Removal

TIMING CHAIN AND CAM SPROCKETS

Fig. 334: TIMING MARK ALIGNMENT

1. - CAMSHAFT TIMING MARKS
2. - CRANKSHAFT TIMING MARKS

1. Disconnect negative battery cable.

2. Drain cooling system.

3. Remove upper intake manifold.

4. Remove cylinder head covers, crankshaft vibration damper, and timing chain cover.

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

5. Align crankshaft sprocket timing mark to mark on oil pump housing (2). The mark on oil pump housing is 60º ATDC of #1 cylinder.

CAUTION: When the timing chain is 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.

Fig. 335: PRIMARY TIMING CHAIN TENSIONER

1. - TENSIONER
2. - RETAINER CAP
3. - BOLT

6. Remove power steering pump and bracket as an assembly. Do not disconnect power steering lines from pump. Reposition pump and support with suitable retaining strap.

7. Remove primary timing chain tensioner retainer cap (2) and tensioner (1) from right cylinder head.

8. Disconnect and remove camshaft position sensor from left cylinder head.

9. Remove timing chain guide access plugs from cylinder heads.

Fig. 336: TIMING DRIVE SYSTEM - PRIMARY

1. - CAMSHAFT DAMPER (IF EQUIPPED)
2. - CHAIN GUIDE
3. - ACCESS PLUG
4. - CAMSHAFT POSITION SENSOR
5. - PRIMARY TIMING CHAIN
6. - CRANKSHAFT SPROCKET
7. - CHAIN GUIDE
8. - CHAIN TENSIONER ARM
9. - CHAIN TENSIONER
10. - CAMSHAFT SPROCKETS
11. - CHAIN GUIDE

NOTE: When camshaft sprocket bolts are removed, the camshafts will rotate in a clockwise direction.

10. Starting with the right camshaft sprocket, remove the sprocket attaching bolts. Remove camshaft damper (if equipped) and sprocket.

11. Remove left side camshaft sprocket attaching bolts and remove sprocket.

12. Remove lower chain guide (7) and tensioner arm (8).

13. Remove the primary timing chain.

14. For removal of crankshaft sprocket.

CRANKSHAFT SPROCKET

Fig. 337: Crankshaft Sprocket - Removal

1. - SPECIAL TOOL 8539
2. - SPECIAL TOOL 5048-6
3. - SPECIAL TOOL 5048-1

1. Remove primary timing chain.

CAUTION: Use care not to turn crankshaft while removing crankshaft sprocket, as damage to valves and or pistons could occur.

2. Remove crankshaft sprocket by first installing the crankshaft damper bolt. Apply grease or equivalent to damper bolt head and position Special Tools 5048-1, 5048-6, and 8539 (1) on sprocket and crankshaft nose. Remove sprocket using care not to rotate the crankshaft.

Installation

TIMING CHAIN AND CAM SPROCKETS

Fig. 338: TIMING CHAIN ALIGNMENT MARKS - PRIMARY

1. Inspect all sprockets (4),(9),(11) and chain guides (2),(5),(10). Replace if worn.

2. For crankshaft sprocket installation procedures.

3. If removed, install the right and left side short chain guides (10). Tighten attaching bolts to 28 N.m (250 in. lbs.).

4. Align the crankshaft sprocket timing mark to the mark on the oil pump housing (3).

NOTE: Lubricate timing chain and guides with engine oil before installation.

5. Place the left side primary chain sprocket onto the chain so that the timing mark is located in between the two (plated) timing links (1).

Fig. 339: TIMING CHAIN ALIGNMENT MARKS - PRIMARY

6. Lower the primary chain with the left side sprocket through the left cylinder head opening.

NOTE: The camshaft sprockets can be allowed to float on the camshaft hub during installation.

7. Loosely position the left side camshaft sprocket over the camshaft hub.

8. Align the timing (plated) link to the crankshaft sprocket timing mark (3).

9. Position the primary chain onto the water pump drive sprocket (11).

10. Align the right camshaft sprocket timing mark to the timing (plated) link on the timing chain (8) and loosely position over the camshaft hub.

11. Verify that all chain timing (plated) links are properly aligned to the timing marks on all sprockets.

12. Install the left side lower chain guide (2) and tensioner arm (5). Tighten attaching bolts to 28 N.m (250 in.lbs.).

NOTE: Inspect the O-ring on the chain guide access plugs before installing.

Replace the O-ring as necessary.

13. Install the chain guide access plugs to the cylinder heads. Tighten plugs to 20 N.m (15 ft. lbs.).

Fig. 340: TIMING CHAIN TENSIONER - OIL PURGING

NOTE: To reset the primary timing chain tensioner, engine oil will first need to be purged from the tensioner.

14. Purge oil from the timing chain tensioner using the following procedure:

1. Place the check ball (2) end of the tensioner into the shallow end of Chain Tensioner Gauge 8186 (3).
2. Using hand pressure, slowly depress the tensioner until oil is purged from the tensioner.

15. Reset the timing chain tensioner using the following procedure:

1. Position the cylinder plunger (4) into the deeper end of Chain Tensioner Gauge 8186 (3).
2. Apply a downward force until tensioner is reset.

NOTE: If oil was not first purged from the tensioner, use slight finger pressure to assist the center arm pin of Chain Tensioner Gauge 8186 to unseat the tensioner's check ball.

CAUTION: Ensure the tensioner is properly reset. The tensioner body (4) must bottom against the top edge of Chain Tensioner Gauge 8186 (3).

Failure to properly perform the resetting procedure may cause tensioner jamming.

NOTE: Inspect the tensioner O-ring (2) for nicks or cuts and make sure the snap ring (1) is correctly installed, replace as necessary.

Fig. 341: PRIMARY TIMING CHAIN TENSIONER

16. Install the reset chain tensioner (1) into the right cylinder head.

17. Position tensioner retaining plate (2) and tighten bolts (3) to 12 N.m (105 in. lbs.).

Fig. 342: TIMING DRIVE SYSTEM - PRIMARY

18. Starting at the right cylinder bank, first position the camshaft damper (1) (if equipped) on the camshaft hub, then insert a 3/8" square drive extension with a breaker bar into the intake camshaft drive hub.

Rotate the camshaft until the camshaft hub aligns to the camshaft sprocket and damper attaching holes.

Install the sprocket attaching bolts and tighten to 28 N.m (250 in. lbs.).

19. Insert a 3/8" square drive extension with a breaker bar into the intake camshaft drive hub and rotate the camshaft until the sprocket attaching bolts can be installed. Tighten the sprocket bolts to 28 N.m (250 in.lbs.).

20. Rotate the crankshaft slightly clockwise to remove timing chain slack, if necessary.

Fig. 343: TIMING CHAIN TENSIONER ACTIVATING

21. Activate the timing chain tensioner by using a flat bladed pry tool to gently pry tensioner arm towards the tensioner slightly. Then release the tensioner arm. Verify the tensioner is activated (extends).

Fig. 344: FRONT PUMP MOUNTING BRACKET BOLTS - 2.7L

22. Install the power steering pump and bracket assembly.

Fig. 345: Accessory Drive Belt System - 2.7L

23. Install the camshaft position sensor and connect the electrical connector.

24. Install the timing chain cover, crankshaft vibration damper, and accessory drive belts.

Fig. 346: Cylinder Head Cover Fasteners

1. - DOUBLE ENDED STUDS
2. - BOLTS

25. Install the cylinder head covers.

26. Install the upper intake manifold and air cleaner housing assembly.

27. Connect the negative battery cable and tighten nut to 5 N.m (45 in. lbs.).

28. Fill the cooling system.

NOTE: After installation of a reset tensioner, engine noise will occur after initial start-up. This noise will normally disappear within 5-10 seconds.

29. Operate the engine until it reaches normal operating temperature. Check cooling system for correct fluid level.

NOTE: The Cam/Crank Variation Relearn procedure must be performed anytime there has been a repair/replacement made to a powertrain system, for example: flywheel, valvetrain, camshaft and/or crankshaft sensors or components.

CRANKSHAFT SPROCKET

Fig. 347: Crankshaft Sprocket - Installation

1. - SPECIAL TOOL 6780-1
2. - SPECIAL TOOL 8179

1. Install crankshaft sprocket using Special Tools 6780-1 and 8179 (2) until sprocket bottoms against crankshaft step flange. Use care not to rotate crankshaft.

Fig. 348: Crankshaft Sprocket Depth Measurement

2. Verify that crankshaft sprocket is installed to proper depth by measuring from sprocket outer face to end of crankshaft. Measurement should read: 39.05 +-0.50 mm (1.5374 +-0.020 in.).

3. Install primary timing chain.