Compressor wheel comes off with housing- *** REVERSE THREADED NUT***
K04 CHRA Pictorial Disassembly
- Thread starter ConeKiller
- Start date
Rebuilding K03's - AudiForums.com
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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.
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*****************
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.
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