Can I rebuild a turbo?
 

That is the question.
I am fairly good with pulling things apart and then putting them back together. What I would like to know is how difficult would it be to put a rebuild kit through a KKK K27 turbo.
The reason for this is that from what I can understand is a seal has let go resulting in oil being dumped into the engine, there is no noise from the turbo to indicate anything terrible has let go and no noise from the engine, just clouds of burning oil.
Is this possible or do I need to be a rocket scientist?

It is possible, I have done it several times. But there are few things to notice. First thing is that you need to mark the position of the compressor wheel relative to the shaft (make a small scratch or something, not with pen, it will be washed out!).
And it will be visible when removing the compressor housing whether there is even point going any further: if the comp wheel has touched the housing, no point going further.

If wheel seems fine, remove the wheel and then you can access the backplate bolts etc. I don't have repair guide for KKK (I have done several Holsets and Schwitzers), but it would be useful so you can check the factory tolerances for rear seal groove wear limits etc.

Here are few links you might find useful:

Repair guide for KKK:
KKK Turbo rebuild instructions - anyone have them? - Rennlist Discussion Forums

Parts diagram:
http://www.vaglinks.com/docs/catalogues/melett.com_kkkcatalog.pdf

And here's some useful information also:

http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/857790-help-rebuilding-stock-k27-turbo.html

That's great so much information, I have just breezed over it all and will take some time to read it all carefully before taking any further steps. Initial concern is the comment on the quality of the rebuild kits from eBay.
Thanks heap Raceboy.

i did mine too but it did not work out. note: I more or less did it just because I wanted to try it.
the reason it did not work is because the bearing kit I got, no it was not an ebay kit, did not really fit properly. there was actually more shaft play with the new bearings and it puked oil.

the other thing is cleaning the body. mine had a lot of coking inside and cleaning it was a real pain.
I had durabuilt rebuild mine and even with a new shaft the price was not bad.

even though mine did not work I am still glad I did it.

I would advise against a home rebuild. Our turbos are very precise high speed with little or no room for error. "Scratching" the parts could lead to premature failure due to the loads imposed. Surely there are reputable shops around who specialize in turbo repair.

Turbo rebuild businesses love you!! :) There's is nothing wrong with rebuilding at home. A scratch will not destroy them. If that was the case, nicked wheels would explode easily. I've been around a lot of turbos with severely nicked blades that were fine. Big drag racers don't even use ait filters because nothing can handle the airflow without restriction and inject dirt like a vacuum cleaner.

As said, scribe a tiny index line and torque back to spec.

:D Old agricultural 3LDZ or K27 is high speed precision device?

I would barely call ball-bearing a precision device, but not a regular journal bearing turbo.

If you don't feel comfortable doing it, fine. But people do even crazier things, like surgeons for example who operate inside human body! without any tight tolerances, just huge knowledge base, common sense, and steady mind!

I suppose why doctors and lawyers practice their trades.

The turbine wheels spin at very high speeds, not sure but I'll bet over 50k rpm

How does a diy guy balance the rebuilt turbo?

You don't balance it at home. That's why presuming that your in-need- of -rebuild turbo is still balanced and just needs seals and thrust plates, etc., it's important to reinstall exactly in the same position on the shaft. A lot of folks here will say you're a fool to attempt, but then I've been called a fool before so WTF.

I rebuilt a K27 7200 I bought used "just because". Followed my own advice, and have yet to install and see if it hooks 'em up or goes ballistic.

Also, don't forget to Loctite the nut. If that puppy spins off at a quadzillion rpms, your turbo is FUBAR.

If the failure is due to blown seals then repair is within the normal realm of DIY.
If the failure is due to bearing damage or turbine wheel damage it may be best to let the experts handle it.
Worst case failure mode is the impeller explodes at 80,000rpm and sends shrapnel into your intercooler, muffler, and oil system. Not common but it can happen.

+1.

That's why I wrote in my post that if impeller has not touched the housing etc, proceed. Otherwise no point.

My old 60-1 had wheel contact on both sides, chipped vanes, and many, many nicks. This was due to a high flow K&N style filter mated right to the inlet ingesting all the road debris and tire kick up. It never flew apart. I pushed it to 1.2 bar for years. It was clearly spinning near max RPM as it was winded at high RPM's.

I'd imagine a triple-K can take more abuse than my old Turbonetics?

I've seen turbine wheels that look like they have been sandblasted. Those are not necessarily the dangerous ones, it's when the bearings go out and shaft play becomes so bad that the wheel can touch the housing by bouncing around that can cause catastrophic failure.

and if you lost your mark or changing out your compressor wheel...
» Turbo Balancing

its not a big deal if you do.
just mount the turbo on the exhaust and then line the body up to fit the oil line and then line up the turbo inlet side to line up to the IC,.

I lost the mark on mine and that is what I did. its no big deal and in fact it may fit better.

inspect the inside of the body, that needs to be VERY clean.

I have noticed that my bumper and rear fender are cooler after the rebuild. I think due to the fact that the caked on oil has been removed from the body allowing it to cool better.

can someone post who rebuilds the early 3ldz ones still

I rebuilt my original K26 but it was a long time ago when you could get a quality kit. Half the problem these days on not only turbos but also engines is junk replacement parts that don't meet OEM specs. I've had good luck with Midwestturboconnection for quality kits. I've rebuilt several Holsets with their kits and haven't had a problem. Re. balancing, as others have said, I mark the compressor hub and shaft and then reassemble the rotating assembly with the marks but then have the rotating assembly balanced at a turbo shop just to make sure before I put it into the housing.

Durabilt does them. I don't have any personal experience with them, but many here do - have been in business a long time and have a great reputation.

Durabilt Turbo - Turbo Rebuilding | Bradley, IL

That certainly is the best approach, but you're missing the point of this thread. This is DIY and for people that live in the middle of butt-crack-nowhere with absolutely no access to some outfit that can balance your assembly, well.....? We just take our chances. We tell ourselves"shoot, I can slap new parts into that bad dog, no problemo!". Anyone can do that, but keeping the turbo and compressor wheels exacta-freaking-mente where there were originally is the only way we can only hope the balance is still intact. Ya light her up, ya hope for the best, and she may or may not go balistic and throw metal filings all over the place.

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