Timing chain cover. Timing chain and sprockets

Timing chain cover

REMOVAL

(1) Disconnect the battery negative cable.

(2) Drain cooling system and remove viscous fan drive assembly. Refer to Group 7, Cooling System for procedures.

(3) Remove radiator shroud. Refer to Group 7, Cooling System for procedure.

(4) Disconnect both heater hoses at timing cover.

(5) Disconnect lower radiator hose at engine.

(6) Remove crankshaft damper. Refer to procedure in this section.

(7) Remove accessory drive belt tensioner assembly (Fig. 73).

(8) Remove the generator and A/C compressor.

(9) Remove cover and gasket (Fig. 74).

INSTALLATION

(1) Clean timing chain cover and block surface.

Inspect cover gasket and replace as necessary.

(2) Install cover and gasket. Tighten fasteners in sequence as shown in (Fig. 74) to 54 N*m (40 ft. lbs.).

Fig. 73 Accessory Drive Belt Tensioner

1 - TENSIONER ASSEMBLY

2 - FASTENER TENSIONER TO FRONT COVER

Fig. 74 Timing Chain Cover Fasteners

(3) Install the A/C compressor and generator.

(4) Install crankshaft damper. Refer to procedure in this section.

(5) Install accessory drive belt tensioner assembly.

Tighten fastener to 54 N*m (40 ft. lbs.).

(6) Install lower radiator hose.

(7) Install both heater hoses.

(8) Install radiator shroud and viscous fan drive assembly. Refer to Group 7, Cooling System for procedure.

(9) Fill cooling system. Refer to Group 7, Cooling System for procedures.

(10) Connect the battery negative cable.

Timing chain and sprockets

REMOVAL

(1) Disconnect negative cable from battery.

(2) Drain cooling system. Refer to Group 7, Cooling System for procedures.

(3) Remove right and left cylinder head covers.

Refer to procedure in this section.

(4) Remove radiator fan shroud. Refer to Group 7, Cooling System for procedure.

(5) Rotate engine until timing mark on crankshaft damper aligns with TDC mark on timing chain cover (Fig. 75) (#1 cylinder exhaust stroke) and the camshaft sprocket "V8" marks are at the 12 o'clock position (Fig. 76).

Fig. 75 Engine Top Dead Center (TDC) Indicator Mark

1 - TIMING CHAIN COVER

2 - CRANKSHAFT TIMING MARKS

(6) Remove power steering pump. Refer to Group 19, Steering for procedures.

(7) Remove access plugs (2) from left and right cylinder heads for access to chain guide fasteners (Fig.

77).

(8) Remove the oil fill housing to gain access to the right side tensioner arm fastener.

(9) Remove crankshaft damper and timing chain cover. Refer to procedures in this section.

Fig. 76 Camshaft Sprocket V8 Marks

1 - LEFT CYLINDER HEAD

2 - RIGHT CYLINDER HEAD

Fig. 77 Cylinder Head Access Plug Location

1 - RIGHT CYLINDER HEAD ACCESS PLUG

2 - LEFT CYLINDER HEAD ACCESS PLUG

(10) Collapse and pin primary chain tensioner (Fig. 78).

CAUTION: Plate behind left secondary chain tensioner could fall into oil pan. Therefore, cover pan opening.

(11) Remove secondary chain tensioners.

(12) Remove camshaft position sensor from right cylinder head (Fig. 79).

Fig. 78 Collapsing And Pinning Primary Chain Tensioner

1 - PRIMARY CHAIN TENSIONER

2 - ADJUSTABLE PLIERS

3 - SPECIAL TOOL 8514

Fig. 79 Camshaft Position Sensor-Removal

1 - CRANKSHAFT POSITION SENSOR

2 - CYLINDER HEAD COVER

3 - CAMSHAFT POSITION SENSOR

4 - RIGHT SIDE CYLINDER BLOCK

CAUTION: Care should be taken not to damage camshaft target wheel. Do not hold target wheel while loosening or tightening camshaft sprocket.

Do not place the target wheel near a magnetic source of any kind. A damaged or magnetized target wheel could cause a vehicle no start condition. CAUTION: Do not forcefully rotate the camshafts or crankshaft independently of each other. Damaging intake valve to piston contact will occur. Ensure negative battery cable is disconnected to guard against accidental starter engagement.

(13) Remove left and right camshaft sprocket bolts.

(14) While holding the left camshaft steel tube with adjustable pliers, (Fig. 80) remove the left camshaft sprocket. Slowly rotate the camshaft approximately 15 degrees clockwise to a neutral position.

(15) While holding the right camshaft steel tube with adjustable pliers, (Fig. 81) remove the right camshaft sprocket. Slowly rotate the camshaft approximately 45 degrees counterclockwise to a neutral position.

(16) Remove idler sprocket assembly bolt.

(17) Slide the idler sprocket assembly and crank sprocket forward simultaneously to remove the primary and secondary chains.

(18) Remove both pivoting tensioner arms and chain guides.

Fig. 80 Camshaft Rotation-Left Side

1 - CAMSHAFT SPROCKET AND CHAIN

2 - ADJUSTABLE PLIERS

3 - CAMSHAFT

Fig. 81 Camshaft Rotation-Right Side

1 - ADJUSTABLE PLIERS

2 - CAMSHAFT DOWEL

(19) Remove chain tensioner

Fig. 82 Timing Chain System

1 - RIGHT CAMSHAFT SPROCKET AND SECONDARY CHAIN

2 - SECONDARY TIMING CHAIN TENSIONER

3 - SECONDARY TENSIONER ARM

4 - LEFT CAMSHAFT SPROCKET AND SECONDARY CHAIN

5 - CHAIN GUIDE

6 - TWO PLATED LINKS ON RIGHT CAMSHAFT CHAIN

7 - PRIMARY CHAIN

8 - IDLER SPROCKET

9 - CRANKSHAFT SPROCKET

10 - PRIMARY CHAIN TENSIONER

11 - TWO PLATED LINKS ON LEFT CAMSHAFT CHAIN

12 - SECONDARY TENSIONER ARM

INSPECTION OF COMPONENTS

Inspect the following components:

• Sprockets for excessive tooth wear. Some tooth markings are normal and not a cause for sprocket replacement.
• Idler sprocket assembly bushing and shaft for excessive wear.
• Idler sprocket assembly spline joint. The joint should be tight with no backlash or axial movement.
• Chain guides and tensioner arms. Replace these parts if grooving in plastic face is more than 1 mm (0.039 in.) deep. If plastic face is severely grooved or melted, the tensioner lube jet may be clogged. The tensioner should be replaced.
• secondary chain tensioner piston and ratcheting device. Inspect for evidence of heavy contact between tensioner piston and tensioner arm. If this condition exist the tensioner tensioner arm and chain should be replaced.
• Primary chain tensioner plastic faces. Replace as required.

INSTALLATION

(1) Using a vise, lightly compress the secondary chain tensioner piston until the piston step is flush with the tensioner body. Using a pin or suitable tool, release ratchet pawl by pulling pawl back against spring force through access hole on side of tensioner.

While continuing to hold pawl back, Push ratchet device to approximately 2 mm from the tensioner body. Install Special Tool 8514 lock pin into hole on front of tensioner. Slowly open vise to transfer piston spring force to lock pin (Fig. 83).

(2) Position primary chain tensioner over oil pump and insert bolts into lower two holes on tensioner bracket. Tighten bolts to 28 N*m (250 in. lbs.).

Fig. 83 Resetting Secondary Chain Tensioners

1 - VISE

2 - INSERT LOCK PIN

3 - RATCHET PAWL

4 - RATCHET

5 - PISTON

CAUTION: Overtightening the tensioner arm torxT bolt can cause severe damage to the cylinder head.

Tighten torxT bolt to specified torque only.

(3) Install right side chain tensioner arm. Apply Mopart Lock N, Seal to torxt bolt, tighten bolt to 17 N*m (150 in. lbs.).

NOTE: The silver bolts retain the guides to the cylinder heads and the black bolts retain the guides to the engine block.

(4) Install the left side chain guide. Tighten the bolts to 28 N*m (250 in. lbs.).

CAUTION: Overtightening the tensioner arm torxT bolt can cause severe damage to the cylinder head.

Tighten torxT bolt to specified torque only.

(5) Install left side chain tensioner arm. Apply Mopart Lock N, Seal to torxt bolt, tighten bolt to 17 N*m (150 in. lbs.).

(6) Install the right side chain guide. Tighten the bolts to 28 N*m (250 in. lbs.).

(7) Install both secondary chains onto the idler sprocket. Align two plated links on the secondary chains to be visible through the two lower openings on the idler sprocket (4 o'clock and 8 o'clock). Once the secondary timing chains are installed, position special tool 8515 to hold chains in place for installation (Fig. 84).

(8) Align primary chain double plated links with the timing mark at 12 o'clock on the idler sprocket.

Align the primary chain single plated link with the timing mark at 6 o'clock on the crankshaft sprocket (Fig. 82).

Fig. 84 Installing Secondary Timing Chains on Idler Sprocket

1 - LOCK ARM

2 - RIGHT CAMSHAFT CHAIN

3 - SECONDARY CHAINS RETAINING PINS (4)

4 - IDLER SPROCKET

5 - LEFT CAMSHAFT CHAIN

6 - SPECIAL TOOL 8515

(9) Lubricate idler shaft and bushings with clean engine oil.

(10) Install all chains, crankshaft sprocket, and idler sprocket as an assembly (Fig. 85). After guiding both secondary chains through the block and cylinder head openings, affix chains with a elastic strap or the equivalent, This will maintain tension on chains to aid in installation.

NOTE: It will be necessary to slightly rotate camshafts for sprocket installation.

(11) Align left camshaft sprocket "L" dot to plated link on chain.

(12) Align right camshaft sprocket "R" dot to plated link on chain.

CAUTION: Remove excess oil from the camshaft sprocket bolt. Failure to do so can result in overtorque of bolt resulting in bolt failure.

Fig. 85 Installing Idler Gear, Primary and Secondary Timing Chains

1 - SPECIAL TOOL 8515

2 - PRIMARY CHAIN IDLER SPROCKET

3 - CRANKSHAFT SPROCKET

(13) Remove Special Tool 8515, then attach both sprockets to camshafts. Remove excess oil from bolts, then Install sprocket bolts, but do not tighten at this time.

(14) Verify that all plated links are aligned with the marks on all sprockets and the "V8" marks on camshaft sprockets are at the 12 o'clock position (Fig.

82).

CAUTION: Ensure the plate between the left secondary chain tensioner and block is correctly installed.

(15) Install both secondary chain tensioners.

Tighten bolts to 28 N*m (250 in. lbs.).

NOTE: Left and right secondary chain tensioners are not common.

(16) Before installing idler sprocket bolt, lubricate washer with oil, and tighten idler sprocket assembly retaining bolt to 34 N*m (25 ft. lbs.).

(17) Remove all locking pins (3) from tensioners.

CAUTION: After pulling locking pins out of each tensioner, DO NOT manually extend the tensioner(s) ratchet. Doing so will over tension the chains, resulting in noise and/or high timing chain loads.

(18) Using Special Tool 6958, Spanner with Adaptor Pins 8346, tighten left (Fig. 86) and right (Fig.

87). camshaft sprocket bolts to 122 N*m (90 ft. lbs.).

Fig. 86 Tightening Left Side Camshaft Sprocket Bolt

1 - TORQUE WRENCH

2 - CAMSHAFT SPROCKET

3 - LEFT CYLINDER HEAD

4 - SPECIAL TOOL 6958 SPANNER WITH ADAPTER PINS 8346

(19) Rotate engine two full revolutions. Verify timing marks are at the follow locations:

• primary chain idler sprocket dot is at 12 o'clock (Fig. 82)
• primary chain crankshaft sprocket dot is at 6 o'clock (Fig. 82)
• secondary chain camshaft sprockets "V8" marks are at 12 o'clock (Fig. 82)

(20) Lubricate all three chains with engine oil.

(21) After installing all chains, it is recommended that the idler gear end play be checked (Fig. 88). The end play must be within 0.10-0.25 mm (0.004-0.010 in.). If not within specification, the idler gear must be replaced.

(22) Install timing chain cover and crankshaft damper. Refer to procedures in this section.

(23) Install cylinder head covers. Refer to procedures in this section.

NOTE: Before installing threaded plug in right cylinder head, the plug must be coated with sealant to prevent leaks.

Fig. 87 Tightening Right Side Camshaft Sprocket Bolt

1 - TORQUE WRENCH

2 - SPECIAL TOOL 6958 WITH ADAPTER PINS 8346

3 - LEFT CAMSHAFT SPROCKET

4 - RIGHT CAMSHAFT SPROCKET

Fig. 88 Measuring Idler Gear End Play

1 - IDLER SPROCKET ASSEMBLY

2 - DIAL INDICATOR

(24) Coat the large threaded access plug with Mopart Thread Sealant with Teflon, then install into the right cylinder head and tighten to 81 N*m (60 ft. lbs.) (Fig. 77).

(25) Install the oil fill housing.

(26) Install access plug in left cylinder head (Fig.77).

(27) Install power steering pump. Refer to Group 19, Steering for procedure.

(28) Install radiator fan shroud. Refer to Group 7, Cooling System for procedure.

(29) Fill cooling system. Refer to Group 7, Cooling System for coolant fill procedure.

(30) Connect negative cable to battery.