Chrysler Pacifica. Manual - part 679

PISTON RINGS

DESCRIPTION

The piston rings include a moly-filled top ring with

a symmetrical barrel face. The intermediate piston
ring is of the standard chrome design OR Micro-
Napier design. The Micro-Napier design has a
reduced “hook” on the running face, removes the
need for chroming and improves oil economy. The oil
control package consists of two steel rails and an
expander spacer (Fig. 107).

STANDARD PROCEDURE - PISTON RING
FITTING

(1) Wipe cylinder bore clean. Insert ring and push

down with piston to ensure it is square in bore. The
ring gap measurement must be made with the ring
positioning at least 12 mm (0.50 in.) from bottom of
cylinder bore. Check gap with feeler gauge (Fig. 108).
For clearance specifications, (Refer to 9 - ENGINE -
SPECIFICATIONS).

(2) Check piston ring to groove clearance: (Fig.

109). For clearance specifications, (Refer to 9 -
ENGINE - SPECIFICATIONS).

REMOVAL

(1) Remove piston and connecting rod. (Refer to 9 -

ENGINE/ENGINE BLOCK/PISTON & CONNECT-
ING ROD - REMOVAL)

(2) Remove No. 1 and No.2 piston rings from pis-

ton using a ring expander tool (Fig. 112).

(3) Remove upper oil ring side rail.
(4) Remove lower oil ring side rail.
(5) Remove oil ring expander

Fig. 107 PISTON RINGS

1 - TOP PISTON RING
2 - CHROME INTERMEDIATE PISTON RING
3 - MICRO-NAPIER INTERMEDIATE PISTON RING
4 - OIL CONTROL RINGS
5 - SPACER

Fig. 108 CHECK GAP ON PISTON RINGS

1 - FEELER GAUGE

Fig. 109 MEASURING PISTON RING SIDE

CLEARANCE

1 - FEELER GAUGE

ENGINE 3.5L

9 - 71

INSTALLATION

(1) Measure clearance of piston rings to the cylin-

der bore and piston. (Refer to 9 - ENGINE/ENGINE
BLOCK/PISTON

RINGS

STANDARD

PROCE-

DURE)

The No. 1 and No. 2 piston rings have a different

cross section (Fig. 110). Insure that which ever
design No. 2 ring is installed, it is installed with
manufacturers I.D. mark (dot) facing up, towards top
of the piston (Refer to 9 - ENGINE/ENGINE BLOCK/
PISTON RINGS - DESCRIPTION) (Fig. 110).

CAUTION: Install piston rings in the following
order:

• Oil ring expander.

• Upper oil ring side rail.

• Lower oil ring side rail.

• No. 2 Intermediate piston ring.

• No. 1 Upper piston ring.
(2) Install the side rail by placing one end between

the piston ring groove and the expander. Hold end
firmly and press down the portion to be installed
until side rail is in position. Do not use a piston
ring expander during this step (Fig. 111).

(3) Install upper side rail first and then the lower

side rail.

The No. 1 and No. 2 piston rings have a different

(4) Install either No. 2 piston ring and then No. 1

piston ring (Fig. 112).

Fig. 110 PISTON RINGS

1 - TOP PISTON RING
2 - CHROME INTERMEDIATE PISTON RING
3 - MICRO-NAPIER INTERMEDIATE PISTON RING
4 - OIL CONTROL RINGS
5 - SPACER

Fig. 111 SIDE RAIL - INSTALLATION

1 - SIDE RAIL END

Fig. 112 UPPER AND INTERMEDIATE RINGS

9 - 72

ENGINE 3.5L

PISTON RINGS (Continued)

(5) Position piston ring end gaps as shown in (Fig.

113).

(6) Position oil ring expander gap at least 45° from

the side rail gaps but not on the piston pin center or
on the thrust direction. Staggering ring gap is impor-
tant for oil control.

STRUCTURAL COVER

REMOVAL

(1) Raise and support the vehicle.
(2) Remove the bolts attaching the structural collar

to the oil pan and transmission housing (Fig. 114).

(3) Remove the structural collar.

INSTALLATION

CAUTION: The collar must be tightened using this
service procedure, as damage to collar and/or oil
pan may occur.

(1) Install structural collar (Fig. 114) using the fol-

lowing tightening sequence:

• Loosely install the collar to oil pan bolts.

• Loosely install the collar to transmission bolts.

• Initial torque bolts to 27 N·m (20 ft. lbs.).

• Final torque bolts to 55 N·m (40 ft. lbs.).
(2) Lower vehicle.

VIBRATION DAMPER

REMOVAL

(1) Disconnect negative battery cable.
(2) Raise vehicle on hoist.

(3) Remove the right front wheel and accessory

drive belt splash shield.

(4) Remove accessory drive belt (Refer to 7 -

COOLING/ACCESSORY

DRIVE/DRIVE

BELTS

REMOVAL).

(5) Remove vibration damper bolt.
(6) Use

Special

Tool

1023

puller,

and

insert

9020–R, remove crankshaft damper (Fig. 115)

Fig. 113 PISTON RING END GAP POSITION

1 - SIDE RAIL UPPER
2 - NO. 1 RING GAP
3 - PISTON PIN
4 - SIDE RAIL LOWER
5 - NO. 2 RING GAP AND SPACER EXPANDER GAP

Fig. 114 STRUCTURAL COVER

1 - ENGINE OIL PAN
2 - STRUCTURAL SUPPROT
3 - ENGINE MOUNT BRACKET
4 - TRANSMISSION

Fig. 115 Crankshaft Damper—Removal

1 - SPECIAL TOOL 1023 PULLER
2 - SPECIAL TOOL 9020-R INSERT

ENGINE 3.5L

9 - 73

PISTON RINGS (Continued)

INSTALLATION

(1) Install crankshaft damper using Special Tools

C-4685-C1 (5.9 in.) Bolt, with Nut and Thrust Bear-
ing from 6792, and 6792-1 Installer (Fig. 116).

(2) Install vibration damper bolt. Torque bolt to 95

N·m (70 ft. lbs.).

(3) Install accessory drive belt (Refer to 7 - COOL-

ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).

(4) Install the accessory drive belt splash shield

and right front wheel.

(5) Lower vehicle.
(6) Connect negative battery cable.

ENGINE MOUNTING

DESCRIPTION

The engine mounting system are of molded rubber

material and consist of three mounts; right and a left
side support the powertrain, and a front mount con-
trol powertrain torque.

UPPER MOUNT

REMOVAL

(1) Support engine assembly with a floor jack so it

will not rotate.

(2) Remove the air cleaner element housing (Refer

ENGINE/AIR

INTAKE

SYSTEM/AIR

CLEANER HOUSING - REMOVAL).

(3) Remove the upper engine mount bolts from the

inner frame rail (Fig. 117).

(4) Remove the upper engine mount bolts from the

engine (Fig. 117).

Fig. 116 Crankshaft Damper—Installation

1 - SPECIAL TOOL 6792-1
2 - SPECIAL TOOL C-4685-C1

Fig. 117 UPPER ENGINE MOUNT

1 - INTAKE MANIFOLD
2 - UPPER ENGINE MOUNT
3 - FRAME RAIL

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ENGINE 3.5L

VIBRATION DAMPER (Continued)

Content .. 677 678 679 680 ..