Turbo Turbine: Replace?

lakesurfer

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Turbo Turbine: Replace?

I'm disassembling my factory Garrett TC4305 turbo for rebuild. I got the turbine shroud off and discovered that whoever balanced this last removed a crap-ton of material (IMO) from the integated shaft nut. So much, and at such angles that I really can't grip the nut (to get the compressor wheel nut off) without gouging the turbine nut. See the pictures. Is this worth saving or should I just replace this turbine/shaft assembly?

I will be having the components and CHRA balanced by a local turbo shop that comes recommended by several sources, BTW.

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ifrythings

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I had a 6.0L turbo like that, I wrapped a cloth around the turbine and held it while undo the compressor nut, it work but hurt the hand a bit.
 

icanfixall

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This appears like the hot side of the turbo.Not the aluminum inlet fan side. If so.. Then you can NEVER remove this nut. Its actually part of the hot side wheel and not a nut at all.. The shaft and hot side fan are actually cast as one piece and that will not come off the shaft no matter what you do. If your having this balanced as you posted.. Why are you trying to take it apart? These turbo shafts spin nearly 2000 rpm per second. Thats about 200,000 shaft rpm so balancing is critical.It can't be balanced in a home shop setting.
 

lakesurfer

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@icanfixall : Thanks for the questions.

you can NEVER remove this nut. Its actually part of the hot side wheel and not a nut at all.. The shaft and hot side fan are actually cast as one piece and that will not come off the shaft no matter what you do.

I understand the turbine, "nut", and shaft are all actually one piece. Used the words "nut" trying to use fewer words. Oops

Why are you trying to take it apart?

Taking it apart to replace the turbo CHRA innerds such as the journal bearings, thrust bearing, etc. Also want to inspect shaft for bluing and scoring.

balancing is critical.It can't be balanced in a home shop setting.

Agreed. Hence the local turbo shop I will use for this:

I will be having the components and CHRA balanced by a local turbo shop that comes recommended by several sources, BTW.
 

The_Josh_Bear

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Most turbine shafts look just like that, but probably less meat taken off. But that's really pretty normal from what I've seen.

Unless the shaft is out of spec or the turbine is damaged in some way there is no need to replace it. IIRC in order to check the shaft spec you need a micrometer that does .0001 resolution and same for the housing clearances but that's a different tool, cant remember what it's called.

"I will be having the components and CHRA balanced by a local turbo shop that comes recommended by several sources, BTW."

I'm no expert, but CHRA stands for "Center Housing Rotating Assembly". There's no need to have the components balanced independently then as a rotating assembly-- they are all component balanced in the first place.
Maybe that's what you meant and I'm just picking nits but thought I would mention it anyway.
 

Thewespaul

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That’s normal, although not pretty. Use a towel or vice grip if you need to get them off. The two wheels are balanced already, so make sure they are marked before removal so they are assembled back the way they were removed. If you’re getting the rotating assembly balanced then make sure to take note of the wheels orientation when you receive it
 

lakesurfer

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Most turbine shafts look just like that, but probably less meat taken off. But that's really pretty normal from what I've seen.

That’s normal, although not pretty.

@Thewespaul
@The_Josh_Bear
Thank you! That sets my mind at ease. I will use the towel method to proceed.

There's no need to have the components balanced independently then as a rotating assembly-- they are all component balanced in the first place.

I said it that way because, as a turbo rookie, I am mostly trying to take every word of wisdom from others to heart. The Brian Smothers turbo shop manual I bought describes separately balancing components and the assy, so that is how I will approach it with the local turbo shop that will do that bit for me. They may tell me otherwise. I'm learning from everyone.
 
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