Audi A4 Workshop Service and Auto Repair Manuals

Removing and installing toothed belt - vehicles from 08.2000 onwards Special tools and workshop equipment required

t  Pin wrench -3387-

t  Locking plate -T10008-

Removing –  Release quick-release fasteners and remove engine cover panel -arrows-. –  Move lock carrier to service position → Rep. Gr.50. –  Remove poly V-belt → Chapter. –  Remove tensioner for poly V-belt → Chapter „Removing and installing bracket for ancillaries“. –  Remove viscous fan → Chapter.

–  Remove toothed belt cover (top section)   Caution The engine must only be turned at the crankshaft, in the direction of normal engine rotation (clockwise). –  Rotate crankshaft to “TDC” by turning bolt for toothed belt sprocket. l  Marking on camshaft sprocket and marking on crankshaft must be aligned to “TDC”-arrows-.

–  Counterhold by applying ring spanner to bolt for toothed belt sprocket and unbolt vibration damper.

–  Remove centre and bottom sections of toothed belt cover -arrows-.

Caution t  The toothed belt tensioner is oil-damped and can therefore only be compressed slowly by applying constant pressure. t  To avoid damage, do not apply more force than necessary when compressing the toothed belt tensioner. –  Applying constant and moderate force, use hexagon key to press toothed belt tensioner anti-clockwise in direction of -arrow- until piston of tensioner can be locked with locking plate -T10008-. –  Insert locking plate -T10008- and make sure that it remains in place.

Caution Do not to bend limit stop -A- of eccentric adjuster. –  To slacken toothed belt, loosen nut -1- on tensioning roller and turn eccentric adjuster clockwise -arrow- using pin wrench -3387-. –  Mark rotation direction of toothed belt with chalk or felt-tip pen and remove toothed belt. Installing (adjusting valve timing)   Note t  The toothed belt adjustment must also be performed as described below, even if the toothed belt has only been removed from the camshaft sprocket. t  The crankshaft must not be at “TDC” at any cylinder when the camshaft is turned. Otherwise, there is a risk of damage to valves and piston crowns. –  Fit toothed belt on crankshaft sprocket (note rotation direction). –  Install toothed belt cover (bottom section). –  Install vibration damper → Chapter. –  Check that marking on camshaft sprocket is aligned with marking on cylinder head cover -arrows-.

–  Align markings on camshaft sprocket / cylinder head cover and markings on vibration damper / toothed belt cover -arrows-. –  Make sure that toothed belt tensioner is still locked with locking plate -T10008-. –  Fit toothed belt onto coolant pump, then onto tensioning roller, and finally onto camshaft sprocket.

Tensioning   Caution Do not to bend limit stop -A- of eccentric adjuster. –  Turn eccentric adjuster anti-clockwise in direction of -arrow- using pin wrench -3387-. –  Hold eccentric adjuster in this position and pull out locking plate -T10008-.

–  Turn eccentric adjuster clockwise in direction of -arrow- until gauge -2- (dimension -a- = 8 mm, e.g. drill bit) can be pulled through between tensioning lever and housing of tensioner. –  Hold eccentric adjuster in this position and tighten nut -1- securing tensioning roller.   Caution The engine must only be turned at the crankshaft, in the direction of normal engine rotation (clockwise).

–  Turn crankshaft two rotations by turning bolt for toothed belt sprocket until the crankshaft is at “TDC” again. l  Marking on camshaft sprocket and marking on crankshaft must be aligned to “TDC”-arrows-.

–  Use gauge -2- (e.g. drill bit) to check dimension -a- between tensioning lever and housing of tensioner. l  Dimension -a- = 6 ... 10 mm.

Caution t  The toothed belt tensioner is oil-damped and can therefore only be compressed slowly by applying constant pressure. t  To avoid damage, do not apply more force than necessary when compressing the toothed belt tensioner. –  If dimension -a- is not attained: applying constant and moderate force, use hexagon key to press toothed belt tensioner anti-clockwise in direction of -arrow- until piston of tensioner can be locked with locking plate -T10008-.

–  Loosen nut -1- on tensioning roller. –  Tension toothed belt → Anchor. Assembling Installation is carried out in the reverse order; note the following: –  Install top section of toothed belt cover (make sure it engages securely on centre section of toothed belt cover). –  Install viscous fan → Chapter. –  Install poly V-belt tensioner → Chapter „Removing and installing bracket for ancillaries“. –  Install poly V-belt → Chapter.

–  Install lock carrier with attachments → Rep. Gr.50. –  Allow stop for torque reaction support to rest on rubber buffer for torque reaction support under its own weight and tighten nuts -arrows-. Tightening torques

Component	Nm
Tensioning roller for toothed belt to cylinder head	27
Toothed belt cover (bottom and centre section) to cylinder block	10 1)
Stop for torque reaction support to sump	28
l  1) Install using locking fluid; for locking fluid refer to → Parts catalogue.