Cylinder Head Disassemble (LF4)

WARNING: This page is about a different variant/trim than selected.

Special Tools

EN-8062 Valve Spring Compressor - Head Off
EN-46116 Valve Stem Seal Remover/Installer
EN-46117 Valve Stem Key Remover/Installer
EN-46119 Off-Vehicle Valve Spring Compressor Adapter
EN-46122 Camshaft Position Actuator Check-Ball Valve Remover/Installer
EN-49248 Injector Rail Assembly Remover

For equivalent regional tools, refer to Special Tools (LF4) .

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Remove the fuel rail bolts (1).
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CAUTION:
- Remove the fuel rail assembly carefully in order to prevent damage to the injector electrical connector terminals and the injector spray tips. Support the fuel rail after the fuel rail is removed in order to avoid damaging the fuel rail components.
- Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering open pipes and passages.
Remove the fuel rail and injectors (1) as an assembly using the EN-49248 remover.
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Remove the spark plugs.
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NOTE:
Ensure valve heads will not contact anything during the following step in order to avoid bending or damage.

Using an appropriately sized deep socket and a plastic hammer, lightly tap on the valve spring retainer to loosen the valve keepers.
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WARNING:
Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

CAUTION:
Do not compress the valve springs to less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

Compress the valve spring using the EN-8062 compressor and the EN-46119 adapter.
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Use the magnet of the EN-46117 remover/installer in order to remove the valve keepers.
Remove the valve spring compressor and the adapter.
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Remove the valve spring retainer.
Remove the valve spring.
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Remove the valve.
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NOTE:
NEVER reuse a valve stem oil seal.

Remove the valve stem oil seal using the EN-46116 remover/installer and discard.
Repeat these procedures for the remaining valves.
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Remove the cylinder head oil gallery expansion plugs.
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Remove the cylinder head coolant threaded plugs.
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Inspect the camshaft position actuator oil feed check valves. Damaged, restricted or clogged check valves must be replaced. If check valves are OK, disregard remaining steps which detail replacing the check valves.
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Place cylinder head on firm surface with check valves (1) facing up. Protect all cylinder head components and machined surfaces.
Using drill bit EN-46122-3, drill out top portion of check valve to expose internal check ball.
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Remove check ball (1) and check ball spring (2) from inside of check valve.
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Continue drilling remainder of check valve sleeve to a depth of approximately 19 mm (0.75 in) (a) by placing tape on drill bit as a depth gauge. It is not necessary or desirable to drill completely through the bottom of the check valve.
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Lubricate tap EN-46122-4 with lubricant included in EN-46122 remover/installer. Tap drilled out portion of check valve (1) remaining in cylinder head. Tap to full depth possible until tap bottoms out in head.
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Assemble bolt, nut, washers, and collar EN-46122-2 (1) as shown. Position collar with slightly-larger inside diameter DOWN toward the cylinder head.
Screw bolt by hand fully down into threaded check valve sleeve, then lightly tighten nut against washer.
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Hold bolt with one wrench, and use another to tighten the nut until the check valve sleeve (1) is removed from the cylinder head.
Clean check valve bore and related passages thoroughly to remove any drilling chips or other debris.