Chrysler 300M, Dodge Interpid. Manual — part 244

CYLINDER HEAD

DESCRIPTION

The aluminum alloy cylinder heads feature cross-

flow type intake and exhaust ports. Valve guides and
seat inserts are powdered metal. Valves are arranged
in a “V”, with each camshaft on center. To improve
combustion speed the chambers are a compact spher-
ical design with a squish area of approximately 30
percent of the piston top area. The cylinder heads are
common to either cylinder bank by reversing the
direction of installation.

DIAGNOSIS AND TESTING—CYLINDER HEAD
GASKET

A cylinder head gasket leak can be located between

adjacent cylinders or between a cylinder and the
adjacent water jacket.

Possible indications of the cylinder head gasket

leaking between adjacent cylinders are:

• Loss of engine power

• Engine misfiring

• Poor fuel economy
Possible indications of the cylinder head gasket

leaking between a cylinder and an adjacent water
jacket are:

• Engine overheating

• Loss of coolant

• Excessive steam (white smoke) emitting from

exhaust

• Coolant foaming

CYLINDER-TO-CYLINDER LEAKAGE TEST

To determine if an engine cylinder head gasket is

leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50–70%
reduction in compression pressure.

CYLINDER-TO-WATER JACKET LEAKAGE TEST

WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.

VISUAL TEST METHOD

With the engine cool, remove the coolant pressure

cap. Start the engine and allow it to warm up until
thermostat opens.

If a large combustion/compression pressure leak

exists, bubbles will be visible in the coolant.

COOLING SYSTEM TESTER METHOD

WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE

PRESSURE

BUILT

UP,

BY

CONTINUOUS

ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).

Install Cooling System Tester 7700 or equivalent to

pressure cap neck. Start the engine and observe the
tester’s pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.

CHEMICAL TEST METHOD

Combustion leaks into the cooling system can also

be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.

REMOVAL

(1) Perform fuel pressure release procedure before

attempting any repairs.. (Refer to 14 - FUEL SYS-
TEM/FUEL

DELIVERY

-

STANDARD

PROCE-

DURE)

(2) Disconnect negative cable from remote battery

jumper terminal.

(3) Drain cooling system. (Refer to 7 - COOLING -

STANDARD PROCEDURE)

(4) Remove crankshaft vibration damper. (Refer to

9

-

ENGINE/ENGINE

BLOCK/VIBRATION

DAMPER - REMOVAL)

(5) Remove front timing belt covers. (Refer to 9 -

ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL)

(6) Remove camshaft sprockets. (Refer to 9 -

ENGINE/VALVE

TIMING/TIMING

BELT/CHAIN

AND SPROCKETS - REMOVAL)

(7) Remove upper and lower intake manifold.

(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL)

(8) Remove V-Band clamp(s) at exhaust manifold

to catalytic converter pipe connection.

NOTE: Do not reuse V-Band Clamp.

(9) Remove rear timing belt cover to cylinder head

fasteners (Fig. 10). Remove the rear covers.

(10) The right side rear timing belt cover has

O-rings to seal the water pump passages to cylinder
block (Fig. 11). Do not reuse O-rings.

(11) Remove cylinder head bolts in REVERSE of

tightening sequence (Fig. 15).

(12) Remove cylinder head(s).

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ENGINE

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CLEANING

To ensure engine gasket sealing, proper surface

preparation must be performed, especially with the
use of aluminum engine components and multi-layer
steel cylinder head gaskets.

NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.

Remove all gasket material from cylinder head and

block (Refer to 9 - ENGINE - STANDARD PROCE-

DURE). Be careful not to gouge or scratch the alumi-
num head sealing surface.

Clean all engine oil passages.

INSPECTION

(1) Before cleaning, check for leaks, damage and

cracks.

(2) Clean cylinder head and oil passages.
(3) Check cylinder head for flatness (Fig. 12).
(4) Cylinder head must be flat within:
• Standard dimension = less than 0.05 mm (0.002

inch.)

• Service Limit = 0.2 mm (0.008 inch.)

• Grinding Limit = Maximum of 0.2 mm (0.008

inch.) is permitted.

CAUTION: 0.20 mm (0.008 in.) MAX is a combined
total dimension of the stock removal limit from cyl-
inder head and block top surface (Deck) together.

INSTALLATION

The cylinder head bolts are tightened using a

torque plus angle procedure. The bolts must be
examined BEFORE reuse. If the threads are
necked down the bolts must be replaced (Fig.
13).

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 must be replaced.

CAUTION: When cleaning cylinder head and cylin-
der block surfaces, DO NOT use a metal scraper
because the surfaces could be cut or ground. Use
ONLY a wooden or plastic scraper.

(1) Clean sealing surfaces of cylinder head and

block.

Fig. 10 Rear Timing Belt Cover Bolts

1 - REAR COVER TO CYLINDER HEAD BOLTS
2 - APPLY SEALANT TO BOLT THREADS
3 - REAR COVER TO CYLINDER BLOCK BOLTS

Fig. 11 Right Side Timing Belt Cover Water Pump

O-Rings

1 - O-RINGS
2 - WATER PUMP IMPELLER

Fig. 12 Checking Cylinder Head Flatness

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ENGINE

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CYLINDER HEAD (Continued)

CAUTION: Ensure that the correct head gaskets are
used and are oriented correctly on cylinder block.
The 3.5L engine head gaskets have perfectly round
combustion sealing rings. The 3.2L engine does
NOT

have

perfectly

round

combustion

sealing

rings.

(2) Install

head

gasket

over

locating

dowels.

Ensure the gasket is installed on the correct side of
engine (Fig. 14).

(3) Install cylinder head over locating dowels.

(4) Before

installing

the

bolts,

lubricate

the

threads with engine oil.

(5) Tighten the cylinder head bolts in the sequence

shown in (Fig. 15). Using the 4 step torque-turn
method, tighten according to the following torque val-
ues:

• Step 1: All to 61 N·m (45 ft. lbs.)

• Step 2: All to 88 N·m (65 ft. lbs.)

• Step 3: All (again) to 88 N·m (65 ft. lbs.)

• Step 4: + 90° Turn Do not use a torque

wrench for this step.

(6) Bolt torque after 90° turn should be over 122

N·m (90 ft. lbs.) in the tightening direction. If not,
replace the bolt.

(7) Clean right rear timing belt cover O-ring seal-

ing surfaces and grooves (Fig. 11). Lubricate new
O-rings with Mopar

t Dielectric Grease or equivalent

to facilitate assembly.

(8) Install rear timing belt covers (Fig. 10) and

(Fig. 11). Tighten bolts to specified torque:

• M10—54 N·m (40 ft. lbs.)

• M8—28 N·m (20 ft. lbs.)

• M6—12 N·m (105 in. lbs.)
(9) Install camshaft sprockets and timing belt.

(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)

(10) Install front timing belt covers. (Refer to 9 -

ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION)

(11) Install crankshaft vibration damper. (Refer to

9

-

ENGINE/ENGINE

BLOCK/VIBRATION

DAMPER - INSTALLATION)

(12) Install upper and lower intake manifold.

(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION)

(13) Connect catalytic converter to exhaust mani-

fold using a new V-band clamp(s). Tighten clamp to
10 N·m (100 in. lbs.).

(14) Fill cooling system. (Refer to 7 - COOLING -

STANDARD PROCEDURE)

(15) Connect negative cable to remote jumper ter-

minal

Fig. 13 Checking Bolts for Stretching (Necking)

1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT

Fig. 14 Cylinder Head Gasket Identification

Fig. 15 Cylinder Head Bolt Tightening Sequence

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ENGINE

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CYLINDER HEAD (Continued)

CAMSHAFT OIL SEAL(S)

REMOVAL

(1) Remove camshaft sprocket(s). (Refer to 9 -

ENGINE/VALVE

TIMING/TIMING

BELT/CHAIN

AND SPROCKETS - REMOVAL)

(2) Use Special Tool C-3981B to remove camshaft

oil seal (Fig. 16).

INSTALLATION

(1) Apply light coat of engine oil to the camshaft

oil seal lip.

(2) Install the oil seal using Special Tool 6788 Seal

Protector Sleeve (Fig. 17) and Seal Installer 6052
(Fig. 18).

(3) Install camshaft sprocket(s). (Refer to 9 -

ENGINE/VALVE

TIMING/TIMING

BELT/CHAIN

AND SPROCKETS - INSTALLATION)

CAMSHAFT(S)

DESCRIPTION

A single overhead camshaft per cylinder head pro-

vides valve actuation. The left camshaft accommo-
dates a cam sensor pick-up wheel and is therefore
longer. Each camshaft is supported by four bearing
journals. Thrust for each camshaft is taken at a
thrust plate attached to the rear of each cylinder
head. Right and left camshaft driving sprockets are
not interchangeable because of the cam sensor
pick-up wheel on the left sprocket. Camshaft bearing
lubrication is provided via oil feed passage through
each rocker shaft pedestal dowel.

OPERATION

The camshaft is driven by the crankshaft via drive

sprockets and belt. The camshaft has precisely
machined lobes to provide accurate valve timing and
duration.

STANDARD PROCEDURE - MEASURING
CAMSHAFT END PLAY

(1) Oil camshaft journals and install camshaft

WITHOUT rocker arms. 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. 19).
(4) Move camshaft as far forward as it will go.
(5) Record reading on dial indicator. For end play

specification, (Refer to 9 - ENGINE - SPECIFICA-
TIONS).

Fig. 16 Camshaft Oil Seal - Removal

1 - SPECIAL TOOL C-3981B

Fig. 17 Camshaft Oil Seal Protector Sleeve

1 - SPECIAL TOOL 6788

Fig. 18 Camshaft Oil Seal - Installation

1 - SPECIAL TOOL 6052

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ENGINE

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