Audi Workshop Service and Repair Manuals

Removing and installing camshafts and hydraulic chain tensioner

Special tools and workshop equipment required

t	Counterhold tool -3036-

t	Torque wrench -V.A.G 1331-

t	Torque wrench -V.A.G 1332-

t	Tensioning bolt -T10092-

t	Mandrel -T40029-

t	Puller -T10055-

t	Electric drill with plastic brush attachment

t	Safety goggles

t	Sealant → Parts catalogue

Removing   Note t  Sealing surfaces at retaining frame and cylinder head may be cleaned but not machined. t  Camshaft bearings are integrated into cylinder head/retaining frame. Toothed belt must be detached before removing retaining frame. t  If retaining frame has been unfastened, oil seals of camshafts and cap at rear must be replaced. –  Move lock carrier to service position → Chapter. –  Remove toothed belt from camshaft sprocket → Chapter. –  Remove cylinder head cover → Chapter. –  Turn the crankshaft approx. 45° anti-clockwise at the toothed belt sprocket bolt so that all pistons are clear of TDC position.

–  Loosen camshaft sprocket using counterhold tool -3036-. –  Detach camshaft sprocket.

–  Unplug electrical connector -arrow- at Hall sender -G40-. –  Remove Hall sender housing and also washer and rotor for Hall sender.

–  Unplug electrical connector -2- at inlet camshaft control valve 1 -N205-. –  Unscrew earth cable -3-.   Note Disregard -item 1-.

–  Remove bolts -arrows-. –  Remove inlet camshaft control valve 1 -N205- with valve timing housing.   Note Shown in illustration from rear with engine removed.

–  Remove heat shield. To do so, slacken off bolts -1- and -2- and lift out heat shield.

–  Check TDC position of camshafts again: l  The two marks on the camshafts must be opposite the two arrows on the retaining frame.   Note Depending on the version, the inlet camshaft can be marked with an arrow -A- or a groove -B-.

If old drive chain is to be reused: –  Clean drive chain and chain sprockets of camshafts opposite the two arrows on the retaining frame and make coloured mark to identify installation position. l  The gap between the two -arrows-/coloured marks = 16 drive chain rollers. l  Notch on exhaust camshaft has a inward offset with respect to chain roller „1“.   Note Do not mark chain with a centre punch or by making a notch or similar.

Continued for all drive chains: –  Secure hydraulic chain tensioner with bolt from tensioning bolt -T10092- and nut M5 -item 1-.   Note If the retainer for the hydraulic chain tensioner is tightened excessively, this can damage the chain tensioner.

–  Working inwards, slacken off bolts of retaining frame in the sequence indicated.

–  Carefully press off retaining frame using two M6 bolts -arrows-. –  Remove retaining frame. –  Remove bolts for hydraulic chain tensioner. –  Carefully lift out camshafts with hydraulic chain tensioner and set down on a clean surface. Installing   Note Renew gaskets and seals. l  Pistons must not be at TDC. l  Make sure dirt and remnants of sealant do not drop into cylinder head. –  Remove sealant residue from retaining frame and cylinder head with rotating plastic brush or similar.   WARNING Wear safety goggles. –  Clean sealing surfaces; they must be free of oil and grease.

–  Position drive chain on camshaft chain sprockets as follows: If old drive chain is to be reused: –  Adjust the colour markings -arrows- so they are aligned.

If new drive chain is being used: –  Cams -A- of cylinder 1 must face each other.   Caution t  The stated number of rollers merely provides assistance for fitting the drive chain onto the camshafts. t  Make sure that the arrows on the retaining frame and the markings on the camshafts align when fitting the camshafts (with drive chain) in the cylinder head → Anchor.   Note Depending on the version, the inlet camshaft can be marked with an arrow -A- or a groove -B-.

l  The distance between markings -A and B- on the camshafts must be 16 drive chain rollers. The illustration shows the exact positions of the 1st and 16th rollers on the sprockets. l  Marking -A- has an inward offset with respect to chain roller -1-. Continued for all drive chains: –  Insert hydraulic chain tensioner inside drive chain (2nd mechanic required). –  Locate camshafts together with drive chain and hydraulic chain tensioner on cylinder head. –  Lubricate running surfaces of camshafts.   Note Dowel sleeves for retaining frame and hydraulic chain tensioner must be located in cylinder head. –  Tighten mountings of hydraulic chain tensioner (watch position of dowel sleeves).

–  Cut off tube nozzle at front marking (nozzle approx. 2 mm Ø).

–  Apply bead of sealant -arrows- onto clean sealing surface to underside of retaining frame as illustrated. l  Thickness of sealant bead: 2 ... 3 mm   Note Do not apply more sealant than specified, as otherwise surplus sealant could get into oil drillings or camshaft bearings and thus damage the engine. –  Fit retaining frame onto cylinder head.

–  Fix retaining frame in position with locking pin -T40029-.   Note t  No time should be allowed to elapse when fitting and securing retaining frame, as sealing surfaces start to harden as soon as they make contact. t  After fitting retaining frame, allow sealant to dry for approx. 30 minutes.

–  Tighten retaining frame evenly from the inside outwards in the sequence shown.   Note Take care to keep retaining frame straight. –  Do not tighten bolts until retaining frame makes contact with cylinder head over the full surface.

–  Pull out locking pin -T40029- using puller -T10055-. –  Remove tensioning bolt -T10092-.

–  Check correct setting of camshafts: l  The two markings on the camshafts must be opposite the two arrows on the retaining frame -arrows-.   Note t  Rotate the camshafts back or forward as necessary to align the two markings. t  Depending on the version, the inlet camshaft can be marked with an arrow -A- or a groove -B-.

–  Renewing camshaft oil seals: → Chapter „Renewing exhaust camshaft oil seal“ or → Chapter „Renewing inlet camshaft oil seal“. –  Fit end cover behind exhaust camshaft. –  Install inlet camshaft control valve 1 -N205- → Chapter.

–  Install camshaft sprocket. l  Installation position: The thinner web of the camshaft sprocket faces outwards -arrows- and the marking for TDC is visible.

–  Tighten securing bolt of camshaft sprocket (use counterhold tool -3036-). –  Install Hall sender → Item. –  Install cylinder head cover → Chapter. –  Turn crankshaft approx. 45° clockwise to TDC position via securing bolt for toothed belt sprocket. The remaining installation steps are carried out in the reverse sequence. –  Install toothed belt (adjust valve timing) → Anchor. –  Install poly V-belt → Chapter.   Note t  After installing camshafts, wait for approx. 30 minutes before starting engine. Hydraulic valve compensation elements have to settle (otherwise valves will strike pistons). t  After working on the valve gear, turn the engine carefully at least 2 rotations to ensure that none of the valves make contact when the starter is operated. –  Install lock carrier with attachments → General body repairs, exterior; Rep. gr.50.

–  Allow stop for torque reaction support to rest on rubber buffer for torque reaction support under its own weight and tighten bolts -arrows-. –  Install front bumper cover → General body repairs, exterior; Rep. gr.63. –  Check headlight adjustment → Booklet803. Tightening torques

Component	Nm
Camshaft adjuster to camshaft	100
Hydraulic chain tensioner to cylinder head	10
Retaining frame to cylinder head	8
Camshaft sprocket to camshaft	65
Hall sender rotor to camshaft	25
Hall sender housing to cylinder head	10
Stop for torque reaction support to lock carrier	28