Bent Exhaust fins? Subtle?

[DSMDEMON93]

So I finally picked up a LEGIT mhi evoIII turbo. I am so stoked, upon checking it out, I noticed that one or two of the exhaust blades might be bent? How much of an issue would this cause me? I am aware if the damage is too severe a rebuild is in place, and balance so the whole thing doesn't grenade, but some input would be appreciated!

FIRST PHOTO: BENT FIN?



SECOND PHOTO: NORMAL

 

[Heartless]

Any shaft play? My friends e316g has bent and messed up intake fins and it pulls just fine, im sure on the intake side it may disrupt airflow some and perhaps on the exhaust side may change spool but I personally can't say as it would seem to be an issue, it just would not operate to its full potential or if it was that far out of balance it would destroy itself in a short time..... Did it come off of a running car? If you don't have much in it, it can't be too terrible cost wise to replace it.

 

[DSMDEMON93]

No shaftplay at all. It has come off a running car as well. I suppose I could replace it. All I wanted to do was strap it on and go fast! .

I was under the impression the exhaust wheel and the shaft are one unit? Or am I misinformed?

 

[silvreclips]

Yes the exhaust wheel and shaft are one unit. You can get a brand new turbine for about $65. I would plan on replacing it, there is no way to tell how long it will last running like that but it may experience pre mature bearing wear and could possible damage other parts as well.

 

[johnmel]

Um I and don't recommended this but I have had a slight broken fin and two are bent on mine and there's no shaft play at all it runs fine pulls great and I've been like this for three months now. But again I'm not saying do it

 

[JusMX141]

It needs rebuilt anyway- that thing's losing a TON of oil on the turbine side. Heat shield is soaked, turbine wheel has oil coking all over the back of it.

 

[atownturbo]

It needs rebuilt anyway- that thing's losing a TON of oil on the turbine side. Heat shield is soaked, turbine wheel has oil coking all over the back of it.

Beat me too it

 

[DSMDEMON93]

Sounds like a plan. My plan was.
-take completely apart and beadblast everything
-buy new shaft
-install new rebuild kit
-rebalance (since its a new shaft)

 

[talontd92tsi]

I'm no expert, but I wouldn't be too sure that beadblasting a CHRA would be a great idea. If it were me, I'd sent it to Justin, and be confident that I was getting a properly built turbo. If memory serves me correctly, MHI turbos are component balanced, meaning that each component is already balanced, so therefore a rebalance would be kind of useless.

Someone correct me if I am wrong.

 

[Purple_Demon]

Correct^

 

[JusMX141]

Don't media-blast the center housing unless absolutely necessary to remove any internal oil coking.

Honestly the bend on that blade isn't all that bad- I'd be tempted to run it if it didn't have oil puking out the turbine seal.

If memory serves me correctly, MHI turbos are component balanced, meaning that each component is already balanced, so therefore a rebalance would be kind of useless.

Each part is indeed balanced individually, but MHI will then balance the assembled turbo on a VSR. This is done to most Evo III 16G's I've seen. If you want it to be right, you'd get the rotating assembly rebalanced or at the very least mark the alignment of the compressor locknut to the compressor wheel and make sure they align with the new turbine installed.

 

[DSMDEMON93]

Don't media-blast the center housing unless absolutely necessary to remove any internal oil coking.

I see. That makes sense, before I knew anything about turbos, a rebuild shop in Socal..Turbochargers.com I believe mediaplasted one of my turbos, or "strongly advised", but I guess anything to squeeze 20bucks out of you. Since then, I've done a few journal bearing rebuilds in my garage, but I usually use Chem-dip, a carb cleaner to soak the CHRA.






My rebuild kit should be here Wednesday, so I think with my paycheck I just received today...to bite the bullet and get a new turbine shaft.

Or not and kick my own ass if the rebuild fails.

 

[JusMX141]

There are a handful of turbos that need to be media-blasted to remove coking inside the cartridge where you cannot see or reach with tools. A 14B with 200K daily-driven, hot-shutdown miles that has been on three different cars absolutely needs this to be done to verify that all of the oil passages are clear and the journals can get the full amount of oil they need. A 16G that has likely been turbo-timed or previously installed on a car where the owner is more inclined to use better oil or service the car more frequently will probably be just fine.

Should you choose to media-blast the center housing, it needs to be stripped- the snap rings for the journal bearings must be removed, the roll pin to keep the thrust plate from rotating must be pulled- otherwise you run the risk of media getting trapped inside the cartridge.

After it's been blasted, the housing should be washed 2-3 times in warm water with a strong dishwashing detergent, then blown dry using compressed air to verify that all of the media is out. Once dry you should then install new snap rings in the journals and a new roll pin in the thrust plate location...then proceed with reassembly.

I've done a few journal bearing rebuilds in my garage, but I usually use Chem-dip, a carb cleaner to soak the CHRA.

The Chem-dip will remove the existing oil residue, but it's designed for gunky old carburetors....not turbocharger cartridges that have had oil baked to them at 1500*f. The only way you'll get rid of heavy oil coking (should it exist) is media blasting.

 

[DSMDEMON93]

There are a handful of turbos that need to be media-blasted to remove coking inside the cartridge where you cannot see or reach with tools. A 14B with 200K daily-driven, hot-shutdown miles that has been on three different cars absolutely needs this to be done to verify that all of the oil passages are clear and the journals can get the full amount of oil they need. A 16G that has likely been turbo-timed or previously installed on a car where the owner is more inclined to use better oil or service the car more frequently will probably be just fine.

Should you choose to media-blast the center housing, it needs to be stripped- the snap rings for the journal bearings must be removed, the roll pin to keep the thrust plate from rotating must be pulled- otherwise you run the risk of media getting trapped inside the cartridge.

After it's been blasted, the housing should be washed 2-3 times in warm water with a strong dishwashing detergent, then blown dry using compressed air to verify that all of the media is out. Once dry you should then install new snap rings in the journals and a new roll pin in the thrust plate location...then proceed with reassembly.




The Chem-dip will remove the existing oil residue, but it's designed for gunky old carburetors....not turbocharger cartridges that have had oil baked to them at 1500*f. The only way you'll get rid of heavy oil coking (should it exist) is media blasting.

Ahh I see. Good good, thank you for the words and wisdom good sir!