Chrysler 300/300 Touring/300C, Dodge Magnum. Manual — part 1536

2. To replace spark plug tube seals (2):

a. Using a suitable pry tool, carefully remove tube

seals (2).

b. Position new seal (2) with the part number on

seal facing cylinder head cover.

c. Install seals using MD-998306 (1).

3. Install cylinder head cover (1) and bolts (2). Tighten

to 12 N·m (105 in. lbs.).

4. Position the wiring harness (3) on the cylinder head

cover.

5. Reclip the wire harness track retaining tabs into the

cover.

6. Install the ground strap/resistor retaining bolt onto

the cylinder head cover.

7. Install the ignition coils (2). Tighten mounting

screws to 6.7 N.m (60 in. lbs.)

8. Connect the ignition coil electrical connectors (2).

9. Install upper intake manifold (Refer to 9 - ENGINE/

MANIFOLDS/INTAKE

MANIFOLD

-

INSTALLA-

TION).

10. Connect negative battery cable.

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ENGINE - 3.5L - SERVICE INFORMATION

LX

COVER CYLINDER HEAD - RIGHT

REMOVAL

WARNING: DO NOT START OR RUN ENGINE WITH
CYLINDER HEAD COVER REMOVED FROM THE
ENGINE. DAMAGE OR PERSONAL INJURY MAY
OCCUR.

1. Disconnect the negative battery cable.

2. Remove the upper intake manifold (Refer to 9 -

ENGINE/MANIFOLDS/INTAKE

MANIFOLD

-

REMOVAL).

3. Cover lower intake manifold openings during ser-

vice.

4. Disconnect and remove the three ignition coils (2).

5. Lift up on the wire harness track retaining tabs (4).

6. Remove the ground strap retaining bolt (3) from the

cylinder head cover.

7. Completely loosen the cylinder head cover retain-

ing bolts and remove the cylinder head cover.

INSTALLATION

1. Clean cylinder head and cover mating surfaces.

Inspect and replace gasket (1) and seals (2) as
necessary.

2. To replace spark plug tube seals (2):

a. Using a suitable pry tool, carefully remove tube

seals (2).

b. Position new seal (2) with the part number on

seal facing cylinder head cover.

c. Install seals using MD-99830 (1).

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ENGINE - 3.5L - SERVICE INFORMATION

9 - 2169

3. Install cylinder head cover bolts and tighten to 12

N·m (105 in. lbs.).

4. Install the ground strap retaining bolt (3) to the cyl-

inder head cover.

5. Install the wire harness track (4).

6. Install the ignition coils (2). Tighten mounting

screws to 6.7 N.m (60 in. lbs.).

7. Connect the ignition coil electrical connectors (2).

8. Install upper intake manifold (Refer to 9 - ENGINE/

MANIFOLDS/INTAKE

MANIFOLD

-

INSTALLA-

TION).

9. Connect negative battery cable

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ENGINE - 3.5L - SERVICE INFORMATION

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VALVES & SEATS -INTAKE/EXHAUST

DESCRIPTION

Valves are made of highly heat-resistant steel and are chrome plated to prevent stem scuffing. The intake valve is
a one-piece forging, while the exhaust valve has a forged head with a welded stem for lock groove hardness. The
four valves (two intake and two exhaust) employ a three-groove lock design to help facilitate valve rotation.

OPERATION

The intake valve allows the air/fuel mixture to enter the combustion chamber. The exhaust valve allows the burned
air/fuel mixture to exit the combustion chamber. Also, the intake and exhaust valves seal the combustion chamber
during the compression and power strokes.

STANDARD PROCEDURE

VALVE AND VALVE SEAT REFACING

VALVES

1. Inspect the remaining margin (1) after the valves

are

refaced

(Refer

to

9

-

ENGINE

-

SPECIFICATIONS).

VALVE SEATS

1. When refacing valve seats, it is important that the

correct size valve guide pilot be used for reseating
stones. A true and complete surface must be
obtained.

2. Measure the concentricity of valve seat using dial

indicator. Total runout should not exceed 0.051 mm
(0.002 inch.) total indicator reading.

3. Inspect the valve seat (3) with Prussian blue to

determine where the valve (1) contacts the seat. To
do this, coat valve seat (1) LIGHTLY with Prussian
blue then set valve in place. Rotate the valve with
light pressure. If the blue is transferred to the center of valve face (2), contact is satisfactory. If the blue is trans-
ferred to top edge of valve face (2), then lower valve seat (3) with a 15° stone. If the blue is transferred to the
bottom edge of valve face (2), then raise valve seat (3) with a 65° stone.

NOTE: Valve seats (1) which are worn or burned can be reworked, provided that correct angle and seat
width (1) are maintained. Otherwise cylinder head must be replaced.

4. When seat is properly positioned the width of the intake seats should be 0.75 to 1.25 mm (0.0296 to 0.0493 in.)

and exhaust seats should be 1.25 to 1.75 mm (0.049 to 0.069 in.).

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ENGINE - 3.5L - SERVICE INFORMATION

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