Removal

1. CAUTION: At no time, when the timing chain(s) are removed and the cylinder heads (6049) are installed, may the crankshaft (6303) and/or camshafts (6250) be rotated without following established procedures. Failure to follow these directions will result in valve and/or piston damage.

NOTE: Because this is not a free-wheeling engine, if it has "jumped time," there will be damage to the valves and/or pistons (6108) and will require the removal of the cylinder heads.

Remove engine front cover (6019).
2. Remove rocker arms (6564).
3. Remove crankshaft position sensor pulse wheel.

Fig. 17 Setting Engine To TDC Of No. 1 Cylinder:

4. NOTE: Timing marks on the camshaft sprocket (6256) must be on the top of both sprockets as shown.

Rotate engine to No.1 top dead center (TDC).

Fig. 18 Camshaft Positioning Tool Installation:

5. NOTE: To prevent accidental rotation of the camshafts and possible engine damage, install Camshaft Positioning Tool T93P-6256-A and Camshaft Holding Tool T93P-6256-AH. Install Camshaft Positioning Tool T93P-6256-A in rear D-slots of camshafts as shown.

6. CAUTION: Failure to use Camshaft Holding Tool T93P-6256-AH while assembling or disassembling timing chains will result in damage to D-slots or Camshaft Positioning Tool T93P-6256-A.

Fig. 24 Camshaft Holding Tool:

Install Camshaft Holding Tool T93P-6256-AH onto camshafts as shown to keep camshafts from rotating and to prevent deformation of Camshaft Positioning Tool T93P-6256-A.
7. Remove two bolts retaining RH primary timing chain tensioner (6L266) to cylinder head and remove primary timing chain tensioner.

RH Timing Chain Tensioner:

8. Remove bolt retaining RH timing chain tensioner arm (6L253) and remove timing chain tensioner arm.

9. NOTE: Two bolts retaining the timing chain guide (6K297) to the cylinder head are longer than the one to the cylinder block (6010).

Remove three bolts retaining RH timing chain guide and remove timing chain guide.

10. NOTE: Do not loosen the camshaft sprocket bolts.

Remove RH primary timing chain from camshaft sprocket (6256) and crankshaft sprocket (6306).
11. Remove RH crankshaft sprocket (6306) and RH primary timing chain.

12. CAUTION: Failure to use Camshaft Holding Tool T93P-6256-AH while removing or tightening camshaft bolts may result in damage to camshaft D-slots or Camshaft Positioning Tool T93P-6256-A.

If it is necessary to remove primary or secondary camshaft sprockets or secondary timing chain tensioners, install camshaft torquing tool at center area of camshafts.

13. NOTE: Camshaft Positioning Tool T93P-6256-A must be installed on camshafts to prevent camshafts from rotating.

Remove camshaft sprocket retaining bolts.

14. CAUTION: Secondary timing chain tensioner plunger is spring-loaded. Care must be taken to prevent plunger from dropping out of timing chain tensioner during disassembly.

Compress secondary timing chain tensioners and lock the timing chain tensioner in the compressed position using clip. Remove secondary timing chain and camshaft sprockets.
15. Remove secondary timing chain tensioner.

16. CAUTION: Failure to use camshaft torquing tool while removing or tightening camshaft bolts may result in damage to camshaft D-slots or Camshaft Positioning Tool T93P-6256-A.

Remove two bolts retaining LH primary timing chain tensioner to cylinder head and remove primary timing chain tensioners.
17. Remove bolt retaining LH timing chain tensioner arm and remove LH timing chain tensioner arm.
18. Remove three bolts retaining LH timing chain guide and remove timing chain guide.
19. Remove LH primary timing chain from camshaft sprocket and crankshaft sprocket.
20. If necessary, remove primary or secondary camshaft sprockets or secondary timing chain tensioners with Camshaft Holding Tool T93P-6256-AH at center area of camshafts.
21. Remove camshaft sprocket retaining bolts.

22. CAUTION: Secondary timing chain tensioner plunger is spring-loaded. Care must be taken to prevent plunger from dropping out of timing chain tensioner during disassembly.

Compress secondary chain tensioner and lock the chain tensioner in the compressed position using clip. Remove secondary timing chain and camshaft sprockets.

23. CAUTION: Do not rotate crankshaft and/or camshafts or engine damage may occur.

NOTE: Camshaft Holding Tool T93P-6256-AH and Camshaft Positioning Tool T93P-6256-A or equivalent must be installed on camshafts to prevent camshafts from rotating.

Inspect friction material on timing chain tensioner arms and timing chain guides. If worn or damaged remove and clean oil pan (6675) and replace oil pump screen cover and tube (6622).