Audi Workshop Service and Repair Manuals

Removing and installing cylinder head Special tools and workshop equipment required

t  Puller -T40039- Removing   Caution Observe notes on procedure for disconnecting the battery → Electrical system; Rep. gr.27. –  Disconnect earth wire at battery with ignition switched off. –  Drain off coolant → Chapter. –  Move lock carrier to service position → Chapter.

–  Loosen nuts on clamp -arrows-. –  Push the clamp back in order to separate the exhaust system.   Note To avoid any damage, the flexible joint in the front exhaust pipe must not be bent more than 10°.

–  Unscrew nut -arrow- at bracket for front exhaust pipe.

–  Disconnect air pipes -1- and -2-. –  Disconnect hose from air pipe on underside.

–  Unplug electrical connector -1- at air mass meter -G70-. –  Disconnect hose -2-, if fitted. –  Remove fastener -3- and detach air cleaner housing.

–  Unfasten catalytic converter/exhaust manifold connection -arrows-.   Note Unscrew nuts from catalytic converter side. –  Detach catalytic converter from exhaust manifold. –  Remove coolant pipe (top) → Chapter. –  Remove intake manifold → Chapter.

–  Unplug electrical connector -1- at coolant temperature sender. –  Unplug electrical connector -2- at inlet camshaft control valve 1 -N205-. –  Unscrew earth cable -3-. –  Move wiring harness clear. –  Detach rear coolant hose from cylinder head. –  Remove toothed belt from camshaft sprocket → Chapter.

–  Remove bolts -1-. –  Unplug electrical connectors -2- from ignition coils and move wiring duct clear.

–  Disconnect crankcase breather hose -1- at cylinder head cover. –  Remove ignition coils -2-.   Note

Use puller -T40039- to remove ignition coils.

–  Remove cylinder head cover bolts in the sequence -16 ... 1-. –  Remove cylinder head cover.

–  Remove cylinder head bolts in the sequence: -1 ... 10-. –  Remove the cylinder head with the assistance of a 2nd mechanic. Installing   Note t  Cylinder heads which have cracks between the valve seats or between a valve seat insert and the spark plug thread can be re-installed without reducing service life, provided the cracks are only slight and do not exceed a maximum of 0.3 mm in width, and no more than the first 4 turns of the spark plug threads are cracked. t  Renew the cylinder head bolts. t  Renew self-locking nuts and bolts when performing assembly work. t  Renew bolts which are tightened to a specified angle as well as oil seals and gaskets. t  Carefully remove any sealant residue from the cylinder head and cylinder block. Ensure that no long scores or scratches are made on the surfaces. t  Carefully remove any remaining emery and abrasive material. t  No oil or coolant must be allowed to remain in the blind holes for the cylinder head bolts in the cylinder block. t  When installing an exchange cylinder head with the camshafts fitted, the contact surfaces between bucket tappet and cam running surface must be oiled after installation of the cylinder head. t  The plastic protectors fitted to protect the open valves must only be removed immediately before fitting the cylinder head. t  Do not remove new cylinder head gasket from packaging until it is ready to be fitted. t  Handle gasket very carefully. Damage to the silicone coating or the indented area will lead to leaks. t  When fitting a new cylinder head or cylinder head gasket, drain off all the old coolant and refill with new coolant. t  Secure all hose connections with the correct type of hose clips (same as original equipment) → Parts catalogue.

–  Set camshaft to TDC -top arrow- before fitting cylinder head. –  Make sure that crankshaft is in TDC position -bottom arrow-; turn crankshaft via toothed belt sprocket bolt if necessary.

–  Fit cylinder head gasket. l  Note position of centring pins in cylinder block -arrows-. l  Check installation position of cylinder head gasket; the Part No. should be legible from inlet side. –  Fit cylinder head. –  Insert and hand-tighten cylinder head bolts.

–  Tighten cylinder head bolts in 3 stages in the sequence indicated:

Stage	Tightening
I	–  Tighten with torque wrench to 40 Nm.
II	–  Turn 90° (1/4 turn) further using a rigid wrench.
III	–  Turn 90° (1/4 turn) further using a rigid wrench.

Note Cylinder head bolts do not have to be torqued down again later after repair work. Remaining installation steps are carried out in reverse sequence; note the following: –  Install cylinder head cover → Chapter. –  Install toothed belt (adjust valve timing) → Anchor. –  Install vibration damper → Chapter. –  Install poly V-belt → Chapter. –  Install intake manifold → Chapter. –  Install coolant pipe (top) → Chapter. –  Install front exhaust pipe together with catalytic converter → Chapter. –  Align exhaust system so it is free of stress → Chapter.

–  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. –  Connect battery. Procedures required → Electrical system; Rep. gr.27. –  Check oil level → Chapter.   Note If engine oil is contaminated, perform oil change → Booklet803. –  Fill cooling system with fresh coolant → Anchor. –  Check headlight adjustment → Booklet803. Tightening torque

Component		Nm
Stop for torque reaction support to lock carrier		28