Renew timing chain for camshaft drive: VW 1.6 (AHL)

Special tools, test equipment and accessories required

Camshaft lock 3436
Torque wrench V.A.G 1331 (5...50 Nm)
Riveting tool 3442
Assembly wedges 3409
Open-end spanner 3437
Spark plug spanner 3122 B

Sequence of operations

Remove the intake hose -1- on the throttle valve control unit.
Unscrew the spark plug cover -2-.

Unscrew the spark plugs with the spark plug spanner 3122 B.
Removing the spark plug cover => page
15-12.
Pull off coolant hoses from thermostat housing.
Unscrewing the thermostat housing from the upper timing case cover => page
19-5
, Parts of the coolant system on the engine side.

Note:

When removing the upper timing case cover secure seal -arrow- to prevent it from falling down.

Unscrew upper timing case cover.

Note:

Use open-end spanner 3437 to steady the camshafts.

Loosen bolts of the camshaft sprockets.

Position crankshaft at securing bolt of vibration damper on marking 20° after TDC in direction of rotation of the engine.

Removing chain tensioner =>page
13-16.

Unscrew the securing bolts and remove upper slide rail -1-.

Fix the camshafts at the checking bores with the camshaft lock 3436.

Wedge the timing chain -1- in the cylinder head -3- with the assembly wedges 3409.
Cover the timing case with a cleaning rag -4-.
Grind both link pins on a chain link -2- of timing chain -1-.

Remove the outer lug -1-, centre lug -2- and chain link -3-.

Hook up the new timing chain with a chain link -1- in the old timing chain -2-.

Note:

Ensure that the ends of the timing chain do not fall into the timing case after the assembly wedges 3409 are removed.

Remove assembly wedges 3409.
Unscrew the camshaft sprockets -3-.
Change the timing chain by slowly turning the crankshaft in direction of rotation of the engine.

Note:

While turning, keep both ends of the chain under slight tension.

Position crankshaft at securing bolt of vibration damper on marking 20° after TDC in direction of rotation of the engine.
Unhook old timing chain.

Fix camshafts with the camshaft lock 3436.
Mount the camshaft sprockets -1- on the camshafts.

Note:

The internal Torx bolts for the camshaft sprockets are to be renewed before re-installing.

Place timing chain on camshaft sprockets -3- and insert a new chain link -2- with a new centre lug -1- in the timing chain.

Caution!
Ensure that the camshaft lock 3436 is not loaded when tightening the internal Torx bolts. Use open-end spanner 3437 to steady the camshafts.
Tighten camshaft sprockets -3- in two stages.
1. Pre-tighten with torque wrench:
Stage I = 20 Nm

2. Continue turning with rigid wrench:
Stage II =1/4 turn (90 °)
Insert a new outer lug -1- in the riveting tool 3442 -arrow-.

Place the riveting tool 3442 on the chain link and press in outer lug onto stop.

Change over the punch of the riveting tool 3442 -arrow-.

Place the riveting tool 3442 on the chain link and rivet the link pins individually.
Tightening torque of spindle: 35 Nm
Check the link pin rivets (by visual inspection) and re-rivet these if necessary.

Remove camshaft lock 3436.
Turn the engine slowly.
Checking valve timing => page
13-15.

Tighten upper slide rail -1-.
Tightening torque: 10 Nm
Installing chain tensioner => page
13-16.
Installing upper timing case cover => page
15-1
, Service cylinder head.
Screw in spark plugs.
Tightening torque: 25 Nm
Installing cylinder head cover and throttle valve control unit =>page
15-12
, Removing and installing cylinder head cover.