2002 JEEP GRAND CHEROKEE Timing chain

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. 128).
(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.).
CAUTION: Overtightening the tensioner arm torxT
bolt can cause severe damage to the cylinder head.
Tighten torxTbolt to specified torque only.
(3) Install right side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, tighten bolt to 17
N´m (150 in. lbs.).
NOTE: The silver bolts retain the guides to the cyl-
inder 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 torxTbolt to specified torque only.
(5) Install left side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, 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 installa-
tion (Fig. 129).
Fig. 127 Timing Chain System
1 - RIGHT CAMSHAFT SPROCKET AND SECONDARY CHAIN
2 - SECONDARY TIMING CHAIN TENSIONER (LEFT AND RIGHT
SIDE NOT COMMON)
3 - SECONDARY TENSIONER ARM
4 - LEFT CAMSHAFT SPROCKET AND SECONDARY CHAIN
5 - CHAIN GUIDE
6 - TWO PLATED LINKS ON RIGHT CAMSHAFT CHAIN7 - PRIMARY CHAIN
8 - IDLER SPROCKET
9 - CRANKSHAFT SPROCKET
10 - PRIMARY CHAIN TENSIONER
11 - TWO PLATED LINKS ON LEFT CAMSHAFT CHAIN
12 - SECONDARY TENSIONER ARM
9 - 150 ENGINE - 4.7LWJ
TIMING BELT/CHAIN AND SPROCKETS (Continued)

(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. 127).
(9) Lubricate idler shaft and bushings with clean
engine oil.
(10) Install all chains, crankshaft sprocket, and
idler sprocket as an assembly (Fig. 130). After guid-
ing both secondary chains through the block and cyl-
inder 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 cam-
shafts for sprocket installation.
(11) Align left camshaft sprocket ªLº dot to plated
link on chain.
(12) Align right camshaft sprocket ªRº dot to
plated link on chain.
CAUTION: Remove excess oil from the camshaft
sprocket bolt. Failure to do so can result in over-
torque of bolt resulting in bolt failure.
Fig. 128 Resetting Secondary Chain Tensioners
1 - VISE
2 - INSERT LOCK PIN
3 - RATCHET PAWL
4 - RATCHET
5 - PISTON
Fig. 129 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
Fig. 130 Installing Idler Gear, Primary and
Secondary Timing Chains
1 - SPECIAL TOOL 8515
2 - PRIMARY CHAIN IDLER SPROCKET
3 - CRANKSHAFT SPROCKET
WJENGINE - 4.7L 9 - 151
TIMING BELT/CHAIN AND SPROCKETS (Continued)

(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 ªV8º marks on
camshaft sprockets are at the 12 o'clock position (Fig.
127).
CAUTION: Ensure the plate between the left sec-
ondary 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 Adap-
tor Pins 8346, tighten left (Fig. 131) and right (Fig.
132). camshaft sprocket bolts to 122 N´m (90 ft. lbs.).
(19) Rotate engine two full revolutions. Verify tim-
ing marks are at the follow locations:
²primary chain idler sprocket dot is at 12 o'clock
(Fig. 127)
²primary chain crankshaft sprocket dot is at 6
o'clock (Fig. 127)
²secondary chain camshaft sprockets ªV8º marks
are at 12 o'clock (Fig. 127)(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. 133).
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.
Fig. 131 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
9 - 152 ENGINE - 4.7LWJ
TIMING BELT/CHAIN AND SPROCKETS (Continued)

(22) Install timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION) and crankshaft
damper (Refer to 9 - ENGINE/ENGINE BLOCK/VI-
BRATION DAMPER - INSTALLATION).
(23) Install cylinder head covers (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
NOTE: Before installing threaded plug in right cylin-
der head, the plug must be coated with sealant to
prevent leaks.
(24) Coat the large threaded access plug with
MopartThread Sealant with Teflon, then install
into the right cylinder head and tighten to 81 N´m
(60 ft. lbs.) (Fig. 122).
(25) Install the oil fill housing.
(26) Install access plug in left cylinder head (Fig.
122).
(27) Install power steering pump.
(28) Install radiator fan (Refer to 7 - COOLING/
ENGINE/RADIATOR FAN - INSTALLATION).
(29) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(30) Connect negative cable to battery.
Fig. 132 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. 133 Measuring Idler Gear End Play
1 - IDLER SPROCKET ASSEMBLY
2 - DIAL INDICATOR
WJENGINE - 4.7L 9 - 153
TIMING BELT/CHAIN AND SPROCKETS (Continued)