Dodge Ram Truck 1500-2500-3500. Manual — part 1298

INSTALLATION

1. Before installing piston and connecting rod assem-

blies into the bore, install the piston rings.

2. Immerse the piston head and rings in clean engine

oil. Position a ring compressor (3) over the piston
and rings. Tighten ring compressor. Ensure posi-
tion of rings do not change during this opera-
tion.

3. Position bearing onto connecting rod. Ensure that

hole in bearing shell aligns with hole in connecting
rod. Lubricate bearing surface with clean engine
oil.

4. Install Special Tool 8507 Connecting Rod Guides

(4) into connecting rod bolt threads.

5. The pistons are marked on the piston pin bore sur-

face with an raised “F” indicating installation posi-
tion (1). This mark must be pointing toward the
front of engine on both cylinder banks. The con-
necting rod oil slinger slot faces the front of the
engine.

6. Wipe cylinder bore clean and lubricate with engine

oil.

7. Rotate crankshaft until connecting rod journal is on

the center of cylinder bore. Insert rod and piston
into cylinder bore and carefully position connecting
rod guides over crankshaft journal.

8. Tap piston down in cylinder bore using a hammer

handle. While at the same time, guide connecting
rod into position on rod journal.

CAUTION: Connecting Rod Bolts are Torque to
Yield Bolts and Must Not Be Reused. Always
replace the Rod Bolts whenever they are loosened
or removed.

9. Lubricate rod bolts and bearing surfaces with

engine oil. Install connecting rod cap and bearing.
Tighten bolts to 27 N·m (20 ft. lbs.) plus 90°.

10. Install the following components:

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ENGINE - 3.7L - SERVICE INFORMATION

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•

Cylinder head(s). (Refer to 9 - ENGINE/CYLINDER HEAD - INSTALLATION).

•

Timing chain and cover. (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTAL-
LATION).

•

Cylinder head covers (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLA-
TION).

•

Oil pan and gasket/windage tray. (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - INSTALLATION).

11. Fill crankcase with proper engine oil to correct level.

12. Connect negative cable to battery.

RINGS - PISTON

STANDARD PROCEDURE - PISTON RING FITTING

Before reinstalling used rings or installing new rings,
the ring clearances must be checked.

1. Wipe the cylinder bore clean.

2. Insert the ring in the cylinder bore.

NOTE: The ring gap measurement must be made
with the ring positioned at least 12mm (0.50 inch.)
from bottom of cylinder bore.

3. Using a piston, to ensure that the ring is squared in

the cylinder bore, slide the ring downward into the
cylinder.

4. Using a feeler gauge (1) check the ring end gap.

Replace any rings not within specification.

PISTON RING SIDE CLEARANCE

NOTE: Make sure the piston ring grooves are
clean and free of nicks and burrs.

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ENGINE - 3.7L - SERVICE INFORMATION

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5. Measure the ring side clearance as shown make sure the feeler gauge (1) fits snugly between the ring land and

the ring. Replace any ring not within specification.

6. Rotate the ring around the piston, the ring must rotate in the groove with out binding.

PISTON RING SPECIFICATION CHART

Ring Position

Groove Clearance

Maximum Clearance

Upper Ring

.051-.094 mm

0.11 mm

(0.0020-.0037 in.)

(0.004 in.)

Intermediate Ring

0.04-0.08 mm

0.10 mm

(0.0016-0.0031 in.)

(0.004 in.)

Oil Control Ring

.019-.229 mm

.25 mm

(Steel Rails)

(.0007-.0090 in.)

(0.010 in.)

Ring Position

Ring Gap

Wear Limit

Upper Ring

0.20-0.36 mm

0.43 mm

(0.0079-0.0142 in.)

(0.0017 in.)

Intermediate Ring

0.37-0.63 mm

0.74 mm

(0.0146-0.0249 in.)

(0.029 in.)

Oil Control Ring

0.025-0.76 mm

1.55 mm

(Steel Rail)

(0.0099- 0.03 in.)

(0.061 in.)

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

cross section. Ensure No. 2 ring is installed with
manufacturers I.D. mark (Dot) facing up, towards
top of the piston.

NOTE: Piston rings are installed 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.

8. Install the oil ring expander.

9. Install upper side rail (1) by placing one end

between the piston ring groove and the expander
ring. Hold end firmly and press down the portion to
be installed until side rail is in position. Repeat this step for the lower side rail.

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ENGINE - 3.7L - SERVICE INFORMATION

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10. Install No. 2 intermediate piston ring using a pis-

ton ring installer.

11. Install No. 1 upper piston ring using a piston ring

installer.

12. Position piston ring end gaps as shown in. It is

important that expander ring gap (5) is at least
45° from the side rail gaps, but not on the piston
pin center or on the thrust direction.

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ENGINE - 3.7L - SERVICE INFORMATION

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