k04 CHRA pictoral disassembly

[zenit]

Compressor wheel comes off with housing- *** REVERSE THREADED NUT***

[sheston]

Are you going to show us how to make it look like new again?

[zenit]

Originally Posted by sheston Are you going to show us how to make it look like new again?

pending parts or an exploding turbo, yes.

[zenit]

Rebuilding K03's - AudiForums.com

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.