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Subject Failed Turbo Analysis (long with pics)
     
Posted by OverZealous (CT) on May 16, 2014 at 8:13 PM
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Message I wasn’t able to unbolt the turbo shaft so I used a dremel wheel to cut off the nut -- thanks for the recommendation Zvil (FL). Sometimes brute force really is better. No, I did not clean the impeller after the dremeling.



This is what the compressor side looks like with the impeller removed. Pretty simple, right?

This is what the shaft looks like outside the CHRA. I was not able to get the thrust bearing out to peek inside.

There was a fair amount of black dust located under this cap located just ahead of the turbine wheel.

Here’s the back side of the compressor. Notice it’s appropriately flared towards the inside required to keep in check the large stresses of operating over 100K rpm.



Here are a couple of pics showing where inside the CHRA the step and journal bearings are located relative to the compressor and turbine wheels.

Yes, I see that the inside of the coolant chamber doesn't look very pretty but I’m not convinced that contributed to this turbo’s failure. Onto the most interesting part: a close-up look of the turbo shaft. Again, I wasn’t able to remove the thrust bearing and look inside the CHRA. I’m saving that effort for a rainy day and focusing on getting the engine back together again assuming there’s nothing fundamentally wrong with the engine itself. I have sent an oil sample off the Blackwater Labs but haven’t heard anything back from them yet.

The shaft is so small and my little point-and-shot camera isn’t capable of focusing well in this video under these stark lighting conditions but you can clearly see where the shaft has been rubbed out. I’m assuming the journal bearings inside look similarly mangled. If you can tell something beyond the obvious that I point out in this video please let me know.

Here are my previous posts and videos of the failed turbo:
Video-of-my-failed-Turbo-long-w-Pics
Blown-Turbo--1st-Engine-Pull-lots-o-pics

Onto the engine itself. You guys were right, this engine is top HEAVY! It was a real struggle to flip it over gently. And then a ton of leftover coolant went everywhere along with a little oil residual. I got the oil pan off relatively easily using a hammer and this bed frame piece I found around my basement.

The engine mounts look ok to me. I’m planning on reusing them unless I hear something from one of you smart guys highlighting the error in my ways.

Open heart surgery to check bearing health and re-glue the oil pan gasket.

Here’s a mandatory pic of the crank stamps to determine the grade of the bearings.



A picture of the connecting rod stamps for the same purpose.

Here’s something interesting. The passenger side heat shield is rusted a lot in the location where the shield and the manifold come in contact. Dissimilar metal problem? I don't know. What do you guys think?

Onto the fun stuff. NEW PARTS!



New stocker CHRAs (yawn, I know) and MSP Manifolds. Mike Smith has impressive attention to detail even in his packaging. And some new bugles to allow the turbos to breath better. Thanks Greg and Jonathan!

The new CHRAs are incredibly tight as I suppose they should be, but the difference relative to even the still working turbo is night and day. More to come. Thanks for reading -- have a great weekend!

OverZealous (CT)

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