Volkswagen Front Wheel Drive 1974-1989 Repair Guide




See Figure 1

  1. Disconnect the negative battery cable. Drain the engine oil and remove the oil filter.

Whenever the turbocharger is replaced, especially in cases of a turbo failure, it is good practice to change the oil and filter. If the turbo failed, metal particles from the compressor shaft bearings will have contaminated the old engine oil. Not changing the oil and filter may allow these particles to wipe the compressor shaft bearings of the new turbocharger and destroy it. The amount of money spent on oil and a filter is relatively cheap insurance to ensure successful and sustained operation of the turbo.

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Fig. Fig. 1: A common turbocharger system used on Volkswagen turbo diesel engines

  1. If applicable, remove the engine and transaxle cover shield to gain access to the turbocharger.
  3. If equipped, loosen the stabilizer bar clamps on both sides of the stabilizer and push the bar down out of the way.
  5. Remove the turbocharger heat shield mounting nuts. Disconnect the oil return line adapter flange at the bottom of the turbo. On Quantum models, also remove the side bolt. Plug the end of the line to prevent leakage. Have a container ready to catch any oil.
  7. Remove the turbocharger-to-intake manifold and air cleaner hoses.
  9. Loosen and remove the oil supply line to the turbocharger.
  11. Remove the exhaust pipe-to-turbocharger mounting bolts.
  13. Remove the turbocharger exhaust manifold mounting bolts, then remove the turbocharger.

To install:
  1. Coat the threads of turbocharger mounting bolts with an anti-seize compound.
  3. Position the turbocharger on the exhaust manifold and hand tighten the mounting bolts.
  5. Attach the oil return line adapter to the bottom of the turbo with a new O-ring seal. Hand tighten the mounting bolts.
  7. Connect the exhaust pipe to the turbocharger and hand tighten the mounting bolts.
  9. Tighten the turbo-to-exhaust manifold bolts to 30 ft. lbs. (41 Nm). Tighten the oil return line adaptor bolts to 22 ft. lbs. (30 Nm) on all models except Quantum. On Quantum models, tighten the bolts attaching the return line to the turbocharger to 18 ft. lbs. (30 Nm), then tighten the side bolt to 18 ft. lbs. (30 Nm). Tighten the exhaust pipe bolts to 18 ft. lbs. (30 Nm).
  11. Fill the upper oil supply connection on the turbocharger with oil. This ensures proper bearing pre-lube during start up. Connect the supply line and tighten until snug.
  13. Connect the turbocharger-to-air intake manifold and air cleaner hoses.
  15. Install the heat shields.
  17. Raise the stabilizer bar to its original position and install the stabilizer bar clamps.
  19. Install the engine and transaxle covers.
  21. Connect the negative battery cable. Install a new oil filter and fill the crankcase to the proper level.
  23. When installation is complete, start the engine and allow to idle for several minutes. Do not increase engine speed above idle until the turbocharger oil supply system has had a chance to fill.