I have never heard of a turbo failing that way. I.E. the turbine

separating from the shaft.

I wonder what the history is of that turbo. Then again I have zero

experience with

turbos. IMHO most of the failed turbo's I have seen due to excess heat

have melted blades.

Francois has many hours on the dyno using that turbo and rates his engine

at 230 HP.

Obviously with a bit of boost.

Paul Lamar

Archie wrote:

Ditto here, Paul
However, at one time was involved in some fixturing for these,
and since the turbine is friction welded to the shaft, I wonder if
the weld was internally defective?
Archie

I am sure it is not a new turbo so it is strange that it failed so soon.
Perhaps the turbo thrust bearing went out... the turbine jammed in the housing
while at high RPM and the rotational inertia of the compressor wheel sheared
the turbine from the shaft. That is about the only explanation I can come up
with now.

Paul Lamar

I just thought of another possible scenario. Somebody might have attempted to "overhaul"
it by cutting off the the original turbine and welding on another relatively good
used turbine.

Paul Lamar

I had a failure once where the outer oil seal leaked oil into the exhaust stream -- crystalization accumulated in the form of a steadily growing pyramid until finally it became high enough to interfere with and stop the turbine.  In the case shown here, it is conceivable that such a buildup occurred, broke off in a large chunk with the turbine at high rpms, causing the failure.  Pure speculation----

Bob

 
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