(5) Identify the camshafts before removing from
the head. The camshafts are not interchangeable.
CAMSHAFT END PLAY
(1) Oil camshaft journals and install camshaft
WITHOUTcam follower assemblies. Install rear cam
caps and tighten screws to specified torque.
(2) Using a suitable tool, move camshaft as far
rearward as it will go.
(3) Zero dial indicator (Fig. 33).
(4) Move camshaft as far forward as it will go.
(5) End play travel: 0.05±0.15 mm (0.002±0.010
in.).
(6) If end play is excessive check cylinder head
and camshaft for wear; replace as necessary.
INSTALLATION
CAUTION: Ensure that NONE of the pistons are at
top dead center when installing the camshafts.
(1) Remove camshaft retaining caps and lubricate
bearing journals. Install cam followers and camshafts
with clean oil. Install right and left camshaft bearing
caps #2 thru #5 and right #6. Tighten M6 fasteners
to 12 N´m (105 in. lbs.) in sequence shown in (Fig.
34).
(2) Apply MopartGasket Maker to No. 1 and No.
6 bearing caps (Fig. 35). Install bearing caps and
tighten M8 fasteners to 28 N´m (250 in. lbs.).
(3) Bearing end caps must be installed before
seals can be installed.
(4) Install timing belt, sprockets and covers. Refer
to timing belt service outlined in this section.
(5) Install cylinder head cover using procedure
outlined in this section.Fig. 31 Camshaft Bearing Cap Identification
Fig. 32 Camshaft Bearing CapÐ Removal
Fig. 33 Camshaft End Play
Fig. 34 Camshaft Bearing Cap Tightening Sequence
NS2.4L ENGINE 9 - 29
REMOVAL AND INSTALLATION (Continued)
CAMSHAFT FOLLOWER
REMOVAL
(1) Remove cylinder head cover using procedure
outlined in this section.
(2) Remove timing belt, sprockets and covers
using procedure outlined in this section.
(3) Remove camshaft. Refer to procedure previ-
ously outline this section.
(4) Remove cam follower assemblies from cylinder
head. Keep the cam followers in the order they have
been removed from the head for reassembly.
INSPECTION
Inspect the cam follower assembly for wear or
damage (Fig. 36). Replace as necessary.
INSTALLATION
(1) Lubricate with clean oil and install cam fol-
lower assemblies in their original position on the
hydraulic adjuster and valve stem (Fig. 37).
(2) Install the camshafts. Refer to procedure pre-
viously outlined in this section.
(3) Install timing belt, sprockets and covers using
procedure outlined in this section.
(4) Install cylinder head cover using procedure out-
lined in this section.
BALANCE SHAFTS CARRIER ASSEMBLY
BALANCE SHAFTS
REMOVAL
Refer to Timing Belt Cover, and Timing Belt
removal procedure in this section. To repair balance
shafts carrier assembly.
(1) Remove chain cover, guide and tensioner (Fig.
38). Also see Carrier Assembly Removal for service
procedures requiring only temporary relocation of
assembly.
(2) Remove gear cover retaining stud (double
ended to also retain chain guide). Remove cover and
balance shaft gears (Fig. 38).
Fig. 35 Camshaft Bearing Cap Sealing
Fig. 36 Cam Follower Assembly
Fig. 37 Cam Follower AssembliesÐInstallation
Fig. 38 Chain Cover, Guide and Tensioner
9 - 30 2.4L ENGINENS
REMOVAL AND INSTALLATION (Continued)
NOTE: THE TIMING MARK ON THE SPROCKET,
THE (LOWER) NICKEL PLATED LINK, AND THE
ARROW ON THE SIDE OF THE GEAR COVER
SHOULD LINE UP WHEN THE BALANCE SHAFTS
ARE TIMED CORRECTLY.
(9) If the sprockets are timed correctly install the
balance shaft bolts and tighten to 28 N´m (250 in.
lbs.). A wood block placed between crankcase and
crankshaft counterbalance will prevent crankshaft
and gear rotation.
CHAIN TENSIONING
(1) Install chain tensioner loosely assembled.
(2) Position guide on double ended stud making
sure tab on the guide fits into slot on the gear cover.
Install and tighten nut/washer assembly to 12 N´m
(105 in. lbs.).
(3) Place a shim 1 mm (0.039 in.) thick x 70 mm
(2.75 in.) long or between tensioner and chain. Push
tensioner and shim up against the chain.Apply firm
pressure (5.5 to 6.6 lbs.) directly behind the
adjustment slot to take up all slack.Chain must
have shoe radius contact as shown in (Fig. 46).
(4) With the load applied, tighten top tensioner
bolt first, then bottom pivot bolt. Tighten bolts to 12
N´m (105 in. lbs.). Remove shim.
(5) Install carrier covers and tighten screws to 12
N´m (105 in. lbs.).HYDRAULIC LASH ADJUSTER
REMOVAL
(1) Remove cylinder head cover. Refer to procedure
outlined in this section.
(2) Remove cam follower assembly. Refer to cam-
shaft removal procedure outlined in this section to
gain access to cam followers and lash adjusters.
(3) Mark hydraulic lash adjusters for reassembly
in their original position. Lash adjusters are serviced
as an assembly.
INSTALLATION
(1) Install hydraulic lash adjuster assembly mak-
ing sure adjusters are at least partially full of oil.
This is indicated by little or no plunger travel when
the lash adjuster is depressed.
(2) Install cam follower assembly as previously
outlined in this section.
(3) Install camshaft as previously outlined in this
section.
(4) Install cylinder head cover as previously out-
lined in this section.
VALVE SPRINGS AND VALVE SEALS IN VEHICLE
REMOVAL
(1) Remove camshafts as previously outlined in
this section.
(2) Rotate crankshaft until piston is at TDC on
compression.
(3) With air hose attached to adapter tool
installed in spark plug hole, apply 90-120 psi air
pressure.
(4) Using Special Tool MD-998772-A with adapter
6779 (Fig. 47) compress valve springs and remove
valve locks.
(5) Remove valve spring.
(6) Remove valve stem seal by a using valve stem
seal tool.
INSTALLATION
(1) Install valve seal/valve spring seat assembly
(Fig. 48). Push the assembly down to seat it onto the
valve guide.
(2) Install valve spring and retainer, use Special
Tool MD-998772-A with adapter 6779 to compress
valve springs only enough to install locks (Fig. 47).
Correct alignment of tool is necessary to avoid nick-
ing valve stems.
(3) Remove air hose and install spark plugs.
(4) Install camshafts as previously outlined in this
section.
(5) Install cylinder head cover as previously out-
lined in this section.
Fig. 46 Chain Tension Adjustment
NS2.4L ENGINE 9 - 33
REMOVAL AND INSTALLATION (Continued)
CYLINDER HEAD
REMOVAL
(1) Perform fuel system pressure release proce-
durebefore attempting any repairs.Refer to
Group 14, Fuel System for procedure.
(2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Group 7, Cooling System for pro-
cedure.
(3) Remove air cleaner and disconnect all vacuum
lines, electrical wiring and fuel lines from throttle
body.
(4) Remove throttle linkage. Refer to Group 14,
Fuel System for procedures
(5) Remove accessory drive belts. Refer to Group
7, Cooling System for procedure.
(6) Remove power brake vacuum hose from intake
manifold.
(7) Raise vehicle and remove exhaust pipe from
manifold.(8) Remove power steering pump assembly and
set aside.
(9) Disconnect coil pack wiring connector and
remove coil pack and plug wires from engine.
(10) Remove cam sensor and fuel injectors wiring
connectors.
(11) Remove timing belt and camshaft sprocket.
Refer to procedure outlined in this section.
(12) Remove timing belt idler pulley and rear tim-
ing belt cover.
(13) Remove cylinder head cover using procedure
outlined in this section.
(14) Remove camshafts and cam followers. Refer to
procedures outlined in this section for procedures.
(15) Remove cylinder head bolts and remove cyl-
inder head from engine block.
(16) Inspect and clean cylinder head. Refer to
Cleaning and Inspection outlined in this section for
procedures.
INSTALLATION
NOTE: The Cylinder head bolts should be exam-
ined BEFORE reuse. If the threads are necked
down, the bolts should be replaced (Fig. 49).
Necking can be checked by holding a scale or
straight edge against the threads. If all the threads
do not contact the scale the bolt should be replaced.
(1) Before installing the bolts, the threads should
be coated with engine oil.
(2) Tighten the cylinder head bolts in the
sequence shown in (Fig. 50). Using the 4 step torque
turn method, tighten according to the following val-
ues:
²First All to 34 N´m (25 ft. lbs.)
²Second All to 68 N´m (50 ft. lbs.)
²Third All to 68 N´m (50 ft. lbs.)
CAUTION: Do not use a torque wrench for the fol-
lowing step.
²Fourth Turn an additional 1/4 Turn,
(3) Install camshafts and cam followers. Refer to
procedures outlined in this section for procedures.
Fig. 47 Valve SpringÐRemoval/Installation
Fig. 48 Valve Stem Seal/Valve Spring Seat
Fig. 49 Checking Bolts for Stretching (Necking)
9 - 34 2.4L ENGINENS
REMOVAL AND INSTALLATION (Continued)
(4) Install cylinder head cover using procedure out-
lined in this section.
(5) Install rear timing belt cover and timing belt
idler pulley.
(6) Install timing belt and camshaft sprocket.
Refer to procedure outlined in this section.
(7) Install cam sensor and fuel injectors wiring
connectors.
(8) Install coil pack and plug wires onto the
engine. Connect coil pack wiring connector.
(9) Install power steering pump assembly.
(10) Raise vehicle and install the exhaust pipe to
the manifold.
(11) Install power brake vacuum hose to the intake
manifold.
(12) Install accessory drive belts. Refer to Group 7,
Cooling System for procedure.
(13) Install throttle linkage. Refer to Group 14,
Fuel System for procedures.
(14) Install air cleaner and connect all vacuum
lines, electrical wiring and fuel lines to the throttle
body.
(15) Fill cooling system. Refer to Group 7, Cooling
System for procedure. Connect negative battery
cable.
VALVES AND VALVE SPRINGS
REMOVAL
(1) With cylinder head removed, compress valve
springs using a universal valve spring compressor.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.(3) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves to insure
installation in original location.
(4) Inspect and clean the valves. Refer to Cleaning
and Inspection outlined in this section for procedure.
INSTALLATION
(1) Coat valve stems with clean engine oil and
insert in cylinder head.
(2) Install new valve stem seals on all valves
using a valve stem seal tool (Fig. 51). The valve stem
seals should be pushed firmly and squarely over
valve guide.
CAUTION: When oversize valves are used, the cor-
responding oversize valve seal must also be used.
Excessive guide wear may result if oversize seals
are not used with oversize valves.
(3) Install valve springs and retainers. Compress
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
CAUTION: When depressing the valve spring
retainers with valve spring compressor the locks
can become dislocated. Ensure both locks are in
the correct location after removing tool.
(4) Check the valve spring installed height B after
refacing the valve and seat (Fig. 52). Make sure mea-
surements are taken from top of spring seat to the
bottom surface of spring retainer. If height is greater
than 38.75 mm (1.525 in.), install a .762 mm (0.030
in.) spacer under the valve spring seat to bring
spring height back within specification.
Fig. 50 Cylinder Head Tightening Sequence
Fig. 51 Valve Stem Oil Seal Tool
NS2.4L ENGINE 9 - 35
REMOVAL AND INSTALLATION (Continued)
(6) Lower vehicle and remove upper timing belt
cover fasteners and remove cover.
(7) Remove right engine mount and support
bracket. Refer to Removal and Installation procedure
in this section.
CAUTION: When aligning crankshaft and camshaft
timing marks always rotate engine from crankshaft.
Camshaft should not be rotated after timing belt is
removed. Damage to valve components may occur.
Always align timing marks before removing timing
belt.
(8) Before the removal of the timing belt, rotate
crankshaft until TDC mark on oil pump housing
aligns with TDC mark on crankshaft sprocket (trail-
ing edge of sprocket tooth) (Fig. 58).
NOTE: The crankshaft sprocket mark is located on
the trailing edge of the sprocket tooth. Failure to
align trailing edge of sprocket tooth to mark on oil
pump housing will cause the camshaft marks to be
misaligned (Fig. 58).
(9) Install 6 mm Allen wrench into belt tensioner.
Before rotating the tensioner insert the long end of a
1/8º or 3 mm Allen wrench into the pin hole on thefront of the tensioner (Fig. 59). While rotating the
tensioner counterclockwise push in lightly on the 1/8º
or 3 mm Allen wrench, until it slides into the locking
hole.
(10) Remove timing belt.
Fig. 57 Timing Belt Covers
Fig. 58 Crankshaft and Camshaft Timing
Fig. 59 Locking Timing Belt Tensioner
9 - 38 2.4L ENGINENS
REMOVAL AND INSTALLATION (Continued)
CAUTION: If timing belt was damaged due to incor-
rect tracking (alignment), the belt tensioner assem-
bly must be replace. Refer to Timing Belt Tensioner
Assembly Removal and Installation procedure out-
lined in this section.
INSTALLATION
(1) Set crankshaft sprocket to TDC by aligning
the sprocket with the arrow on the oil pump housing.
(2) Set camshafts timing marks so that the
exhaust camshaft sprocket is a 1/2 notch below the
intake camshaft sprocket (Fig. 61).
CAUTION: Ensure that the arrows on both cam-
shaft sprockets are facing up.
(3) Install timing belt. Starting at the crankshaft,
go around the water pump sprocket, idler pulley,
camshaft sprockets and then around the tensioner
(Fig. 62).
(4) Move the exhaust camshaft sprocket counter-
clockwise (Fig. 62) to align marks and take up belt
slack.
NOTE: A new tensioner is held in the wound posi-
tion by a pull pin.
(5) Remove the pull pin or Allen wrench from the
belt tensioner.
(6) Once timing belt has been installed and ten-
sioner released, rotate crankshaft two (2) complete
revolutions. Verify that the TDC marks on crank-
shaft and timing marks on the camshafts are aligned
as shown in (Fig. 60).
(7) Install right engine mount and support
bracket. Refer to Removal and Installation procedure
in this section.
(8) Install upper timing belt cover bolts 4.5 N´m
(40 in. lbs.).
(9) Install the lower timing belt cover bolts 4.5
N´m (40 in. lbs.).
(10) Install crankshaft damper. Refer to procedure
outlined in this section.
(11) Install accessory drive belts. Refer to Group 7,
Cooling System.
(12) Install right inner splash shield.
(13) Install right front wheel.
Fig. 60 Crankshaft and Camshaft Timing
Fig. 61 Camshaft Sprocket Alignment
NS2.4L ENGINE 9 - 39
REMOVAL AND INSTALLATION (Continued)
CAMSHAFT OIL SEALÐFRONT
REMOVAL
(1) Remove front timing belt covers and timing
belt. Refer to procedures outlined in this section.
(2) Hold camshaft sprocket with Special Tools
C-4687 and 4687-1 while removing center bolt (Fig.
66).
(3) Remove camshaft seal using Special Tool
C-4679-A (Fig. 67).
CAUTION: Do not nick shaft seal surface or seal
bore
INSTALLATION
(1) Shaft seal surface must be free of varnish, dirt
or nicks. Polish with 400 grit paper if necessary.
(2) Install camshaft seal into cylinder head using
Special Tool MD-998306 until flush with head (Fig.
68).
(3) Install camshaft sprocket. While holding
sprocket with Special Tools C-4687 and 4687-1,
tighten center bolt to 101 N´m (75 ft. lbs.) (Fig. 66).
Fig. 65 Timing Belt Tensioner AssemblyÐRemoval/
Installation
Fig. 66 Camshaft SprocketÐRemoval/Installation
Fig. 67 Camshaft Oil SealÐRemoval With C-4679±A
Fig. 68 Camshaft SealÐInstallation
NS2.4L ENGINE 9 - 41
REMOVAL AND INSTALLATION (Continued)