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Discussion Starter · #1 ·
So my local tuner told me I had rods let go from cyl 2 and cyl 4! They said at first sight the turbo looked good while removing my engine. They said they can't see the inlet tho yet. Today I called and they said my turbo was garbage that there were metal shavings in it and it cost as much to rebuild as a new one. I have been reading other posts in this and I found this ......

"I saw a lubrication diagram for the EJ series engines awhile back. If memory serves me correct, the heads/turbo are on the same oil circuit and the bottom end is a separate circuit.

Any garbage that the bearings spit up will get dropped back into the sump and screened by the pickup/filter.

Even if a small amount of particulates got into the turbo itself... anything small enough to not cause immediate turbo bearing failure is no worse than metal shavings that get introduced during normal engine break in.

I think the mechanic
a) has no idea what he's talking about
b) is trying to make some more $ off ya
c) all of the above

All the spun bearings I have seen are due to the motor being doomed since day one (improper assembly, poor clearances, etc.) or due to oil starvation or excessive RPM.

Particulates in an engine spin bearings when they get BEHIND the bearing (during assembly) and mess up oiling clearances.

The easiest way to see if it is noise in the short block or valve train is to beg/borrow/steal a timing light.

Move the light around to each plug wire until you get a flash as close to the noise as possible. If you get one flash per noise, it's most likely something in the valvetrain. If you get two noises per flash it is in the short block.

If the noise turns out to be something in the valvetrain you most definately have particulates in the turbo bearings. See my above statement about particulates in the turbo bearings.


So could shavings get in my turbo or is it screened and they are just taking me for a ride ?


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9/10 times spun bearings are lack of maintenance and abuse. I can't speak to the turbo, but it wouldn't be out of the realm of imagination to say the same oil failure that killed the bearings killed the turbo.

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Discussion Starter · #3 ·
I'm asking more about the anatomy of
The engine and if shavings are caught before the turbo by any filter


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The turbo has a bearing in it that if dry will make shavings. What happens elsewhere is beside the fact.

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Discussion Starter · #5 ·
Ok, so your not answering my question of if my rods letting go creating metal will or will not in fact spread metal to my turbo. My turbo didn't die from a spun bearing.


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It is completely beside the point. Your filter should catch everything unless it clogs then the bypass spring opens and allows all kinds of stuff through. The mesh won't catch the small sand like particles common with failing bearings or metal wear. Those particles can get past the filter and to the turbo causing failure of its bearing and metal shavings there.

Yes it's possible your turbo could have died from spun bearings, it's more likely your turbo died from the same thing that caused the bearings to fail. If you don't trust the shops answer tow it to a different shop.

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1) Two rod failures points toward oiling problems. Not for sure, since one bearing being damaged (not necessarily "spun") could have put enough babbitt into the oil that the second bearing suffered, but I would still bet on a failed oil pump, failed/stuck open oil pump bypass valve, or just plain low oil level.

2) Re the turbo, an ounce of data trumps a pound of theory. Why don't you take a look at the thing and see if it spins OK or not? That will tell you a lot. And, yes, a bunch of babbitt in the oil could have messed up the turbo bearing oil flow as well.

3) Cut open the oil filter and see what you have. That will be educational, at least, if not useful in further diagnosis. If there is metal, a magnet will tell you whether it is babbitt or not.
 

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Discussion Starter · #9 ·
1) Two rod failures points toward oiling problems. Not for sure, since one bearing being damaged (not necessarily "spun") could have put enough babbitt into the oil that the second bearing suffered, but I would still bet on a failed oil pump, failed/stuck open oil pump bypass valve, or just plain low oil level.

2) Re the turbo, an ounce of data trumps a pound of theory. Why don't you take a look at the thing and see if it spins OK or not? That will tell you a lot. And, yes, a bunch of babbitt in the oil could have messed up the turbo bearing oil flow as well.

3) Cut open the oil filter and see what you have. That will be educational, at least, if not useful in further diagnosis. If there is metal, a magnet will tell you whether it is babbitt or not.
I was running with knock for hundreds of miles before it let go,(oil level was topped off) I was suprised to hear that BOTH driver side rods broke... after reading that there's a filter before the turbo it makes me suspicious that shop is upselling me. First inspection of the turbo was fine on the exhaust side.


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Discussion Starter · #12 ·
The turbo has a bearing in it that if dry will make shavings. What happens elsewhere is beside the fact.

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What do you think about $5100 in parts alone for a OEM STi shortblock ?


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I am pretty sure the ROD BEARINGS let go, and not the rods. Yet you keep saying rods...
 

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I was running with knock for hundreds of miles
Oooo .... Bad idea. But you know that now.

What that knock was doing was pounding babbitt material out of the big-end bearing and putting it into the oil. As someone previously mentioned that may have been enough to clog the filter and cause the filter bypass valve to open. Game over at that point: Then (still guessing a bit) the oil galley to the second rod bearing may have gotten clogged and the rest is history.

before it let go,(oil level was topped off) I was suprised to hear that BOTH driver side rods broke ...
Now that you explain, I'm not surprised at all.

Good on you that the turbo is OK. Be very careful, though. Whatever oil passages there are in the turbo itself will have to be very carefully cleaned with brushes, flushed with parts washing fluid, and inspected by a raving paranoid. This may well entail tearing the thing down.
 

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Discussion Starter · #15 ·
Oooo .... Bad idea. But you know that now.

What that knock was doing was pounding babbitt material out of the big-end bearing and putting it into the oil. As someone previously mentioned that may have been enough to clog the filter and cause the filter bypass valve to open. Game over at that point: Then (still guessing a bit) the oil galley to the second rod bearing may have gotten clogged and the rest is history.

Now that you explain, I'm not surprised at all.

Good on you that the turbo is OK. Be very careful, though. Whatever oil passages there are in the turbo itself will have to be very carefully cleaned with brushes, flushed with parts washing fluid, and inspected by a raving paranoid. This may well entail tearing the thing down.
My tuner didn't mention this, thanks!


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Hundreds of miles with fried bearings? Man, yeah it's completely possible in that length of time the particulate are up the turbo.

Usually with a dead bearing they last hundreds of seconds.

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Discussion Starter · #17 ·
Hundreds of miles with fried bearings? Man, yeah it's completely possible in that length of time the particulate are up the turbo.

Usually with a dead bearing they last hundreds of seconds.

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Yes my local mechanic said that he has driven cars with knock for a year or so, granted he said that was about 10k a year.
I thought I would give it a shot until I could afford the repairs


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Find a new mechanic. If this is the same guy working on the car now find a performance shop with a good reputation with Subaru and pay to have the car towed there. Don't ever drive a car with rod knock. What may be just a short block may wind up an entire long block plus.

Sadly at this point I would begin to start saving because there is a likely hood you may have damaged a head.

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Discussion Starter · #19 ·
I already brought it to my local dyno tuner. I'm not sure they are much better now


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Updated the last post, my phone went haywire.

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