Diesel Engines - Removal and Installation of Timing Belt

GENERAL INFORMATION

CAUTION

Operations and related instructions applicable to all engines are described in the subsection Removing, Installing and Tensioning the Timing Belt. This subsection describes only the differences applicable to the TDI 1.9 L engine.

PROCEDURE

1. Loosen the V-belt tensioner pulley at the bracket.

2. Remove the brake booster vacuum pump.

3. Turn the crankshaft to bring No. 1 piston to TDC (see subsection Setting No. 1 Piston to TDC). In this position, insert the setting bar into the camshaft slot

3418. The bar prevents the camshaft from rotating. If necessary, the bar can be made by yourself.

4. Positioning the setting bar parallel to the cylinder head: Turn the crankshaft so that the end of the bar rests against the cylinder head. At the other end of the bar, measure the resulting gap with a feeler gauge. Insert a feeler gauge with a thickness equal to half of the measured gap between the bar and the cylinder head. Now turn the engine so that the bar rests on the feeler gauge. Insert a second feeler gauge of the same size between the bar and the cylinder head at the other end.

5. In the opening at the clutch housing, the TDC mark on the flywheel and the reference mark are aligned opposite each other.

6. Lock the injection pump pulley with pin AUDI–

3359. A suitable alternative pin, such as a drill bit, may be used instead of the specified pin. Loosen the mounting bolts one by one (arrows in the accompanying illustration) and replace them with new bolts. Tighten the bolts to 20 N·m.

CAUTION

Do not loosen the central bolt on the injection pump, as this may disrupt the pump adjustment. Independent adjustment of the injection pump is difficult.

7. Support the engine with a hoist, then remove the right engine mount and vibration damper. Refer to the subsection Removing, Installing and Tensioning the Timing Belt.

8. Remove the timing belt.

9. With the timing belt removed, loosen the camshaft sprocket bolt by 1/2 turn.

CAUTION

When loosening the bolt, hold the camshaft with a wrench on the flats. Do not use the setting bar as a holding tool.

10. Remove the sprocket retaining bolt. Remove the camshaft timing sprocket from the taper by tapping with a hammer on a drift through the opening in the rear timing belt cover.

11. Install the timing belt. When installing a used belt, observe its direction of rotation. The arrow marked during removal points in the direction of engine rotation, i.e. clockwise. Install the belt in the following sequence: crankshaft sprocket, idler roller, coolant pump, injection pump sprocket and tensioner roller.

12. Install the camshaft sprocket together with the belt onto the camshaft and tighten the bolt by hand. The camshaft sprocket must still be able to turn on the shaft.

13. Remove the injection pump sprocket locking pin.

14. Turn the tensioner roller clockwise with a tool, e.g. HAZET 2587, so that the mark on the tensioner roller and the lug align.

15. Tighten the tensioner roller clamping nut to 20 N·m.

16. Check again that the TDC mark on the flywheel and the basic mark align.

17. Tighten the camshaft sprocket to 45 N·m, holding the camshaft against rotation with a wrench.

18. Remove the camshaft timing gauge from the camshaft.

19. Remove pin AUDI–3359 from the injection pump sprocket.

20. Turn the crankshaft two revolutions and again stop at TDC of cylinder 1.

21. Check whether the injection pump sprocket locks with pin AUDI–

3359. If the pin does not insert, loosen the injection pump sprocket bolts and turn the hub so that the pin engages.

22. Tighten the engine support bracket to the cylinder block to 45 N·m.

23. Tighten the engine mounts.

CAUTION

Bolts undergo permanent deformation during tightening. Therefore, they must be replaced after each tightening. Tighten the engine support bracket to the mount to 60 N·m, then turn the bolt an additional 90° (1/4 turn) with a rigid wrench. Tighten the engine mounts to the body to 40 N·m, then turn an additional 90° (1/4 turn) with a rigid wrench.

24. Install the timing belt guard, vibration damper, V-ribbed belt tensioner roller and cylinder head cover.

25. Install the V-ribbed belt, refer to Removal and Installation of V-Ribbed Belt.

26. Check the start of injection of the injection pump (workshop procedure).

CAUTION

After adjusting the injection timing, tighten the injection pump pulley bolts to 20 N·m, then turn them an additional 90° (1/4 turn) with a rigid wrench. After tightening the bolts in this way, replace them with new ones every time they are loosened.