Setting Camshaft Timing

Setting Camshaft Timing:

Setting the camshaft timing is necessary whenever the cam drive system has been disturbed such that the relationship between any chain and sprocket has been lost. Even when only one sprocket is involved, the following procedure should be observed since one crankshaft rotation will not provide conditions where the correct timing can be confirmed.

The camshafts and the crankshaft events are correctly timed when the crank sprocket and the intermediate shaft sprocket have their timing marks aligned and all four camshaft drive pins are perpendicular (90°) to the cylinder head surface. In order to establish this condition, follow the following procedure:

^ Tools Required
- J 39411 Flywheel Holder
- J 39946 Crankshaft Rotation Socket






1. Install the crankshaft sprocket drive key. If necessary, tap the key in place with a small hammer until it bottoms on the crankshaft.
2. Align the timing marks of the intermediate and crankshaft sprockets. The marks should be aligned vertically in the installed position.
3. Install the primary timing chain on the drive sprockets.
4. Make sure that piston number one is at Top Dead Center (TDC) and the crankshaft keyway is at the one o'clock position.






5. Install the primary timing chain, intermediate, sprocket and crankshaft sprocket as an assembly onto their respective shafts. Use the J 39946 in order to align the crankshaft key with the drive sprocket.






6. Install the intermediate sprocket retaining bolt.
^ Tighten the intermediate sprocket shaft bolt to 60 Nm (44 ft. lbs.).

NOTICE: Refer to Fastener Notice in Service Precautions.






7. Collapse the primary drive chain tensioner using the following procedure:
7.1. Rotate the ratchet release lever counterclockwise and hold.
7.2. Collapse the tensioner shoe and hold.
7.3. Release the ratchet lever and slowly release the pressure on the shoe.






8. As the ratchet lever moves to its first click, hold the tensioner shoe inward and insert a pin through the hole in the release lever.
9. The locked ratchet mechanism should hold the shoe in a collapsed position.






10. Install the primary drive chain tensioner and retaining bolts.
^ Tighten the primary drive chain tensioner bolts to 25 Nm (18 ft. lbs.).

IMPORTANT: Make sure the tensioner release lever faces toward you before tightening.

11. Remove the retaining pin allowing the tensioner shoe to extend.
12. Check the timing marks to make sure they are aligned vertically.






13. Lock the flywheel in order to prevent engine rotation. Use the J 39411.






14. Install all four secondary camshaft drive chain guides, if necessary.
^ Tighten the secondary camshaft guide bolts to 25 Nm (18 ft. lbs.).






15. Install the secondary chain guide access plugs in the front of the cylinder head.
^ Tighten the chain guide access plugs to 4.5 Nm (39 inch lbs.).

16. Route the secondary drive chain for the left hand cylinder head over the inner row of the intermediate shaft teeth.
17. Route the secondary drive chain over the chain guide.






18. Install the exhaust camshaft sprocket so that the camshaft drive pin engages the sprocket notch marked LE (left head exhaust). There should be no slack in the lower section of the chain. The camshaft drive pin must be perpendicular (90°) to the cylinder head face.






19. Install the intake camshaft sprocket into the chain so that the sprocket notch marked LI (left head intake) engages the cam drive pin. The cam drive pin must be perpendicular to the head face. A hex is cast into the camshafts behind the lobes for cylinder 1 (or 2, left hand) so that an open end wrench may be used in order to provide minor repositioning of the camshafts.
20. Loosely install the intake and exhaust camshaft sprocket retaining bolts.






21. Collapse the secondary drive chain tensioners; using the following procedure:
21.1. Rotate the ratchet release lever counterclockwise and hold.
21.2. Collapse the tensioner shoe and hold.
21.3. Release the ratchet lever. Slowly release the pressure on the shoe.






22. As the ratchet lever moves to its first click, hold the tensioner shoe inward and insert a pin through the hole in the release lever.
23. The locked ratchet mechanism should hold the shoe in a collapsed position.






24. Install the secondary drive chain tensioners.
25. Install the secondary drive chain tensioner retaining bolts.
^ Tighten the secondary drive chain tensioner bolts to 25 Nm (18 ft. lbs.).
^ Tighten the camshaft sprocket bolts to 120 Nm (90 ft. lbs.).

IMPORTANT: Make sure the tensioner release lever faces toward you before tightening.






26. Route the secondary drive chain for the right hand cylinder head over the outer row of the intermediate shaft teeth. Repeat steps 3 through 9 for right hand camshaft. Right hand camshaft sprockets are identified RI (right intake) and RE (right exhaust). In addition the RE sprocket must contain the camshaft position sensor pickup.
27. Install the camshaft position sensor.
^ Tighten the camshaft position sensor retaining bolt to 10 Nm (89 inch lbs.).

28. Install the oil pump. Refer to Oil Pump Replacement.
29. Install the front cover. Refer to Engine Front Cover Replacement.
30. Install both of the camshaft covers. Refer to Camshaft Cover Replacement (Left) and Camshaft Cover Replacement (Right).
31. Install the front engine mount. Refer to Engine Mount Replacement.