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Bending fins?

1482 Views 25 Replies 6 Participants Last post by  Stealth
So i just took a look at my compressor side and noticed that the fins are currently disfigured.

I have a t3/t40e 60 trim, and the fins on the compressor are bent and scratched like. the shaft play is minimum, but more than it was prior to install. There is no in and out shaft play

it smokes, while accelerating and decelerating, i have pictures but cannot find the cable for transferring, i will get them up asap

also my bov doesn't seem to be working, and i think i am experiencing compressor surge, could this be the cause of that? I have a thin layer of oil in the compressor housing, and that was probably due to running unrestricted for a while...

could anyone give me some insight on what happened or what i should do?

Also how bad is it to run a turbo that has some really fucked up fins

ALSO, i have an idea that might work

if i got an exhaust housing for cheap or free, and took out the center cartilage and turbine, and then blocked off that hole with some sort of metal and bolted it up, and just recirculated my feed and drain lines together, would that work? The exhaust would flow as it did before, it just wont spin anything.

it sounds ridiculous, but i need to drive,
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From your other thread as well, sounds like your turbo is a sure fire dud mate. Time to replace.

Regarding the empty turbo, it would work fine, probably not worth the effort though. Also you are better off just blocking the feed/drain to how it was before. You can get a -an plug to block off the oil drain They arent that hard to change anyhow. I wouldnt bother though. Just get a decent ebay turbo for $200. Ive had mine for 1 year, it out lasted the engine :).
well the turbo block off thing would be easier than blocking off the oil feed and drain if i can find a connecting fitting from a -3an to a -10 an haha , but my intercooler pipes that run infront of my valve cover is just really hard to put on, and the feed line runs underneith it and is just really hard to get off and on since its in an awkward position

i chose this idea because i doint have to touch anything besides the area where the turbo is, and i have plenty of room to do stuff

Has anyone heard of the single spring mod for the greddy type s bov's?

i've tried to use the single small spring, set at the lowest level, it wont work as the car will just die, and the pull piece will just go in maybe a mm before stopping due to the screw plate.. has anyone had to deal with this before? I havn't tried the big spring yet to see if that will fix my problem, but at the moment i have my bov permanently shut although it was permanently shut before for some stupid reason and never opened and probably was the cause of my problems now, but i rather screw up a screwed up turbo that a turbo that is already rebuilt lol '

this is what im talking about

EVO Motorsports - Evo VIII Performance Upgrades and Accessories -

taken from an evo 8 website link
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I had 2 type RS valves and they each had 2 springs inside of them. I dont know why you would want to change it.

You need to get your BOV functioning before you put a new turbo in or the compressor surge will bend the fins on your next turbo as well.

Might as well run this one until the fins break off and make a bang. What brand of turbo? If its a cheapy just run it till it dies, if its a nice name brand turbo you probablly want to get it re-built before the big bang.
well i donno why my bov's doesnt open, and they are both greddy's it sucks
im trying to get it to open correctly with this turbo.. although its garret, i rather screw this up more and get a new blade rather than fix it twice testing out how to get my bov to work lol

i dont want to blow up this one i jsut want to get my bov to work lol then go rebuild my turbo
Just make sure you have the port on the BOV hooked to the manifold somewhere, and not on the intake piping. Its pretty much fool-proof.

Take the valve off and push it by hand to make sure its not seized up. After that, get a new valve and dont take it apart until you make sure it works :)
ive taken my bov off severeal times to make sure it isnt seized
ive swapped over between the 2 bov's i have too, and still no effect, i really think the spring is to tight for like 3 psi or so, i know they are all free flowing and moving

ive just actually took out the bigger spring and set the bov in on max setting or just before it, and i can hear it leak and idle drop, and then i tighten it and it will not leak and idle will be nice and dandy, but that only happens when the plunger will not be able to move from its spot to maintain an actual idle with the small spring.. but with the big and small spring i couldn't get it to work, so im going to just try the big spring, and see how that goes

im getting my vac/boost source from the big nipple that is right after the TB on the im, its that big one that used to go to cruise i think? its then reduced into a smaller vac line for me to attach it in a T for my boost gauge and bov
Yes that port on the manifold will work for a bov. I didnt know you were only running 3 psi, I doubt 3 PSI of compressor surge is enough b oost to bend a fin.

If you have compresor surge you will know it, it sounds like a hollow fluttering (many times sounds like the BOV) but dont let it trick you its the wastegate.

How many PSI spring in the wastegate?
5 or 6 psi wastegate, i have barely every full throttled a full gear yet, i have never even heard my wastegate dump but i watch my boost gauge and wideband all the time when i even touch the gas, and it rarely goes to even 2 psi lol

i guess 3 psi will screw up some turbo fins pretty damn bad, when u see the pictures ull see what happened

or it could be the spilling oil? lol who knows
I would say its more likely the oil made it off balanced than 3 psi compressor surge.

Lets see those pics.
here are some pics, although they are blurry for some reason but u can obviously see what is going on

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Wow, yeah that is some bad damage. Is there any shaft play at all? up down / in out?
no shaft play in and out, and very minimum up and down or left and right.. like its more than when i first got it obviously, but its nothing like horrendous it doesn't feel blown
Well, the clearance of the fins to the housing is very small. If there is any shaft play it can easily bend the fins, and with the smoking problem you have been speaking of it would seem that between the shaft play and oil causing it to be unbalance it might have rubbed the housing and bent the fins.

Is there any damage on the housing?
i havnt taken the turbo off to look inside it

its very weird, im pretty sure my seals are gone and this turbo is screwed but, it doesnt show it besides these really bent fins, which is a big thing but its just weird
thats alot of damage for shaft play... Id point the finger at =no filter over the turbo. Something got in there and screwed up those blades.
Also for surge to do real damage, your looking in the 10+psi.
Shaft movement usually allows the compressor wheel to grind itself around in the compressor housing.. normall the tips of the fins are wore down, not chipped off like it was sucking up rocks.
That or just shitty turbo, who knows maybe they are making compressor wheels out of potmetal and gluein them together

At this point id be worried where the material from the compressor wheel went..
well i had the vaf in front of the turbo

it might of sucked something up, but who knows
Vaf and a filter, or just a vaf?

Even an installation error could cause this... "like a screw you dropped and couldnt find.."

From the pics, it looks like your compressor wheel is destroyed.
I second king6's belief, something foreign hit that compressor wheel. Thats the only way to get that much damage for 3psi, no shaft play and a small oil drip.
just a vaf alone, in the pics the compressor wheel has 2 sets of fins.. and it seems like the outter set is destroyed and the inner one is fine

it is possible that something fell in there

i heard when driving what sounded like to be a flag pole tinging sound, which intern i thought was detonation.. but now i realized that it could of been something that fell into my turbo.. sorta makes sense, but its a lot of speculation

i guess i should go get a real vaf setup after the bov and put a filter on the end of my new turbo to make sure that doesn't happen again

but then i have to figure out why my bov doesn't work
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