Page 1569 of 5267

4. Install the lower bearing insert in the bearing cap.
Center bearing insert in connecting rod..The
lower insert must be dry. Place strip of Plastigage
across full width of the lower insert at the center of
bearing cap. Plastigage must not crumble in use. If
brittle, obtain fresh stock.
5. Install bearing cap and connecting rod on the jour-
nal and tighten bolts to 27 Nꞏm (20 ft. lbs.) plus a
90° turn. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
6. Remove the bearing cap and determine amount of
bearing-to-journal clearance by measuring the
width of compressed Plastigage (2). Refer to
Engine Specifications for the proper clearance.
Plastigage should indicate the same clearance
across the entire width of the insert. If the
clearancevaries,itmaybecausedbyeithera
tapered journal, bent connecting rod or foreign
material trapped between the insert and cap or
rod.
7. If the correct clearance is indicated, replacement of
the bearing inserts is not necessary. Remove the Plastigage from crankshaft journal and bearing insert. Proceed
with installation.
Bearing Mark SIZE USED WITH JOURNAL SIZE
.025 US.025 mm 57.883-57.867 mm
(.001 in.) (2.2788-2.2783 in.)
Std.STANDARD 57.908-57.892 mm
(2.2798-2.2792 in.)
.250 US.250 mm 57.658-57.646 mm
(.010 in.) (2.2700-2.2695 in.)
8. If bearing-to-journal clearance exceeds the specification, determinwhich services bearing set to use the bearing
sizes are as follows:
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. Repeat the Plastigage measurement to verify your bearing selection prior to final assembly.
10. Once you have selected the proper insert, install the insert and cap. Tighten the connecting rod bolts to 27 Nꞏm
(20 ft. lbs.) plus a 90° turn.
Page 1570 of 5267

Slide snug-fitting feeler gauge between the connecting
rod and crankshaft journal flange. Refer to Engine
Specifications for the proper clearance. Replace the
connecting rod if the side clearance is not within
specification.
STANDARD PROCEDURE - PISTON FITTING
1. To correctly select the proper size piston, a cylinder
bore gauge (2), capable of reading in 0.003 mm (
.0001 in.) INCREMENTS is required. If a bore
gauge is not available, do not use an inside
micrometer.
2. Measure the inside diameter of the cylinder bore
(3) at a point 38.0 mm (1.5 inches) below top of
bore. Start perpendicular (across or at 90 degrees)
to the axis of the crankshaft at point A and then
take an additional bore reading 90 degrees to that
at point B.
3. The coated pistons (1,2) will be serviced with the
piston pin and connecting rod pre-assembled.
4. The coating material is applied to the piston after
the final piston machining process. Measuring the
outside diameter of a coated piston (1,2) will not
provide accurate results. Therefore measuring the
inside diameter of the cylinder bore with a dial Bore
Gauge isMANDATORY. To correctly select the
proper size piston, a cylinder bore gauge capable
of reading in 0.003 mm (.0001 in.) increments is
required.
5. Piston installation intothe cylinder bore requires
slightly more pressure than that required for non-
coated pistons. The bonded coating on the piston
will give the appearance of a line-to-line fit with the
cylinder bore.
Page 1571 of 5267

REMOVAL
1. Disconnect negative cable from battery.
2. Remove the following components:
Oil pan and gasket/windage tray (Refer to 9 - ENGINE/LUBRICATION/OIL PAN -REMOVAL).
Cylinder head covers (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL) and
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL).
Timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL).
Cylinder head(s) (Refer to 9 - ENGINE/CYLINDER HEAD - REMOVAL) and (Refer to 9 - ENGINE/CYLINDER
HEAD - REMOVAL).
3. If necessary, remove top ridge of cylinder bores with a reliable ridge reamer before removing pistons from cyl-
inder block.Be sure to keep tops of pistons covered during this operation.Pistons and connecting rods
must be removed from top of cylinder block. When removing piston and connecting rod assemblies from the
engine, rotate crankshaft so the each connecting rod is centered in cylinder bore.
CAUTION: DO NOT use a number stamp or a punch to mark connecting rods or caps,as damage to con-
necting rods could occur
NOTE: Connecting rods and bearing caps are not interchangeable and shouldbe marked before removing
to ensure correct reassembly.
4. Mark connecting rod and bearing cap positions using a permanent ink marker or scribe tool.
CAUTION: Care must be taken not to damage the fractured rod and cap joint face surfaces, as engine dam-
age may occur.
5. Remove connecting rod cap. Install Special Tool 8507 Connecting Rod Guides into the connecting rod being
removed. Remove piston from cylinder bore. Repeat this procedure for eachpiston being removed.
CAUTION: Care must be taken not to nick crankshaft journals, as engine damage may occur
6. Immediately after piston and connecting rod removal, install bearing cap on the mating connecting rod to prevent
damage to the fractured cap and rod surfaces.
CLEANING
CAUTION: DO NOT use a wire wheel or other abrasive cleaning devise to clean the pistons or connecting
rods. The pistons have a Moly coating, this coating must not be damaged.
1. Using a suitable cleaning solvent clean the pistons in warm water and towel dry.
2. Use a wood or plastic scraper to clean the ring land grooves.
CAUTION: DO NOT remove the piston pin from the piston and connecting rod assembly.
INSPECTION
Check the connecting rod journal for excessive wear, taper and scoring (Refer to 9 - ENGINE/ENGINE BLOCK/
CONNECTING ROD BEARINGS - STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bending.
Check the piston for taper and elliptical shape before it is fitted into thecylinder bore (Refer to 9 - ENGINE/ENGINE
BLOCK/PISTON & CONNECTING ROD - STANDARD PROCEDURE).
Check the piston for scoring, or scraping marks in the piston skirts. Checkthe ring lands for cracks and/or deteri-
oration.
Page 1572 of 5267

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
rodintopositiononrodjournal.
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 Nꞏm (20 ft. lbs.) plus 90°.
10. Install the following components:
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).
Page 1573 of 5267
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.
Page 1574 of 5267

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.
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 without 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
Page 1575 of 5267

Ring Position Groove Clearance Maximum Clearance
(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.
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.
Page 1576 of 5267
12. Position piston ring end gaps as shown. 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.