Cylinder Head, Remove and Install (16 LZ2 and 20 NEJ)
 Important! Only remove cylinder head when engine is cold - room temperature.
 Remove, Disconnect Remove lower coolant hose from radiator. Collect escaping coolant. Remove or detach all wiring harness plugs and hose connections from intake manifold - see operation "Intake Manifold, Remove and Install (16 LZ2)" or "Intake Manifold, Remove and Install (20 NEJ)". Remove front toothed belt cover - see operation "Front Toothed Belt Cover, Remove and Install (16 LZ2 and 20 NEJ). Remove support (1) and shackle (2) with wiring harness bracket (3) from intake manifold and from alternator. Release lower alternator fastening bolt and tilt alternator backwards. | 
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Remove, Disconnect Remove coolant hoses (1) and (2) from thermostat housing. Remove upper coolant hose from coolant outlet connection. Disconnect spark plug connectors. For 20 NEJ: Remove DIS ignition module with DIS ignition module bracket from cylinder head and from camshaft housing. Remove camshaft housing cover from camshaft housing. Detach front exhaust pipe from exhaust manifold - see operation "Exhaust Manifold, Remove and Install". | 
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 Adjust Before removing the toothed belt, at the fastening bolt of the toothed belt drive gear the crankshaft must be turned slowly and smoothly in direction of engine rotation 90 ° (dimension I) in front of the TDC mark. Loosen fastening bolt of toothed belt tension roller and turn adjustment eccentric in direction of arrow (clockwise) until the pointer (1) is at left stop.
Remove, Disconnect Mark running direction of the toothed belt for identification and remove toothed belt. Remove camshaft sprocket - counterhold at hex of camshaft with an open-ended wrench. Remove fastening bolts of rear toothed belt cover from camshaft housing. | 
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Remove, Disconnect Release fastening bolts in removal order shown with KM-2355, first 1/4 then 1/2 turn and remove. Remove camshaft housing from cylinder head. Remove rocker arms, thrust pieces and hydraulic valve lifters - note allocation. Remove cylinder head from cylinder block.
 Clean Remove gasket remnants. Clean sealing surfaces, bores and threads of cylinder head bolts. Notice: If the cylinder head is to be checked or modified, all the outer attaching parts must be removed from the cylinder head.
 Inspect Check cylinder head and cylinder block for plane surface - see operations "Cylinder Head, Check for Plane Surface" and "Cylinder Block, Check for Plane Surface".
 Install, Connect Position new cylinder head gasket with designation "OBEN/TOP" upwards and pointing to engine timing side. | 
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Install, Connect Place cylinder head on cylinder block. Insert hydraulic valve lifter, thrust pieces and cam followers lightly with MoS 2 lubricating paste (grey) - note allocation. Apply a bead of adhesive sealing compound (black) to sealing surface of cylinder head. Place camshaft housing on cylinder head. Attach cylinder head and camshaft housing to cylinder block with new fastening bolts. Tighten fastening bolts in installation order shown with KM-2355, use torque wrench and KM-470-B - tightening torque 25 Nm / 18 lbf. ft. + 90 ° + 90 ° + 90 ° . Attach front exhaust pipe to exhaust manifold - see operation "Exhaust Manifold, Remove and Install". Attach rear toothed belt cover to camshaft housing - 6 Nm / 4 lbf. ft. Attach camshaft sprocket to camshaft - counterhold with an open-ended wrench at camshaft hex - tightening torque 45 Nm / 33 lbf. ft. Install camshaft housing cover at camshaft housing - tightening torque 8 Nm / 6 lbf. ft. | 
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Install, Connect Attach coolant hoses to thermostat housing. Attach upper coolant hose to coolant outlet flange. Attach lower coolant hose to radiator. For 20 NEJ: Attach DIS ignition module with DIS ignition module bracket to cylinder head and to camshaft housing - tightening torque 15 Nm / 11 lbf. ft. Connect spark plug connectors. Attach support (1) and shackle (2) with wiring harness bracket (3) to intake manifold and to alternator - tightening torque 20 Nm / 15 lbf. ft. Tighten lower alternator fastening bolt - tightening torque 35 Nm / 26 lbf. ft. Install toothed belt - see operation "Toothed Belt, Remove and Install (16 LZ2 and 20 NEJ)". Attach all wiring harness plugs and hose connections to intake manifold - see operation "Intake Manifold, Remove and Install (16 LZ2)" or "Intake Manifold, Remove and Install (20 NEJ)".
Inspect Top up cooling system - see operations "Cooling System, Top up and Bleed" and "Cooling System, Check for Leaks". |
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