Anyone rebuild there k03's for there S4 instead of buying new ones or upgrading to k04's? I might be buying a high mileage s4 and am wondering what im looking at to do this.

 

about 50 bucks per turbo if you do it yourself...kits on ebay

 

Any writeups on this anywhere? Im not about to pull turbo's from an S4 without a writeup, if I remember correctly the motor needs to be pulled to do it right.

 

writes up everywhere...use search button.

 

Once you get them pulled, here are the rebuild instructions.
Don't even attempt this if you are in question of ANYTHING!
Turbos are very precise and one tiny f-up will waste you a lot of time.


KKK K03/K04/K06 Rebuild Instructions:

The first step in rebuilding your turbo is to mark the compressor and
exhaust housings where they meet the bearing housing (center section), you
can do this with a scribe , punch, paint, etc.. (this will allow you to
align them exactly upon reassembly and making installation of the turbo
easier). It is best to pick a point on the bearing housing and mark
everything with that point. Example: I mark everything to the oil drain
of the bearing housing, so when we mark the exhaust housing, I punch a
mark on the exhaust housing that lines up exactly with the oil drain. I
do the same thing with the compressor housing. This allows you to always
have a reference to go back to even if something happens to your marks
(ex:
if you use paint and it was washed away when you used carburetor cleaner
to clean the compressor housing). After marking the housings, use a 10mm
wrench to remove the rear nut holding the wastegate actuator arm to the
wastegate lever on the turbine housing. Now, remove the two 10mm bolts
that attach the wastegate actuator to the compressor housing, and then
remove the actuator. To remove the turbine housing, you will need to
remove the six 10mm bolts that attach it to the bearing housing. Once
these bolts have been removed you can now tap the turbine/exhaust housing
off with a hammer, working in a clockwise rotation all the way around the
housing. If the housing is really stuck you will need to do this several
times before it breaks loose. Once the turbine/exhaust housing is removed,
remove the two remaining 10mm bolts that attach the compressor housing to
the bearing housing. The compressor housing is attached to the sealplate
assembly with anerobic sealer (Loctite 5127), the only way to seperate these two parts(the compressor housing and sealplate) is to place the turbine wheel end
nut into a vise and firmly clamp it down. Once the assembly is clamped
down tightly (you do not want the turbo to come out of the vise now or
severe damage will occur to the fins of the wheels), you will need to use
a small propane torch (like plumbers use to sweat in pipes), a set of
leather gloves and a preferably a two jaw puller. You will now need to
heat the base of the compressor housing while rotating the assembly in a
clockwise rotation. As the housing heats up the sealer will slowly start
to let loose, now install the two jaw puller on to the compressor housing
and slowly start to pull the housing off of the seal plate. This may take
a few minutes to get the housing to come loose, just keep working with it
and heating it and it will come. When prying up on the housing, be careful
not the apply to much pressure in any one direction as this could damage
(bend) the turbine shaft assembly and if the compressor housing comes off
quickly then damage could also occur to the compressor wheel.

The next step is removing the compressor wheel and turbine shaft. First,
you will need to mark the compressor wheels relationship to the turbine
shaft. You can do this by scribing a mark on the compressor wheel, the
seal plate and then painting the fin on the turbine wheel that aligns with
these marks. Failure to do this could result in turbo imbalance, and would
require the assembly to be rebalanced. Next, remove the compressor wheel
by using a 8mm or 10mm end wrench depending on your application. The
threads of the shaft can be standard or reverse thread so you must look at
the threads and trace them to determine the direction in which the nut
needs to be turned to be removed. Failure to turn the nut in the correct
direction will break the turbine shaft. Once the compressor wheel lock nut
is removed, the compressor wheel will need to be slightly heated with a
propane torch, as the wheel is heated it will expand and allow you to
remove it and the seal plate. When removing the wheel/seal plate leather
gloves must be worn or your hands will be burned. Once the compressor
wheel is removed, remove the assembly from the vise and gently tap the
turbine shaft out of the center/bearing housing with a rubber mallet.

Once the compressor wheel, seal plate and the turbine shaft have been
removed, the next step is to remove the oil deflector and thrust bearing.
The oil deflector and thrust bearing can be removed with a pick or small
flat bladed screw driver. After the oil deflector and thrust bearing has
been removed the thrust washer can now be removed, with a pick, or magnet.
The retaining ring for the journal bearing will now need to be removed
with a flat bladed screw driver. Now remove the locking plate and remove
the journal bearing from the bearing/center housing. The turbo is now
completely dissassembled.

*Special Note*: Inspect all bearing surfaces, making sure there are no
grooves, pits, or ridges. Also, thoroughly check all sealing surfaces and
piston ring grooves, making sure they are smooth and not oversized.
Reverse this entire procedure for reassembly, paying special attention to
line up the marks that were made prior to the disassembly.

*One more note:* Bearing housing choking is a very common problem with all turbos. It is caused by the turbo not being properly cooled off when the engine is shut off, and/or irregular oil changes. To check for this
problem, look for black carbon deposits throughout the inside of the
bearing housing, especially on the rear side where the turbine shaft goes
in. The bearing housing should have an open area that you can see light
through from the oil drain back to the rear sealing area where the shaft
goes in. If you cannot see through the bearing housing, from these two
areas, then you have severe coking and all of this carbon must be
removed, or the turbo will fail almost instantly on startup.

Now, completely and thoroughly clean the whole turbo with solvent. It
needs to be very clean, this is very, very important. Reverse the
procedure above and reassemble the turbo using high quality engine
assembly lube on all bearings and sealing surfaces.

Compressor wheel installation/torquing: First, wearing a pair of leather
gloves slightly heat the compressor wheel and then place it on the shaft
it should slide completely to the bottom. Next, align your marks and
install the compressor lock nut. For left hand or reverse threads, lightly
oil the threads and then hand tighten the compressor wheel lock nut until
it touches the thrust collar torque to 28 in/lbs, then turn an additional
1/8 of a turn. For right hand or standard threads, place two drops of
medium strength thread locker on the threads and then hand tighten the
compressor wheel lock nut until it touches the thrust collar torque to 28
in/lbs, then turn an additional 1/4 of a turn.

 

Im a buy a rebuild kit for the turbos. If you want to wait I'l take pictures to show you. PM me if you want me to.

 

I have rebuilt a number of turbo's over the past 10 years. Red 01 covered just about all necessary steps.
There is no such thing as being to picky when rebuilding these. Take your time, mark, identify, and grease. In my experiences, Oxygen and sedaline is a must have. You can remove the centers with butane but it's slow and not as effective. Butane just isnt hot enough and allows castings to reach equal temps over prolonged heating. If you dont have a cutting torche i reccomend you borrow one.
If you have further questions feel free to email me pepsicolla4444@yahoo.com or check my post history. I have responded to many treads regarding rebuilds, and you should be able to find some useful info on there.
If you cant retain stock balancing than hit me up. I know of a real good shop that balances each center for $60 pc.

 

I recently bought this Audi and the guy said the turbo is bad. it smoked really bad and leaked oil out of the exhaust. i look on some forums and what i read was that indeed i do have a bad turbo/turbos. i got the motor out no problem. i then took off the turbos and the turbo on the drivers side the turbine was just sitting there. the shaft is broke and i do not know where to get one or the right one for my car. if you guys can advise me in the right direction it will be gratefully appreciated and i do have the rebuild kits on there way for both turbos. ps new to the site and a lot of info on here but i couldn't find anything about the turbine shaft wheel.