Timing Chain & Sprockets - Removal

REMOVAL

Special Tools:











CAUTION: The magnetic timing wheels (1) must not come in contact with magnets (pickup tools, trays, etc.) or any other strong magnetic field. This will destroy the timing wheels ability to correctly relay camshaft position to the camshaft position sensor.







CAUTION: When the timing chains are removed and the cylinder heads are still installed, DO NOT rotate the camshafts or crankshaft without first locating the proper crankshaft position. Failure to do so will result in valve and/or piston damage.

NOTE: The Variable Valve Timing (VVT) assemblies (Phasers) and Oil Control Valves (OCVs) can be serviced without removing the engine timing cover Variable Valve Timing Assembly - Removal .

1. Disconnect and isolate the negative battery cable.
2. Remove the air cleaner housing assembly and upper intake manifold Intake Manifold - Removal
3. Remove the cylinder head covers Cylinder Head Cover(s) - Removal
4. Remove the spark plugs Spark Plug - Removal.
5. Raise and support the vehicle Maintenance.
6. Drain the cooling system Service and Repair.
7. Remove the oil pan, accessory drive belts, crankshaft vibration damper and engine timing cover Engine Timing Cover(s) - Removal

NOTE: Take this opportunity to measure timing chain wear Measuring Timing Chain Wear






CAUTION: When aligning timing marks, always rotate engine by turning the crankshaft. Failure to do so will result in valve and/or piston damage.

8. Rotate the crankshaft CW to place the number one piston at TDC on the exhaust stroke by aligning the dimple (4) on the crankshaft with the block/bearing cap junction (5). The left side cam phaser arrows (2) should point toward each other and be parallel to the valve cover sealing surface (3). The right side cam phaser arrows (7) should point away from each other and the scribe lines (9) should be parallel to the valve cover sealing surface (8).

CAUTION: Always reinstall timing chains so that they maintain the same direction of rotation. Inverting a previously run chain on a previously run sprocket will result in excessive wear to both the chain and sprocket.

9. Mark the direction of rotation on the following timing chains using a paint pen or equivalent to aid in reassembly:
- Left side cam chain
- Right side cam chain
- Oil pump chain
- Primary chain





10. Reset the RH cam chain tensioner by pushing back the tensioner piston and installing Tensioner Pin (1).





11. Reset the LH cam chain tensioner by lifting the pawl (1), pushing back the piston (2) and installing Tensioner Pin (3) Service and Repair.





12. Remove bolts (2) and the timing gear splash shield (1).





13. Disengage the oil pump chain tensioner spring (3) from the dowel pin (2) and remove the oil pump chain tensioner (1).
14. Remove the oil pump sprocket T45 retaining bolt (4) and remove the oil pump sprocket (5) and oil pump chain (6).






NOTE: Minor rotation of a camshaft (a few degrees) may be required to install the camshaft phaser lock.

15. Install the RH Camshaft Phaser Lock (5).
16. Loosen both the intake oil control valve (2) and exhaust oil control valve (7).
17. Remove the RH Camshaft Phaser Lock (5).
18. Remove the oil control valve (2) from the right side intake cam phaser.
19. Pull the right side intake cam phaser off of the camshaft and remove the right side cam chain.
20. If required, remove the oil control valve (7) and pull the right side exhaust cam phaser off of the camshaft.






NOTE: Minor rotation of a camshaft (a few degrees) may be required to install the camshaft phaser lock.

21. Install the LH Camshaft Phaser Lock (4).
22. Loosen both the intake oil control valve (6) and exhaust oil control valve (2).
23. Remove the LH Camshaft Phaser Lock (4).
24. Remove the oil control valve (2) from the left side exhaust cam phaser.
25. Pull the left side exhaust cam phaser off of the camshaft and remove the left side cam chain.
26. If required, remove the oil control valve (6) and pull the left side intake cam phaser off of the camshaft.





27. Reset the primary chain tensioner (5) by pushing back the tensioner piston and installing Tensioner Pin (3). Remove two T30 bolts (4) and remove the primary chain tensioner.
28. Remove the T30 bolt (1) and the primary chain guide (2).





29. Remove the idler sprocket T45 retaining bolt (2) and washer (3).
30. Remove the primary chain, idler sprocket and crankshaft sprocket as an assembly.





31. If required, remove two T30 bolts (6) and the LH cam chain tensioner (5).
32. If required, remove two T30 bolts (4) and the LH cam chain guide (2) and tensioner arm (1).





33. If required, remove two T30 bolts (4) and the RH cam chain tensioner (3).
34. If required, remove three T30 bolts (2) and the RH cam chain guide (1) and tensioner arm (6).
35. Inspect all sprockets and chain guides. Replace if damaged.