Removal and Replacement
Cylinder head, removing and installing
Removing
Installing
Special tools, testers and auxiliary items required
^ Drip tray V.A.G1306
^ Torque wrench V.A.G1332
^ Spring-type clip pliers VAS5024
^ Head gasket aligner 3450/2A
^ Removal tool 3450/3
^ Key 3452 (for polydrive cylinder head bolts) *See note
^ *The key 3452 was replaced by the socket T10070.
Special tools, testers and auxiliary items required
^ Assembly tool T10112
Removing
Requirement
^ Engine must be no more than warm to touch.
Work sequence
CAUTION!
When doing any repair work, especially in the engine compartment, pay attention to the following due to the cramped conditions:
^ Route all the various lines (e.g. for fuel, hydraulics, EVAP system, coolant, refrigerant, brake fluid and vacuum) and electrical wiring so that the original positions are restored.
^ Ensure that there is sufficient clearance to all moving or hot components.
- Check whether a coded radio is installed. If so, obtain anti-theft coding.
- With ignition switched off disconnect battery Ground strap.
- Remove engine cover.
- Drain coolant.
CAUTION!
Fuel system is under pressure! Before opening the system place a cloth around the connection. Then release pressure by carefully loosening the connection.
Engine codes AEG, AVH, AZG, BDC
- Pull fuel supply line - 3 -, fuel return line - 2 - and vacuum hose - 1 - off connections.
Engine codes BEV, BGD
- Pull off fuel supply line at connection - 1 - and collect leaking fuel with a cloth.
Note:
^ To do this slide securing ring - 2 - in union connection - 1 -
Continued for all engine codes
- Seal lines so that fuel system is not contaminated by dirt etc.
- Remove intake manifold upper part.
- Disconnect all necessary coolant, vacuum and intake hoses from intake manifold upper part/cylinder head.
- Pull off/disconnect all electrical connections/wiring as necessary from intake manifold upper part/cylinder head and lay aside.
Note:
^ Seal the intake ports in the intake manifold lower part with a clean cloth.
Engine codes AEG, AVH, AZG, BDC
- Pull fuel supply line - 1 - and fuel return line - 2 - off fuel rail.
Engine codes BEV, BGD
- Disconnect fuel supply line at connection - 1 -. To do this slide securing ring - 2 - in union connection - 3 -.
Continued for all engine codes
- Seal lines so that fuel system is not contaminated by dirt etc.
- Remove connections of coolant hoses.
- Remove suction and pressure lines for secondary air injection pump motor.
- Unbolt secondary air injection pump motor and bracket and remove.
- Disconnect front exhaust pipe with catalytic converter from manifold support.
- Remove poly V-belt.
- Remove tensioner for poly V-belt.
- Remove retainer ( ) of tensioner for poly V-belt.
- Remove toothed belt guard - upper part.
- Set camshaft pulley to TDC No. 1 cylinder by turning crankshaft. Mark on camshaft pulley must align with arrow on toothed belt guard - arrows -.
Loosen tensioning roller and remove toothed belt from camshaft pulley.
Turn crankshaft back slightly.
- Remove cylinder head cover.
- Remove upper bolt from rear toothed belt guard.
- Loosen socket head bolts in the sequence given and then remove.
Note:
^ Use socket T10070 for polydrive cylinder head bolts.
- Carefully lift cylinder head off.
Installing
Requirement
^ Pistons must not be positioned at TDC. Turn crankshaft back slightly if necessary.
Work sequence
Note:
^ There must be no oil or coolant in the cylinder head bolt pockets in the cylinder head.
^ Do not remove new cylinder head gasket from its packing until immediately before installing.
^ Handle new gasket with extreme care. Damage will cause leakage.
- Place clean cloths in cylinders so that no dirt or emery cloth particles can get in between cylinder wall and piston.
- Also prevent dirt and emery cloth particles from getting into coolant.
- Carefully clean sealing surfaces of cylinder head and cylinder block. Ensure that surfaces are not scored or scratched (if abrasive paper is used, grade must not be less than 100).
- Carefully remove metal particles, emery residue and cloths.
- To centralize, screw guide pins from 3450/2A into front outer threaded holes for cylinder head bolts.
- Install new cylinder head gasket.
- Install cylinder head, screw in 8 remaining cylinder head bolts and tighten by hand.
- Remove guide pins through bolt holes with removal tool from 3450/3. Turn removal tool counter-clockwise, until pins are free.
- Install remaining cylinder head bolts and tighten hand-tight.
- Tighten cylinder head in tightening sequence as follows:
^ Pre-tighten all bolts to 40 Nm.
^ Then tighten all bolts 90° (1/4 turn) further using a rigid wrench.
^ Finally, tighten all bolts 90° (1/4 turn) further using a rigid wrench.
The rest of the assembly is basically a reverse of the disassembly sequence.
Note:
^ When turning the camshaft the crankshaft must not be at TDC. Danger of damage to valves/piston crown.
- Install toothed belt and tension.
- Install poly V-belt tensioner.
- Tightening torque: 25 Nm
- Install Poly V-belt.
- Fill with new coolant.
- Read Diagnostic Trouble Code (DTC) memory of all control modules, correct faults and erase DTC memory Vehicle diagnosis, Testing and information system VAS 5051; Diagnosis tester; vehicle system test or Vehicle diagnosis and service information system VAS 5052; Vehicle self-diagnosis.
- Test drive vehicle and read DTC memory of all control modules again.
Note:
^ Observe applicable safety precautions during road test.