Removal
Exploded View (Righthand shown, lefthand similar):
NOTE:
- If the timing chain guides, timing chain tensioner arms or timing chains show premature wear or damage, also replace the camshaft damper.
1. Remove engine front cover.
2. Rotate crankshaft keyway to 11 o'clock location to position crankshaft at Top Dead Center (TDC) No. 1 cylinder.
3. Verify alignment arrows on camshafts are aligned. If arrows are not aligned, rotate crankshaft one complete revolution.
4. Rotate crankshaft to position crankshaft keyway to three o'clock location. This will position righthand cylinder head camshafts to neutral position (base circle).
5. Remove righthand (RH) timing chain tensioner retaining bolts, and RH timing chain tensioner.
CAUTION:
- Cylinder head camshaft journal caps and cylinder heads are numbered to ensure that they are assembled in their original positions. If removed, keep camshaft journal caps from each cylinder head together. Do not mix with camshaft journal thrust caps from another cylinder head.
- Remove the cylinder head camshaft journal thrust caps first to ensure damage to cylinder head camshaft journal thrust caps do not occur.
6. Remove cylinder head camshaft journal thrust cap retaining bolts and thrust caps from RH cylinder head.
Camshaft journal cap bolt removal sequence:
7. Loosen remaining RH cylinder head camshaft journal cap bolts in the sequence shown, seven to eight revolutions, in several passes, to allow camshafts to be raised from RH cylinder head. Do not remove bolts completely.
Exploded View (Righthand shown, lefthand similar):
CAUTION:
- If valve tappets and roller rocker arms are to be reused, mark position of rocker arms and valve tappets to ensure they are assembled in original positions.
8. With crankshaft keyway at three o'clock location and RH cylinder head camshaft journal caps and camshafts loose on RH cylinder head, remove rocker arms.
CAUTION:
- If RH tensioner arm and RH timing chain guide are to be reused, mark position of timing chain tensioner arm and timing chain guide to ensure they are assembled in original positions.
9. Remove RH timing chain tensioner arm and RH timing chain.
10. Remove righthand timing chain guide bolts, and RH timing chain guide.
11. Remove righthand timing chain crankshaft sprocket.
12. Rotate crankshaft two revolutions and position crankshaft keyway to the 11 o'clock location. This will position lefthand (LH) cylinder head camshafts to neutral position (base circle).
13. Verify alignment arrows on camshaft are aligned.
14. Remove LH timing chain tensioner bolts and LH timing chain tensioner.
CAUTION:
- Cylinder head camshaft journal caps and cylinder heads are numbered to ensure they are assembled in original positions. If removed, keep camshaft journal caps from each cylinder head together. Do not mix with camshaft journal caps from another cylinder head.
- Remove cylinder head camshaft journal thrust caps first to ensure damage to the thrust caps does not occur.
15. Remove cylinder head camshaft journal thrust cap retaining bolts and caps from LH cylinder head.
Camshaft journal cap bolt removal sequence:
16. Loosen remaining LH cylinder head camshaft journal cap bolts in sequence shown, seven to eight revolutions, to allow camshafts to be raised from cylinder heads. Do not remove bolts completely .
CAUTION:
- If valve tappets and roller rocker arms are to be reused, mark position of rocker arms and valve tappets to ensure they are assembled in original positions.
17. With crankshaft keyway at 11 o'clock location and lefthand cylinder head camshaft journal caps and camshafts loose on lefthand cylinder head, remove rocker arms.
CAUTION:
- If LH timing chain tensioner arm and LH timing chain guide are to be reused, mark position of timing chain tensioner arm and timing chain guide to ensure that they are assembled in their original positions.
18. Remove LH timing chain tensioner arm and LH timing chain.
19. Remove LH timing chain guide retaining bolts, and LH timing chain guide.
20. Remove LH timing chain crankshaft sprocket.
21. Inspect timing chain tensioners, timing chain tensioner arms, timing chain guides, crankshaft sprockets and timing chains for wear or damage. Replace components as necessary.
22. Using small screwdriver, release timing chain tensioner ratchet/pawl mechanism through the access hole in the timing chain tensioner. Compress timing chain tensioner rack and piston into tensioner housing by inserting small wire into top of piston and gently unseat the oil check ball. Compress timing chain tensioners by hand.
NOTE:
- Timing chain tensioners must be reinstalled onto engine while compressed and locked. Failure to compress timing chain tensioner before installing may cause damage to engine.
Fig. 24 Timing chain tensioner compression:
23. With tensioner rack and piston compressed, install a 1.5mm (0.060 inch)drill bit or wire into small hole above the ratchet, engaging lock groove in the rack of the timing chain tensioners.