Toothed Belt

Toothed Belt

Special tools, testers and auxiliary items required

• Diesel Injection Pump Locking Pin (3359)

• Crankshaft Stop (T10050)

• Counterhold Tool (T10172)

• Special Wrench, Long Reach (T10264)

• Locking Tool (T10265)

• Torque Wrench (5-50 Nm) (V.A.G 1331)

• Torque Wrench (40-200 Nm) (V.A.G 1332)

Removing

• The toothed belt may be adjusted only when the engine is cold because the position of the pointer on the tensioner will change due to the temperature of the engine.

- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.

- Remove the fuel filter.

- Remove the auxiliary fuel pump/fuel pump 2.

- Disconnect the connector from the engine coolant temperature sensor on radiator outlet, open the clips - arrows - and remove the toothed belt guard.






- Remove the right front wheel housing liner.

- Remove the ribbed belt. Refer to => [ Ribbed Belt ] Ribbed Belt.

- Remove the vibration damper.

- Remove the lower and center toothed belt guard bolts - arrows - and remove the nut on the coolant pipe - 1 -.






- Rotate the engine to Top Dead Center (TDC) and secure the crankshaft toothed belt gear using the crankshaft stop (T10050). Push the crankshaft stop from the front side of the toothed belt gear into the teeth. The toothed segment of the camshaft gear must be in the "12 o'clock" position.






• The marks on the crankshaft toothed belt gear - 2 - and the crankshaft stop (T10050) - 1 - must align. The pin on the crankshaft stop (T10050) must engage in the hole on the sealing flange.

- Mark the rotational direction of the toothed belt.

- Loosen the bolts - 1 - on the camshaft gear.






- Loosen the coolant pipe bolt - 1 - and then the bolts for the high pressure pump toothed belt gear - 2 -.






- Loosen the nut - 1 - on the toothed belt tensioner.

- Turn the tensioner eccentric pulley using the special wrench, long reach (T10264) counterclockwise - arrow -, until the locking tool (T10265) can lock the tensioner.






- Now, turn the tensioner eccentric pulley clockwise - arrow - all the way and tighten the nut - 1 - hand tight.






- First, remove the toothed belt from the idler pulley and then from the remaining gears.

Installing

• The toothed belt may be adjusted only when the engine is cold because the position of the pointer on the tensioner will change due to the temperature of the engine.

• The engine mount bracket must be removed in order to replace the toothed belt tensioner. Refer to=> [ Engine Mount Bracket ] Engine Mount Bracket.

• Replace the bolts for the camshaft and high pressure pump toothed belt gears.

• The locking tool (T10265) must be inserted in the tensioner and the roller must be secured on the right stop.

• Secure the crankshaft using the crankshaft stop (T10050).

• Rotate the camshaft hub with the counter-hold tool (T10172) and adapters (T10172/4) until it can be secured in place. Use at least one bolt - 1 - tightened hand tight to do that.

- Secure the camshaft hub using the diesel injection pump locking pin (3359). To do this, push the pin through the empty outer slot and into the cylinder head bore.






- Loosen the bolts, which were tightened hand tight.

• If necessary, rotate the high pressure pump hub with a screwdriver on the bolt heads until it can be secured.

Positioning the High Pressure Pump Hub





- Secure the high pressure pump hub using the diesel injection pump locking pin (3359). To do that, slide the pin into the hole outside the toothed belt gear.






- Rotate the camshaft gear and high pressure toothed belt gear clockwise in their slots as far as the stop.

- Install the toothed belt on the crankshaft gear, the camshaft gear, the coolant pump toothed belt gear and the high pressure pump toothed belt gear.

- Lay the toothed belt on the tensioner.

- Loosen the tensioner nut and remove the locking tool (T10265).

• Make sure the tensioner is properly positioned in the rear toothed belt guard - arrow -.






- Carefully turn the tensioner eccentric pulley clockwise using the special wrench, long reach (T10264). The pointer - 2 - must be somewhat above the center of the gap in the base plate. This will be corrected when pre-tensioning.






Make sure the nut - 1 - does not rotate with it.

- Hold the tensioner in this position and tighten the nut as follows: Continue turning to 20 Nm + an additional 45° (1/8) turn.

- Position the counterhold tool (T10172) as illustrated. Push the counterhold tool (T10172) in the - direction of the arrow - and hold the camshaft gear pre-tensioned.






- First, tighten the bolts - 1 - for the camshaft gear and for the high pressure pump toothed belt gear hand tight. Then tighten them again to 20 Nm.

- Remove the diesel injection pump locking pin (3359) and the crankshaft stop (T10050).

- Rotate the crankshaft 2 revolutions further in engine rotation direction and just up to TDC for cylinder 1.

- Install the crankshaft stop (T10050) on the crankshaft toothed belt gear again.

- Now, rotate the crankshaft in engine rotation direction until the crankshaft stop tab - arrow - engages in the sealing flange.






• In the following check, only the camshaft and crankshaft are secured. The peg position for the high pressure pump hub is very difficult to find again. A small deviation - arrow - does not affect engine operation.






- Check if:

• The camshaft hub can be secured using the diesel injection pump locking pin (3359).

• The pointer on the tensioner points to the center or a maximum of 5 mm to the right of the gap in the base plate.

If the camshaft hub cannot be secured:

- Pull the crankshaft stop (T10050) toward the back until the tab opens the hole.

- Rotate the crankshaft opposite the engine rotation direction until it is slightly past TDC.

- Now, rotate the crankshaft slowly in engine rotation direction until the camshaft hub can be secured.

- After securing, loosen the bolts on the camshaft toothed belt gear.

If the crankshaft stop (T10050) tab is to the left of the hole:

- Rotate the crankshaft in engine rotation direction until the crankshaft stop tab engages in the sealing flange.






- Tighten the bolts for the camshaft toothed belt gear hand tight. Then tighten them to 20 Nm.

If the crankshaft stop (T10050) tab is to the right of the hole:

- Rotate the crankshaft slightly opposite the engine rotation direction.

- Now, rotate the crankshaft in engine rotation direction until the crankshaft stop tab engages in the sealing flange.

- Tighten the bolts for the camshaft toothed belt gear hand tighten. Then tighten them to 20 Nm.

Continuation for All

- Remove the diesel injection pump locking pin (3359) and the crankshaft stop (T10050).

- Rotate the crankshaft 2 revolutions further in engine rotation direction and just up to TDC for cylinder 1.

- Check again.

- Now, it must be possible to install the camshaft hub. Tighten the bolts as follows:

• Camshaft gear: Tighten the bolt an additional 45° (1/8). Counter hold using the counterhold tool (T10172) and adapters (T10172/4).

• High pressure pump gear: Tighten the bolt an additional 90° (1/4) turn. Counter hold using the counterhold tool (T10172) and adapters (T10172/8).






- Install the lower and center toothed belt guard.

- Install the vibration damper: Tightening specification: 10 Nm + an additional 90° (1/4) turn.

- Install the ribbed belt. Refer to => [ Ribbed Belt ] Ribbed Belt.

- Install the upper toothed belt guard.

Further installation is in the reverse order of removal. Note the following:

• Make sure the fuel hoses are secure.

• Do not interchange the supply and return lines (the return line is blue or has a blue mark, the supply line is white).

- Install the wheel housing liner.

- Install the noise insulation.