Toothed Belt

Toothed Belt

Special tools, testers and auxiliary items required

• Securing pin (3359)

• Pin wrench (T10020) or (T10004 )

• Securing pin (T10115)

• Crankshaft stop (T10050)

• Torque wrench (V.A.G 1331)

• Torque wrench (V.A.G 1332)

• Engine support bridge (10 - 222 A) with adapter (10 - 222 A /8) (change the guide ( 10 - 222 A/21) )

• Pin wrench (T10020) or (T10004 )

• Counter-holder tool (T10172)

• Pin (T10172/4)

• Spanner wrench (3387) (for engines equipped with the hydraulic tensioning system)

• Marking plate (T10008) (for engines equipped with the hydraulic tensioning system)

• A new toothed belt tensioning roller has been introduced. The tensioning roller has an additional hex socket - arrow -. Use a hex wrench instead of a spanner wrench (T10020) or ( T10004) to tension/relieve the toothed belt. The work procedure does not change due to this.

Changing the guide ( 10 - 222 A/21) for the engine support bridge ( 10 - 222 A)

The engine support bridge is needed to support the engine/transmission subassembly.

A new hole is required for securing the bracket for engine ( 10 - 222 A/8) to the guide (10 - 222 A/21).

Dimensions in mm.

- Drill a 12.5 mm dia. hole - arrow - into the guide (10 - 222 A /21).

Removing

• Adjustments to the toothed belt may generally only be performed when the engine is cold.

- Remove the engine cover and, if present, remove the upper engine noise insulation => [ Engine, Removing ] Engine, Removing.

- Remove ribbed drive belt => [ Ribbed Drive Belt ] Ribbed Drive Belt.

- Remove the ribbed drive belt tensioner.

- Remove the coolant reservoir (the coolant hoses remain connected).

- Remove the fuel filter retaining bracket.

- Mount the engine support bridge (10 - 222 A) and support the engine in installation position.

- Remove the engine mount/engine mount bracket, engine mount/longitudinal member and engine mount/longitudinal member bracket bolts - arrows - and remove the engine mount.

• The engine mount may only be removed if the engine is supported by the engine support bridge (10 - 222 A)!

• The engine mount bracket may only be loosened only when the engine mount is removed.

- Remove the upper toothed belt guard.

- Disconnect the lower charge air pipe - 1 -. Remove the bolt - 2 - and release the electrical connections - arrows -. Carefully cover or seal any open ends.

- Remove the center and right noise insulation.

- Unbolt - arrows - and remove the engine mount bracket at cylinder block.

• To loosen both upper engine mount bracket bolts, the engine must be raised slightly with the engine support bridge.

• To loosen the lower engine mount bracket bolt, the engine must be lowered slightly with the engine support bridge.

- Remove vibration damper/belt pulley.

- Remove lower and middle toothed belt cover.

- Turn crankshaft to set cylinder 1 at TDC.

• Rotate the engine only by the crankshaft.

• Turn the crankshaft in the direction of the engine far enough until the marking on the crankshaft toothed belt sprocket is positioned on the top and the arrow "4Z" - 2 - on the rear toothed belt guard is positioned across from the tabs of the sensor wheel on the hub - 1 -.

• In the illustration, the camshaft-toothed belt sprocket is shown without the toothed belt.

- Lock the hub with the rig pin ( 3359). To do this, push the rig pin through the left-sided empty slot in the bore of the cylinder head.

- Also, lock the toothed belt crankshaft sprocket with the crankshaft stop (T10050). Push the crankshaft stop from the front side of the toothed belt sprocket into the teeth.

• The marking on the toothed belt sprocket-crankshaft - 2 - and on the crankshaft stop - 1 - must align. The pin on the crankshaft stop must engage in the hole on the sealing flange.

- Mark rotational direction of toothed belt.

With Hydraulic Tensioning System

Identification:

With tensioning device for toothed belt - arrow -.

- Insert an Allen wrench into socket-head up to stop and press the tensioning roller counterclockwise in - direction of arrow -, until tensioning device of toothed belt can be secured using marking plate (T10008).

• If the Allen wrench is not inserted deep enough, the socket head could break off.

• The toothed belt tensioner is oil-dampened and must be compressed slowly by applying constant pressure.

- Loosen the nut of the tensioning roller.

- Remove the toothed belt tensioner bolts - arrows - and remove the tensioner.

- Remove toothed belt.

With Friction Dampened Tensioning System

- Loosen the bolts - arrows - of the camshaft sprockets, until the camshaft sprocket can be turned in the slots.

- Loosen the nut of the tensioning roller.

- Turn the tensioner roller using the spanner wrench (T10020) or (T10004) counterclockwise until the toothed belt tensioner roller can be locked with the securing pin (T10115).

- Now turn the tensioner roller clockwise using the spanner wrench (T10020) or (T10004) all the way until it stops and tighten the mounting bolt - 1 - hand tight.

- First, take the toothed belt from the coolant pump and then from the remaining sprockets.

Installing

• Adjustments to the toothed belt may generally only be performed when the engine is cold.

With Hydraulic Tensioning System

• Camshaft is secured with the rig pin (3359)

• Crankshaft is secured with the crankshaft stop ( T10050)

- Loosen the bolts - 1 - of the camshaft sprockets, until the camshaft sprocket can be turned in the slots.

- Turn the camshaft sprocket in its slot clockwise in - direction of arrow - onto the stop.

- Now carefully turn the eccentric pulley with the spanner wrench (3387) clockwise, until the tab on the eccentric pulley is immediately in front of the stop - B -.

- Mount the toothed belt on the camshaft sprocket, tensioning roller, toothed belt sprocket - crankshaft and then on the toothed belt sprocket - coolant pump.

- Install the toothed belt tensioner.

- Turn the eccentric pulley with the spanner wrench (3387) counterclockwise (the tab on the eccentric pulley moves toward the stop - A -), until it is possible to remove the marking plate (T10008) free of stress and when dimension - a - is less than 4 mm.

- Then turn the tensioner clockwise to release the pressure far enough (the tab moves in the direction of the stop- B -), until dimension - a - is reached.

Specified dimension - a -: 4 ± 1 mm

• Dimension - a - will get smaller while tightening the tensioner mounting nut. Adjust with a 4 mm dia. drill bit.

• If the engine is at operating temperature, dimension - a - can get smaller by 1 mm.

- Hold the tensioning roller in this position and tighten the nut on the tensioning roller as follows:

20 Nm and 45° (1/8 turn) further

- Tighten camshaft sprocket bolts - 1 - to 25 Nm.

- Remove the rig pin (3359) and the crankshaft stop (T10050).

- Turn crankshaft over twice in engine running direction and then set cyl. 1 to TDC again.

• While doing so, the crankshaft stop tab must engage in the sealing flange.

• If the crankshaft was turned past TDC for cylinder 1 and if the crankshaft stop could not engage the sealing flange, turn the crankshaft back 1/4 revolution, in order to turn crankshaft in engine running direction again to TDC for cylinder 1. It is not reliable to correct this by turning the engine against running direction to set the crankshaft stop.

- After having set the crankshaft stop (T10050 ), make sure that

- dimension - a - is attained, - the tab can be secured with the rig pin (3359).

If dimension - a - is not obtained:

- Tension the tensioner one more time. Hold the tensioner secure with the pin wrench (3387) while loosening the mounting nut and release the tension on the tensioner far enough until dimension - a - is attained.

Specified dimension - a -: 4 ± 1 mm

- Tighten the mounting nut once again to 20 Nm + 45° ( 1/8 turn).

If the hub cannot be locked:

- Pull the crankshaft stop tab out of the bore in the sealing flange and turn the crankshaft until the hub can be locked with the rig pin (3359).

- Loosen the camshaft sprocket bolts - 1 -.

- Turn the crankshaft against the engine running direction until the crankshaft stop tab is positioned shortly before the sealing flange bore - arrow -.

- Now turn the crankshaft in engine running direction until the crankshaft stop tab engages the sealing flange.

- Tighten camshaft sprocket bolts to 25 Nm.

- Remove the rig pin (3359) and the crankshaft stop (T10050).

- Continue turning crankshaft two rotations in direction of engine rotation until the crankshaft is again at TDC for cylinder 1.

• While doing so, the crankshaft stop tab must engage in the sealing flange.

• If the crankshaft was turned past TDC for cylinder 1 and if the crankshaft stop could not engage the sealing flange, turn the crankshaft back 1/4 revolution, in order to turn crankshaft in engine running direction again to TDC for cylinder 1. It is not reliable to correct this by turning the engine against running direction to set the crankshaft stop.

- Check again.

With Friction Dampened Tensioning System

• Camshaft is secured with the rig pin (3359)

• Crankshaft is secured with the crankshaft stop ( T10050)

• Tensioning roller secured with pin (T10115) and seated on right stop

• Adjustments to toothed belt may generally only be performed when the engine is cold, because the indicator position of the tensioning element changes depending on engine temperature.

- Turn the camshaft sprocket in its slots - arrows - to middle position.

- Mount the toothed belt onto the toothed belt sprocket - crankshaft, the tensioner, the camshaft sprocket and the idler roller and finally on the coolant pump toothed belt sprocket.

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

- Loosen the nut of the tensioner roller and pull out the locking pin (T10115).

- Turn the tensioner roller clockwise using the spanner wrench (T10020) or (T10004) until the indicator is located centrally in the gap of the base plate - arrow -. Make sure that the nut does not turn along with it.

- Hold the tensioner roller in this position and tighten the nut on the tensioner roller as follows:

20 Nm and 45° (1/8 turn) further

- Install the counter-holder (T10172) with pins (T10172/4) as illustrated. Push the counter-holder in - direction of arrow - and hold the camshaft sprocket pre-tensioned.

- Check if the crankshaft can be locked with the crankshaft stop (T10050).

If the crankshaft cannot be locked:

- Loosen the bolts - arrows - of the camshaft sprocket.

- Turn the crankshaft against the engine running direction until the crankshaft stop tab is positioned shortly before the sealing flange bore - arrow -.

- Now turn the crankshaft in engine running direction until the crankshaft stop tab engages the sealing flange.

- Install the counter-holder (T10172) with pins (T10172/4) as illustrated. Push the counter-holder in - direction of arrow - and hold the camshaft sprocket pre-tensioned.

- In this position, tighten the camshaft sprocket bolts - 1 - to 25 Nm.

- Remove the rig pin (3359) and the crankshaft stop (T10050).

- Continue turning crankshaft two rotations in direction of engine rotation until the crankshaft is shortly before TDC for cylinder 1.

- Check again.

Continuation for All

- Install the center and lower toothed belt guards.

- Install the belt pulley/vibration damper.

Tightening specification: 10 Nm + 90° (1/4 additional turn)

- Set engine mount bracket in place at cylinder block and fasten bolts - arrows -.

Tightening specification: 45 Nm

• Before installing engine mount bracket, insert screws in bracket.

• Before the engine mount can be installed, all bolts for the engine mount bracket must be tightened to the specified tightening specification.

- Install the engine mount/longitudinal member (replace the mount bolts).

Tightening specification: 40 Nm + 90° (1/4 additional turn)

- Align the engine mount => [ Powertrain Mount, Aligning ] Service and Repair.

- Tighten the engine mount to engine mount bracket bolts, To do so, bring contact surfaces into contact using the engine support bridge (10 - 222 A).

Tightening specification: 100 Nm

- Install the engine mount/longitudinal member bracket bolts.

Tightening specification: 25 Nm

- Install the upper toothed belt guard.

- Install the fuel filter retaining plate.

- Install coolant expansion tank.

- Install the ribbed belt tensioning element.

Tightening specification: 25 Nm

- Install ribbed drive belt => [ Ribbed Drive Belt ] Ribbed Drive Belt.

- Install the engine cover, and if equipped, the upper engine insulation => [ Engine, Removing ] Engine, Removing.

- Install the center and right noise insulation.

- Install the lower charge air pipe.