Turbocharger Replacement

Introduction

Replacing the turbocharger on a 951 is not extremely difficult, but it is tedious because many components must be removed to access it.

If installing a turbocharger other than the factory K26-6 or K26-8 replacement, note the following:

• If the new turbocharger has a larger-diameter compressor inlet (e.g., K27), the stock rubber inlet plenum boot will need to be modified, and an adapter may be needed.
• If the new turbocharger has a larger compressor housing (e.g., K27), the cooling water outlet line (hard pipe) will need to be bent/reshaped to clear the larger housing. This may also cause the temperature sensor to contact the bottom of the intake manifold, requiring a low-profile detector.
• Ensure the turbocharger is a good match for your current setup. A different turbocharger may require remapped chips for the DME and KLR to achieve full benefit.

Questions to ask a turbocharger supplier before purchasing:

1. How do I know if this turbocharger is a good match for my current setup?
2. Are there any modifications or fabrication required to install the turbocharger?
3. Do I need a new set of chips to use this turbocharger or to get the best performance from it? If so, where can I get them?
4. Is there any additional equipment needed to get the best performance out of the turbocharger?

Other Procedures Needed

• AF-01: Air Filter Housing and Air Flow Sensor — Removal and Installation
• BOLT-01: Allen Head and Cheesehead Bolt Removal
• FUEL-02: Fuel Injector and Fuel Rail Removal and Installation
• FUEL-09: Intake Manifold Removal and Installation
• COOL-02: Coolant System Draining, Filling, and Venting

Parts Needed

Part Number	Description
944 111 205 03	Turbocharger Outlet Flange Seal Ring
944 111 205 04	Turbocharger Inlet Flange Seal Ring
944 111 205 03	Turbocharger Outlet Pipe to Cat Pipe Flange Seal Ring
999 707 043 00	Turbocharger Supply Line O-Ring (top of turbocharger)
900 174 058 40	Turbocharger Oil Discharge O-Ring (between bottom of turbo and motor mount bracket)
999 707 043 00	Turbocharger Oil Inlet Flange O-Ring (top of turbocharger bearing housing)
N 013 814 8	Turbocharger Oil Supply Line Banjo Bolt Seal Rings (2 needed)

Tools

• Jack stands or ramps
• 10 mm open-end wrench
• 10 mm socket, ratchet, and 6" extension
• 12 mm socket
• 13 mm socket and ratchet
• 15 mm combination wrench
• 15 mm socket
• 17 mm socket and ratchet, or 17 mm wrench
• 19 mm open-end wrench
• Thin-head 24 mm or 15/16" open-end wrench
• 5 mm Allen head socket or hex key
• Long 6 mm Allen head socket / long 6 mm hex key
• Medium flat-tip screwdriver
• Flat-tip jeweler's screwdriver or straight probe
• Phillips head screwdriver
• Catch rags
• Drain pans

Removal

1. Disconnect the battery negative lead.
2. Place the car on jack stands or ramps.
3. Using AF-01, remove the air filter housing and air flow sensor.
4. Loosen the clamps on either end of the intercooler outlet pipe (going to the throttle body). Disconnect the two hoses on either side of the intercooler discharge pipe and remove the pipe from the car.
5. Remove the rubber inlet plenum boot from the turbocharger inlet.
6. Using FUEL-02, remove the fuel rail and injectors.
7. Using FUEL-09, remove the intake manifold.
8. Remove the belly pan.
9. Using COOL-02, drain the coolant system.
10. Remove the alternator air supply flexible hose.
11. Remove the turbocharger cooling pump as follows: a. Disconnect the turbocharger cooling pump electrical connector (located along the shock tower near the cooling pump). b. Loosen the 10 mm nut at the strut tower holding the upper cooling pump bracket and the A/C line hold-down strap. c. On the back side of the master cylinder heat shield, loosen the bolt holding the bottom of the cooling pump bracket. Remove the bolt carefully to avoid dropping it. Slide the bracket off the top stud. d. Disconnect the coolant hoses from the cooling pump and remove it from the car.
12. (Optional) Remove the master cylinder heat shield. The turbo can be removed without it, but the job is significantly simpler with it removed.
13. Loosen the heat shield between the turbocharger and the engine block to gain access to the oil supply line banjo bolt (19 mm). Be careful not to drop the banjo bolt seal rings when removing the banjo bolt.
14. Remove the two bolts (15 mm) attaching the other end of the oil supply line.
15. Disconnect the supply and return cooling lines from the turbocharger.
16. Disconnect the flange for the turbocharger supply from the exhaust system.
17. Under the car, remove the heat shield for the steering shaft universal joint.
18. Loosen the four bolts mounting the steering rack to the front cross-member to allow the power steering rack to drop slightly, providing access to the lower turbocharger mounting bolt.
19. Remove the bolts from the triangle flange on the turbocharger outlet pipe (above the O₂ sensor). Also remove the M8 bolt attaching the flange to the engine block.
20. On the underside of the motor mount bracket, find the two Allen head bolts holding the turbocharger to the motor mount bracket. Using a stubby 6 mm socket, short 6 mm hex key, or 6 mm ball head hex socket, remove the two Allen head bolts.

Warning: It is critical to "wake up" the Allen head bolts (BOLT-01) before attempting removal. Failure to do so risks stripping the bolt heads. It may also be necessary to disconnect the motor mount bolt and jack the engine up on that side to gain sufficient clearance for proper hex tool engagement.

21. Lift the turbocharger out of the car. A short length of outlet pipe will remain attached to the turbo when it is removed.

Installation

1. Install the turbocharger exhaust-side outlet pipe on the turbo. Replace the flange seal ring.
2. Place a new O-ring in the groove on top of the motor mount (turbo oil outlet seal).
3. Install a new seal ring in the groove on the turbocharger hot-side inlet flange. A small amount of bearing grease will hold the ring in place during installation.
4. Carefully set the turbocharger in place on top of the motor mount. Avoid moving the turbo excessively once placed — movement can displace the O-ring from its groove and cause it to be crushed or cut when tightening the mounting bolts.
5. Install the two turbocharger mounting bolts from the bottom of the motor mount bracket.
6. Install the heat shield for the steering universal joint.
7. Install and tighten the turbocharger inlet flange bolts.
8. Install the turbocharger oil supply line. Install a new O-ring at the turbocharger flange and new seal rings for the banjo bolt at the balance shaft housing.
9. Install the mounting bolts for the balance shaft housing heat shield.
10. Install and tighten the mounting bolt attaching the turbocharger down-pipe triangle flange to the block.
11. Install the cooling water supply line and turbocharger cooling pump.
12. Install the master cylinder heat shield.
13. Attach the turbocharger cooling pump to the master cylinder heat shield.
14. Install the turbocharger inlet plenum boot.
15. Install the turbo cooling water outlet line and connect the turbo coolant temperature sensor.
16. Install the down-pipe triangle flange bolts.
17. Using FUEL-09, install the intake manifold.
18. Using FUEL-02, install the fuel injectors and fuel rail.
19. Using AF-01, install the air flow sensor and air filter housing.
20. Fill and vent the cooling system using COOL-02.