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

Remove the timing chain RH. Ref. to MECHANICAL (H4DOTC)>TIMING CHAIN ASSEMBLY>REMOVAL>TIMING CHAIN RH .
Using the ST and by turning the crankshaft, align the key of the crankshaft, the alignment mark (protrusion) of the intake cam sprocket LH and the alignment mark (protrusion) of the exhaust cam sprocket LH to the positions as shown in the figure.
Preparation tool:

ST: CRANKSHAFT SOCKET (18252AA000)

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When the cam sprocket LH is removed, and the cam carrier LH is disassembled
NOTE: Follow also steps below when the cam sprocket LH is removed, and the cam carrier LH is disassembled.
1. Using the ST, loosen the bolts which hold the cam sprocket LH.
CAUTION: In order to prevent damage on each component, be careful not to loosen the bolts too much.

Preparation tool:

ST: SOCKET (18270KA010)

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Push up the chain tensioner lever LH as shown in the figure, and insert a stopper pin (clips, etc.) with a diameter of 1.2 mm (0.0472 in) or less or a hex wrench with a diameter of 1.2 mm into the stopper pin hole in the chain tensioner LH to secure the plunger (A).

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Remove the chain tensioner LH, and remove the chain tensioner lever LH (A).

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Remove the O-ring from the cylinder block LH.

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Remove the chain guide LH, and remove the timing chain LH (A).
CAUTION:
- If the timing chain LH is not installed, the exhaust camshaft LH is kept at zero- lift position. All cams on the exhaust camshaft LH are not pressing down the roller rocker arm (exhaust valve). (Under this condition, exhaust valves remain unlifted.)
- Intake camshaft LH is kept at lift position. All cams on the intake camshaft LH are pressing down the roller rocker arm (intake valve). (Under this condition, intake valves remain lifted.)
- Intake camshaft LH and exhaust camshaft RH can be independently rotated with the timing chain LH removed. When the exhaust camshaft LH is turned, the valve heads contact each other and valve stem may bend as described in above. Do not turn the exhaust camshaft LH to the outside of range of zero-lift (in range where it can be turned lightly by hand).
- The #4 piston is located near TDC. If the intake camshaft LH is turned, the valve and the piston may contact and valve stem may bend. Do not turn the intake camshaft LH at this time.