if a turbo has oil blow by, how is that fixed?

i never called turbonetics... obviously theres production tolerances for all the components, but he could be right about shaft play on a used turbo. a lot of those things are hard to measure anyways - how are you going to measure in-out shaft play on a compressor? and as for side-to-side, yeah you can use feeler gauges to check the clearance to the side of the housing, but two identical measurements could mean totally different things. on one compressor it could be normal wear-and-tear on the bearings, on another it could indicate catastrophic failure of the turbine bearing.
to accurately get any measurement of the amount of wear in the bearings, or to check any meaningful tolerances youre gonna have to crack the whole thing open. thats what the shop said and i have to agree - and if youre going through that much trouble, why not just rebuild it?
the only tests i could see being useful is on a bench test for turbos - one where they get the thing up to operating speed to balance the shafts and such. im thinking that could accurately measure bearing resistance and that may have specifications.

...but i will email garrett to see if they can give me some specs. ive been wondering ever since i went to that shop.

I agree with the statement in Bold lettering. BUT, It's not an all or nothing scenario. You can make an educated assumption about a turbos general condition w/out tearing it apart...

I'm not saying that I'm definitely right, but it seems very obtuse of that Technician to say that shaft play indicates nothing of a turbos condition. That's a very generalized statement, that I personally don't buy...
 
I was able to measure in/out shaftplay with my calipers...depth from the comp housing face whille pushing in on the shaft and same while pulling on the shaft. You also have to realize when there is no oil flowing through the bearing there is more play. I had about .012" but it felt like alot more. This was with my IHI sleeve bearing turbo so quite different but still same...


^Yes there will be a puddle of oil on the inlet of the comp housing if seals are going bad and blue smoke in your exhaust.


Very important to keep that in mind. Additionally, I don't think you'll see much smoke unless the turbine side is bad.
 
As it stands right now, you're going to get conflicting advice on this. I'd go ahead and call either garrett, or a well known rebuild shop for information. Be wary of people misleading you though, as they may just want you to worry and send your snail in to be re-worked.

If you want to check the compressor side for oil leakage, you need to first eliminate the other variable that can put oil there, AKA remove your valve cover vent from your intake-to-turbo pipe. Clean any oil you might see right then in the compressor inlet and intake pipe, and reinstall the intake but NOT the valve cover vent hose. Go drive the car for a few days, with some hard pulls w/ boost. Check back on it and if you see oil pooling then it's likely you have oil pushing past the seals.
christ i thought you left. did you come back just to s*** on my parade? anyways, everything in this post is correct.

as for this whole debate, ive formed my own opinions on what shaft play indicates and what to be concerned over, and not all of them align with the guy who looked at my turbo. you will definitely get conflicting opinions on this, and its best to read through as many opinions as you can to understand whats going on, then form your own.
my opinion? its overrated. its a good - and often, important tool to help indicate the history of the turbo, and maybe the reliability of the person whos selling it. but it is not the end-all, be-all that people want it to be. the fact is, youre buying a used precision part that you cant see aside from pictures, and youre making an educated guess to the condition.
 
Easy killer(gtfo), haha . I came back to offer my experiences and input. I generally don't assume things, and when I speak, it's based on something real rather than hearsay. I still say his best bet is to contact Professionals about this. If I'm wrong, so goes life, I'm not here to be right, rather I'm here to try to help those who ask for it. Nothing I say is definitive or concrete, again, it's merely my experiences that I find applicable to the issue at hand.


Now, Bryan, where is that bowl of Cheerios ? (piss) ;)
 
im just bustin your balls. we need all the technical people we can get around here.

unfortunately, the OP doesnt have the turbo - hes looking at a few kits. and in his case, if the seller is saying theres "blowby" in the turbo, i would be hesitant to get that one. to fix the seals on the OEM turbo, you need a new rotating assembly, and at that point, you might as well buy a new one... the CHRA is 700-800 bucks.

as for the other guy whos having problems, you have to check a bunch of things to figure out where the oil is coming from. the turbo is a candidate, as is the PCV. do you have a boost gauge and wideband to make the diagnosis easier?
 
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