Crankshaft seals — replacement (Audi 100 C3)

Front crankshaft oil seal

1. Remove the toothed drive belt and crankshaft sprocket (see Chapter 6).

2. The seal can be replaced without removing the oil pump by punching or drilling two small holes diagonally in it. Screw self-tapping screws into the holes and, pulling the screws with pliers, remove the seal.

3. Wrap the end of the crankshaft with masking tape to prevent damage to the new seal. Dip the new seal in engine oil and press it into the oil pump housing using a wooden block or socket. Make sure the seal is oriented with the flat side facing out. If there is a deep groove in the seal contact area on the end of the shaft, install the new seal slightly deeper so that its sealing lip is against the unworn portion of the shaft (see illustrations).





4. Remove the adhesive tape.



5. Install the toothed drive belt and crankshaft sprocket (see Chapter 6).

Rear crankshaft oil seal (at the flywheel)

6. The seal is mounted in the housing and cannot be replaced separately. First remove the flywheel/drive plate (see Chapter 13), then remove the tray (see Chapter 15).

7. Unscrew the mounting bolts and remove the casing together with the oil seal from the cylinder block (see illustration). Remove the gasket from the mounting pins on the block.



8. Clean the surfaces of the block and crankshaft.

9. Install a new oil seal housing gasket onto the cylinder block (see illustration).



10. The new oil seal housing is equipped with a protective sleeve that is installed onto the end of the shaft before installing the oil seal/housing assembly. Place the housing assembly onto the end of the crankshaft and push it onto the dowel pins (see illustration).





11. Carefully remove the protective sleeve, making sure that the sealing lips of the oil seal are correctly seated on the crankshaft (see illustration).



12. Install the bolts and tighten them to the torque specified in the Specifications.

13. Install the tray (Chapter 15) and flywheel/drive disc (Chapter 13).