it comes to GT3540/GT3576 Falcon series turbochargers through oil feed line filter blockages and dirty oil supplies.

We're going to breakdown various parts of a blown turbo (GT3540) to analyse and identify parts that are damaged, worn and brand new. A similar process that we follow at RaceEquipped.
This turbocharger is a extreme case, as it is completely NUKED in every way and form. When disassembled we found ONE remaining ball bearing within the cage (Most Garrett ball bearing turbos have 14-16 balls within the casing) safe to say they all are sitting at the bottom of someone's sump.

Bearing Casing

The bearing casing is the first point of contact for bearing health when disassembled.
From Left to right, we have a Brand New Casing, Used casing, Used casing passed its service schedule, and last is a nuked turbo bearing casing.
The colour change from the shiny new to a dark colour is vanished oil, the ideal used bearing casing is the second from the left, this vehicle has kept oil and filter changes regular. Other variables are also involved in oil varnishing from Exhaust temps to Oil grades and thicknesses.
The last casing has been nuked, the bearing race has melted and no longer exists.

Bearing Cage

The bearing cage which holds the balls that rotate within the casing can show signs of wear also, being made from plastic they don’t like high temperatures & lack of oil. Here we can see what used to be a yellow bearing cage that has been cooked and warped. These bearing cages can also be ripped to shreds. Bearing cage and the bearing race health are consistent with the amount of“shaft play.

Exhaust Seal Seats

Now exhaust seal wear is inevitable, and we opt to NEVER reuse them even if they look healthy. But the seats for the seals in the CHRA can be damaged through excess bearing wear, or catastrophic failure, here we demonstrate the difference between a used CHRA and a sheared exhaust seal seat through the ring gap.

Internal Inspection

These photos speak for themselves, this side of the CHRA is prone to oil vanishing and is hard to avoid as it has no direct constant oil feed to offset the oil sitting to bake. In this case one is clean and one has shavings all through it, and chunks of bearings, bearing casings and what ever else has been sheared off.

Turbine Shaft Inspection

As above, exhaust seal wear is inevitable, in some cases the seal can fuse to the shaft through excess exhaust temps or oil starvation. Bluing of the turbine shaft also results from excess heat through in rare cases tuning, but is generally consistent with oil starvation. Here shows a used turbine and our nuked GT3540 Turbine where the whole lower section is fused and is unrecognisable.

Conclusion

These are a few of the following processes in our turbo health inspection test that is part of our rebuilds. In conclusion oil plays a MAJOR role in turbocharger health, to avoid these issues it must be recognized that the importance of Regular Oil & Filter Changes in ALL turbocharged vehicles.

Im especially fussy on this, that ALL turbocharged vehicles should be serviced every 5000KM.
The Ford Falcon Oil feed line oil filter MUST and SHOULD be replaced with a genuine item every service interval. A oil feed filter is a great assurance against dirty oil supplies, but can be a double edged knife in the sense that it can also be the demise of your turbo if not properly maintained. 99.9% of after market turbochargers that require the removal of the factory oil line filter is using a after-market bush bearing core. In essence a Failure to do the above steps can and will cause oil starvation and can extend the life of your turbo.

- Nick

Edited 06/01/16 11:16 AM by RaceEquipped

[turbotrana]

Keep the articles coming. Gives confidence in you and your business.

[arronm]

If the turbo oil filter was in a more accessible location it would be changed more often. But after the car has travelled 3-5000ks from new the turbo filter will have done it's intended job and can be removed and discarded. As the oil passes through the main engine filter before it reaches the turbo no additional filtering is required. But for piece of mind and in the event of a malfunction the earls kits offer some degree of protection

[RaceEquipped]

Keep the articles coming. Gives confidence in you and your business.

Thank You! Planning on making a few other in the future.

If the turbo oil filter was in a more accessible location it would be changed more often. But after the car has travelled 3-5000ks from new the turbo filter will have done it's intended job and can be removed and discarded. As the oil passes through the main engine filter before it reaches the turbo no additional filtering is required. But for piece of mind and in the event of a malfunction the earls kits offer some degree of protection

Okay out of interest is that what Ford recommends?

yeh I can agree with that, they arent always essential but does offer a good degree of protection!

[Ralph Wiggum]

I'm not sure they provide any real protection at all. In the event of an engine failure that is bad enough to block the screen it's likely particles small enough to damage the turbo will pass through the screen before the larger bits block the screen and starve the Turbo anyway. Most of the screen and 50 to 70 micron so not really much more than rock sieves.

[Skids4kids]

I use the Speedflow 10 micron filter on mine fwiw.

[Ralph Wiggum]

and how many micron is your engine oil filter?

[arronm]

20 -30

But filters are rated at an efficiency for a particular micron size. Say 10 micron and above 90%

Edited 08/01/16 01:44 AM by arronm

[RaceEquipped]

I'm not sure they provide any real protection at all. In the event of an engine failure that is bad enough to block the screen it's likely particles small enough to damage the turbo will pass through the screen before the larger bits block the screen and starve the Turbo anyway. Most of the screen and 50 to 70 micron so not really much more than rock sieves.

That's true! 100% a double edged sword the good ol oil line filter is.

Sent from my HTC_0P6B6 using Tapatalk

[Ralph Wiggum]

I've also seen turbo fail post stock screen removal due to oil coking in the right angle bend in the oil above the exhaust manifold on B series cars.

Prevention is better than cure, let the car idle down, run quality oil and change it often.