Squeal Noise thru turbo - Excessive clearance or what

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Originally Posted by growler2058

If its an exhaust leak or a turbo flange leak the tell tale sign of soot is what to look for. Mine was the same but the noise went away when the motor heated up. I had snapped a stud the first time. Second time round was due to the #$@* who fixed it the first time being a dodgy bastard resulting in me getting all faces of the exhaust manifold and turbo machined again and correct studs put in

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Good move to replace exhaust manifold stud when they look at all suspect (good advice).

Crawling all over it, no soot marks yet but could be hiding. My noise is present when engine is hot or cold, that is why I started looking at turbo. Noticed the comp wheel bearing play and saw that the comp wheel can touch housing.
Noise occurs at faster spool, that equals more load on turbine wheel so more misalignment of the shaft in the bearings and could cause the excessive misalignment hence the noise. Could have over revved the wheel shaft as running 21psi boost.

To hedge my bets, unless a leak is found, looking at upgrading the turbo and the air flow ducting.