CONDITION POSSIBLE CAUSES CORRECTION
OIL CONSUMPTION OR SPARK
PLUGS FOULED1. PCV system malfunction. 1. Check system and repair as
necessary. (Refer to 25 -
EMISSIONS CONTROL/
EVAPORATIVE EMISSIONS/PCV
VALVE - DIAGNOSIS AND
TESTING)
2. Worn, scuffed or broken rings. 2. Hone cylinder bores. Install new
rings.
3. Carbon in oil ring slots. 3. Install new rings.
4. Rings fitted too tightly in grooves. 4. Remove rings and check
grooves. If groove is not proper
width, replace piston.
5. Worn valve guide(s). 5. Replace cylinder head assembly.
6. Valve stem seal(s) worn or
damaged.6. Replace seal(s).
STANDARD PROCEDURE - ENGINE CORE AND
OIL GALLERY PLUGS
Using a blunt tool such as a drift and a hammer,
strike the bottom edge of the cup plug. With the cup
plug rotated, grasp firmly with pliers or other suit-
able tool and remove plug (Fig. 2).
CAUTION: Do not drive cup plug into the casting as
restricted cooling can result and cause serious
engine problems.
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.Lightly coat inside of cup plug hole with Mopart
Stud and Bearing Mount. Make certain the new plug
is cleaned of all oil or grease. Using proper drive
plug, drive plug into hole so that the sharp edge of
the plug is at least 0.5 mm (0.020 in.) inside the
lead-in chamfer.
It is not necessary to wait for curing of the sealant.
The cooling system can be refilled and the vehicle
placed in service immediately.
STANDARD PROCEDURE - REPAIR OF
DAMAGED OR WORN THREADS
Damaged or worn threads (excluding spark plug
and camshaft bearing cap attaching threads) can be
repaired. Essentially, this repair consists of drilling
out worn or damaged threads, tapping the hole with
a special Heli-Coil Tap, (or equivalent) and installing
an insert into the tapped hole. This brings the hole
back to its original thread size.
CAUTION: Be sure that the tapped holes maintain
the original center line.
Heli-Coil tools and inserts are readily available
from automotive parts jobbers.
STANDARD PROCEDURE - HYDROSTATIC
LOCKED ENGINE
When an engine is suspected to be hydrostatically
locked, regardless of what caused the problem, the
following steps should be used.
CAUTION: DO NOT use starter motor to rotate the
engine, severe damage may occur.
Fig. 2 CORE HOLE PLUG REMOVAL
1 - CYLINDER BLOCK
2 - REMOVE PLUG WITH PLIERS
3 - STRIKE HERE WITH HAMMER
4 - DRIFT PUNCH
5 - CUP PLUG
RSENGINE 2.4L9-9
ENGINE 2.4L (Continued)
age to the valve guides.Identify valves to insure
installation in original location.
(4) Inspect the valves. (Refer to 9 - ENGINE/CYL-
INDER HEAD/VALVE SPRINGS - INSPECTION)
INSPECTION
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
should be tested for correct tension. Discard the
springs that do not meet specifications. The following
specifications apply to both intake and exhaust
valves springs:
²Valve Closed Nominal TensionÐ76 lbs. @ 38.0
mm (1.50 in.)
²Valve Open Nominal TensionÐ136 lbs. @ 29.75
mm (1.17 in.)
(2) Inspect each valve spring for squareness with a
steel square and surface plate, test springs from both
ends. If the spring is more than 1.5 mm (1/16 inch)
out of square, install a new spring.
INSTALLATION - CYLINDER HEAD ON
(1) Install valve seal/valve spring seat assembly
(Fig. 35). 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. 34).
Correct alignment of tool is necessary to avoid nick-
ing valve stems.
(3) Remove air hose and install spark plugs.
(4) Install camshafts and cylinder head cover .
INSTALLATION - CYLINDER HEAD OFF
(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. 36). 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.
Fig. 34 Valve Spring - Removal/Installation
1 - VALVE SPRING COMPRESSOR MD 998772A
2 - AIR HOSEFig. 35 Valve Stem Seal/Valve Spring Seat
1 - VALVE RETAINING LOCKS
2 - VALVE SPRING
3 - VALVE SEAL AND VALVE SPRING SEAT ASSEMBLY
4 - VALVE SPRING RETAINER
Fig. 36 Valve Stem Oil Seal Tool
1 - VALVE SEAL TOOL
2 - VALVE STEM
RSENGINE 2.4L9-31
VALVE SPRINGS (Continued)
ROCKER ARMS
REMOVAL
NOTE: This procedure is for in-vehicle service with
camshafts installed.
(1) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(2) Remove fuel rail. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL RAIL - REMOVAL)
(3) Remove spark plugs.
(4) Rotate engine until the camshaft lobe, on the
follower being removed, is position on its base circle
(heel). Also, the piston should be a minimum of 6.3
mm (0.25 in) below TDC position.
CAUTION: If cam follower assemblies are to be
reused, always mark position for reassembly in
their original positions.
(5) Using Special Tools 8215 and 8436 slowly
depress valve assembly until rocker arm can be
removed (Fig. 39).
NOTE: It may be necessary to remove additional
brackets or components to allow clearance for tool
handle movement.
(6) Repeat removal procedure for each rocker arm.
INSPECTION
Inspect the rocker arm for wear or damage (Fig.
40). Replace as necessary.
INSTALLATION
(1) Lubricate rocker arm with clean engine oil.
(2) Using Special Tools 8215 and 8436 slowly
depress valve assembly until rocker arm can be
installed on the hydraulic lifter and valve stem (Fig.
39).
(3) Repeat installation procedure for each rocker
arm.
(4) Install spark plugs.
(5) Install fuel rail. (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL RAIL - INSTALLATION)
(6) Install cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
ENGINE BLOCK
DESCRIPTION
The cast iron cylinder block is a two-piece assem-
bly, consisting of the cylinder block and bedplate (Fig.
41). The bedplate incorporates the main bearing caps
and bolts to the cylinder block. This design offers a
much stronger lower end and increased cylinder
block rigidity. The rear oil seal retainer is integral
with the block. The bedplate and block are serviced
as an assembly.
STANDARD PROCEDURE - PISTON TO
CYLINDER BORE FITTING
Piston and cylinder wall must be clean and dry.
Piston diameter should be measured 90 degrees to
piston pin about 14 mm (9/16 inch.) from the bottom
of the skirt as shown in (Fig. 43). Cylinder bores
Fig. 39 Rocker Arm - Removal/Installation
1 - SPECIAL TOOL 8215
2 - ROCKER ARM
3 - SPECIAL TOOL 8436
Fig. 40 Rocker Arm
1 - TIP
2 - LASH ADJUSTER POCKET
3 - ROLLER
RSENGINE 2.4L9-33
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE STALLS
OR IDLES
ROUGH1. Idle speed too low. 1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)
2. Incorrect fuel mixture. 2. (Refer to Appropriate Diagnostic
Information)
3. Intake manifold leakage. 3. Inspect intake manifold, manifold gasket,
and vacuum hoses.
4. Faulty ignition coil(s). 4. Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
ENGINE LOSS OF
POWER1. Dirty or incorrectly gapped plugs. 1. Clean plugs and set gap.
2. Contamination in fuel system. 2. Clean system and replace fuel filter.
3. Faulty fuel pump. 3. Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
4. Incorrect valve timing. 4. Correct valve timing.
5. Leaking cylinder head gasket. 5. Replace cylinder head gasket.
6. Low compression. 6. Test compression of each cylinder.
7. Burned, warped, or pitted valves. 7. Replace valves.
8. Plugged or restricted exhaust system. 8. Perform exhaust restriction test. (Refer to
11 - EXHAUST SYSTEM - DIAGNOSIS AND
TESTING) Install new parts, as necessary.
9. Faulty ignition coil(s). 9. Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
ENGINE MISSES
ON
ACCELERATION1. Dirty or incorrectly gapped spark plugs. 1. Clean spark plugs and set gap.
2. Contamination in Fuel System. 2. Clean fuel system and replace fuel filter.
3. Burned, warped, or pitted valves. 3. Replace valves.
4. Faulty ignition coil(s). 4. Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
ENGINE MISSES
AT HIGH SPEED1. Dirty or incorrect spark plug gap. 1. Clean spark plugs and set gap.
2. Faulty ignition coil(s). 2. Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
3. Dirty fuel injector(s). Test and replace as necessary. (Refer to
Appropriate Diagnostic Information)
4. Contamination in fuel system. 4. Clean system and replace fuel filter.
RSENGINE 3.3/3.8L9-75
ENGINE 3.3/3.8L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
OIL PRESSURE
DROP1. Low oil level. 1. Check engine oil level.
2. Faulty oil pressure sending unit. 2. Install new sending unit.
3. Low oil pressure. 3. Check sending unit and main bearing oil
clearance.
4. Clogged oil filter. 4. Install new oil filter.
5. Worn parts in oil pump. 5. Replace worn parts or pump.
6. Thin or diluted oil. 6. Change oil to correct viscosity.
7. Oil pump relief valve stuck. 7. Remove valve and inspect, clean, or
replace.
8. Oil pump suction tube loose. 8. Remove oil pan and install new tube or
clean, if necessary.
9. Oil pump cover warped or cracked. 9. Install new oil pump.
10. Excessive bearing clearance. 10. Measure bearings for correct clearance.
OIL LEAKS 1. Misaligned or deteriorated gaskets. 1. Replace gasket(s).
2. Loose fastener, broken or porous metal
part.2. Tighten, repair or replace the part.
3. Misaligned or deteriorated cup or
threaded plug.3. Replace as necessary.
OIL
CONSUMPTION
OR SPARK
PLUGS FOULED1. PCV system malfunction. 1. Check system and repair as necessary.
(Refer to 25 - EMISSIONS CONTROL/
EVAPORATIVE EMISSIONS/PCV VALVE -
DIAGNOSIS AND TESTING)
2. Worn, scuffed or broken rings. 2. Hone cylinder bores. Install new rings.
3. Carbon in oil ring slots. 3. Install new rings.
4. Rings fitted too tightly in grooves. 4. Remove rings and check grooves. If
groove is not proper width, replace piston.
5. Worn valve guide(s). 5. Replace cylinder head assembly.
6. Valve stem seal(s) worn or damaged. 6. Replace seal(s).
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair as necessary.(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.
(5)If the oil leak source is not positively
identified at this time, proceed with the air leak
detection test method as follows:
²Disconnect the fresh air hose (make-up air) at
the cylinder head cover and plug or cap the nipple on
the cover.
²Remove the PCV valve hose from the cylinder
head cover. Cap or plug the PCV valve nipple on the
cover.
²Attach an air hose with pressure gauge and reg-
ulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
RSENGINE 3.3/3.8L9-77
ENGINE 3.3/3.8L (Continued)
²Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provides the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
²If the leakage occurs at the crankshaft rear oil
seal area, refer to the section, Inspection for Rear
Seal Area Leak.
(6) If no leaks are detected, turn off the air supply.
Remove the air hose, all plugs, and caps. Install the
PCV valve and fresh air hose (make-up air). Proceed
to next step.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
NOTE: If oil leakage is observed at the dipstick tube
to block location; remove the tube, clean and reseal
using MoparTStud & Bearing Mount (press fit tube
applications only), and for O-ring style tubes,
remove tube and replace the O-ring seal.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak. If a leak is
present in this area, remove transmission for further
inspection.
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, oil gallery cup
plug, bedplate to cylinder block mating surfaces
and seal bore. See proper repair procedures for
these items.
(4) If no leaks are detected, pressurize the crank-
case as previously described.
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible thecrankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
(7) After the oil leak root cause and appropriate
corrective action have been identified, replace compo-
nent(s) as necessary.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal
operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.
(3) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.
(4) Disconnect the ignition coil electrical connector.
(5) Be sure throttle blade is fully open during the
compression check.
(6) Insert compression gage adaptor Special Tool
8116 or the equivalent, into the #1 spark plug hole in
cylinder head. Connect the 0±500 psi (Blue) pressure
transducer with cable adaptors to the DRBIIIt.
(7) Crank engine until maximum pressure is
reached on gage. Record this pressure as #1 cylinder
pressure.
(8) Repeat the previous step for all remaining cyl-
inders.
(9) Compression should not be less than 689 kPa
(100 psi) and not vary more than 25 percent from cyl-
inder to cylinder.
(10) If one or more cylinders have abnormally low
compression pressures, repeat the compression test.
(11) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
9 - 78 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
(2) Inspect seal on the cover bolt for wear or dam-
age (Fig. 24). Replace bolt assembly as necessary.
NOTE: The cylinder head cover bolts contain a
torque limiter sleeve and a seal (Fig. 24). The seal
and torque sleeve is replaced with the bolt.
(3) Assemble gasket to cylinder cover by inserting
the bolt assemblies through each bolt hole on the
cover and gasket (Fig. 24).
(4) Install cylinder head cover and bolts (Fig. 25).
(5) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 25).
(6) Connect PCV hose to cylinder head cover.
(7) Connect power steering pump supply hose sup-
port clip to cylinder head cover (Fig. 22).
(8) Connect spark plug wires to spark plugs.
(9) Install wiper module. (Refer to 8 - ELECTRI-
CAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION)
(10) Connect negative cable to battery.
CYLINDER HEAD COVER -
LEFT
REMOVAL
(1) Disconnect spark plug wires from spark plugs.
(2) Disconnect crankcase vent hose from cylinder
head cover.
(3) Remove cylinder head cover bolts.
(4) Remove cylinder head cover and gasket.
Fig. 23 PCV Hose
1 - HOSE - PCV
2 - P C V VA LV E
Fig. 24 CYLINDER HEAD COVER GASKET
1 - CYLINDER HEAD COVER
2 - BOLT
3 - SEAL (SERVICED WITH BOLT)
4 - GASKET
Fig. 25 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
9 - 98 ENGINE 3.3/3.8LRS
CYLINDER HEAD COVER - RIGHT (Continued)
INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
(2) Assemble gasket to cylinder cover by inserting
the fasteners through each bolt hole on cover and
gasket (Fig. 24).
(3) Install the cylinder head cover and bolts (Fig.
25).
(4) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 25).
(5) Connect crankcase vent hose.
(6) Connect spark plug wires to spark plugs.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves have chrome plated valve stems with
four-bead lock grooves. The valve stem seals are
made of Viton rubber.
OPERATION
The two valves per cylinder are opened using
hydraulic lifters, push rods, and rocker arms.
STANDARD PROCEDURE - REFACING VALVES
AND VALVE SEATS
The intake and exhaust valves and seats are
machined to specific angles (Fig. 26).
VALVES
(1) Inspect the remaining margin after the valves
are refaced (Fig. 27). (Refer to 9 - ENGINE - SPEC-
IFICATIONS)
VALVE SEATS
CAUTION: Remove metal from valve seat only. Do
not remove material from cylinder head (Fig. 28).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
Fig. 26 Valve Face and Seat
1 - SEAT WIDTH
2 - FACE ANGLE
3 - SEAT ANGLE
4 - SEAT CONTACT AREA
Fig. 27 Valve Margin
1 - VALVE FACE
2 - VALVE MARGIN
Fig. 28 Refacing Valve Seats
1 - REFACING STONE MUST NOT CUT INTO CYLINDER HEAD
2-STONE
3 - PILOT
4 - SEAT
RSENGINE 3.3/3.8L9-99
CYLINDER HEAD COVER - LEFT (Continued)