Originally Posted by
mr_matt
Yes I can see this, but in my experience anything gummy in the bearings gets washed away pretty quick. The OP says he was getting it on every start up.
What I HAVE seen is distortions in the rear bearing housings, EGV, etc or of course some schmutz that gets on the ring and starts to transfer metal from the turbine blade to the EGV ring, that gets worse and worse. These caused flames on start up.
That could be the case.. but I'm seeing it more often with my friends engines and certain brand oil. after using X brand now they can't start the turbine without turning the compressor by hand before flight.