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Old 05-28-2009, 02:43 AM   #1
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Default what happened to my poor bearing??

This is interesting, I rebuilt my turbo about 10k miles ago, and when I went to re do the exhaust today, I found the turbo had mega shaft play! I was lucky I checked it. It was seriously very close to killing itself. interesting thing is its just the turbine side bearing, the compressor side bearing looks fine (its in the pic).

Question is is this because of over heating or lack of oil for only that one bearing? Any ideas? Can I check the oil passageways?

Also, is the shaft still usable? Its discolored, but not bent from what I can tell.

Finally, when I put it back together awhile back, and I dident pay enough attention to how everything lined up for balance. Could a mis balanced shaft cause only one bearing to fail?

Thanks

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Old 05-28-2009, 03:02 AM   #2
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[QUOTE=cardriverx;412601]

Finally, when I put it back together awhile back, and I dident pay enough attention to how everything lined up for balance. Could a mis balanced shaft cause only one bearing to fail?

QUOTE]

Im not 100% sure but i think so. I know some people have ran forever without having the shaft rebalanced but others have had bearing failures.
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Old 05-28-2009, 03:08 AM   #3
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[QUOTE=sbkcocker499;412605]
Quote:
Originally Posted by cardriverx View Post

Finally, when I put it back together awhile back, and I dident pay enough attention to how everything lined up for balance. Could a mis balanced shaft cause only one bearing to fail?

QUOTE]

Im not 100% sure but i think so. I know some people have ran forever without having the shaft rebalanced but others have had bearing failures.
The thing is I would think that would cause both bearings to fail like that, I dunno.
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Old 05-28-2009, 03:42 AM   #4
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Depends on where the imbalance was. Get something spinning >100,000 rpm and even something so tiny can cause a lot of excess heat from all of the extra pressure. I would say that is possibly your issue. Can't think of any other reason only one side would overheat like that.

I would think the shaft may be OK, but its not like you would be able to tell yourself with your own tools (unless you rebuild turbo's).
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Old 05-28-2009, 09:32 AM   #5
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Did you check for a blockage in the feed and drain lines in the housing on the turbine side?

I'd buy a rebuild kit, and ship the rotating parts to Cherry Turbo for balance, he can also tell you if the shaft is ok or not.
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Old 05-28-2009, 09:52 AM   #6
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are the oil passages on the one bearing clogged? which one was it, the compressor side or turbine side?

Looks like coked oil blocked the oil passage. is your turbo water cooled?
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Old 05-28-2009, 12:07 PM   #7
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Quote:
Originally Posted by Braineack View Post
are the oil passages on the one bearing clogged? which one was it, the compressor side or turbine side?

Looks like coked oil blocked the oil passage. is your turbo water cooled?
Turbine side, not water cooled.

how can I check the passages inside the CHRA?
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Old 05-28-2009, 01:28 PM   #8
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Pour oil in the inlet w/ the rotating ***'y out, look if it's running out both sides at same rate.
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Old 05-28-2009, 02:07 PM   #9
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this is what your passages look like:


http://www.allpar.com/images/cars/fe...cuda/turbo.jpg


soaking it in a detergent or sea foam probably wouldn't hurt.
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Old 05-28-2009, 09:08 PM   #10
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kk, ill try to pour some oil through it.
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Old 05-30-2009, 07:37 PM   #11
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Well the turbine side bearing is getting oil, maybe alittle less than the other, but i dunno. Could i put the whole center section in a simple green bath just to make sure?
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Old 05-30-2009, 09:36 PM   #12
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Honestly, that shaft looks fine; get it cleaned up and balanced by Cherry. Last CHRA I rebuilt looked worse than that, think Jim charged me like $30 or something. The higher the imbalance, the higher the radial loads and the quicker the wear.

How does your turbine wheel look? Intact?
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Old 05-30-2009, 09:54 PM   #13
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Hotlinking fail.
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Old 05-30-2009, 10:54 PM   #14
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the wheels look fine, could I bathe everything in simple green to clean it off?
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Old 05-31-2009, 10:09 AM   #15
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Turbine shaft: hit with brake cleaner, probably won't clean it completely. I think they typically "sand" blast it (dunno what media they use, glass maybe)

Center housing and turbine heat shield: remove everything, soak in brake cleaner, dry and coat w/ oil (it'll rust)

Compressor wheel: Don't hit w/ brake cleaner

Bearings: Replace w/ new
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Old 05-31-2009, 10:09 AM   #16
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seems like the turbo's not getting enough oil, also the oil went through it is very contaminated. Note all those scrolls on the bearings.

For this to work. You need to horn out your bearing housing, Check shaft tollorance, and use over sized bearings.
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