1998 DODGE RAM 1500 seats

INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves are made of heat resistant steel, and
have chrome plated stems to prevent scuffing. The
intake and exhaust valves are both similar in head
diameter and overall length, but they have unique
face angles which makes them non-interchangeable.
The valves are distinguished by unique dimples on
the exhaust valve head (Fig. 21).
The exhaust valve springs are made from high
strength, chrome silicon steel. The exhaust valve
springs are also exhaust brake compatible.
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVES, GUIDES
AND SPRINGS
REMOVAL
(1) Remove cylinder head (Refer to 9 - ENGINE/
CYLINDER HEAD - REMOVAL).
(2) Support cylinder head on stands, or install
head bolts upside down (through combustion surface
side) to protect injector tips from damage from work
bench.
(3) Install the valve spring compressor mounting
base as shown in (Fig. 22).
(4) Install the compressor top plate, washer, and
nut. Using a suitable wrench, tighten the nut (clock-
wise) to compress the valve springs (Fig. 23) and
remove the locks.
Fig. 22 Spring Compressor Mounting BaseÐPart of
Tool 8319±A
1 - COMPRESSOR MOUNTING BASE
Fig. 23 Compressing Valve Springs with Tool
8319±A
1 - SPECIAL TOOL 8319
Fig. 21 Valve Identification
1 - INTAKE VALVES
2 - EXHAUST VALVES
9 - 256 ENGINE 5.9L DIESELDR

(5) Rotate the compressor nut counter-clockwise to
relieve tension on the springs. Remove the spring
compressor.
(6) Remove the retainers, springs, valve seals (if
necessary), and valves (Fig. 24). Arrange or number
all components so they can be installed in their orig-
inal locations.
(7) Repeat the procedure on all cylinders to be ser-
viced.
CLEANING
Clean the valve stems with crocus cloth or a
Scotch-BriteŸ pad. Remove carbon with a soft wire
brush. Clean valves, springs, retainers, and valve
retaining locks in a suitable solvent. Rinse in hot
water and blow dry with compressed air.
INSPECTION
Visually inspect the valves for abnormal wear on
the heads, stems, and tips. Replace any valve that is
worn out or bent (Fig. 25).
Measure the valve stem diameter in three places
as shown in (Fig. 26).
Measure the cylinder head valve guide bore (Fig.
27).
VALVE GUIDE BORE SPECIFICATIONS
VALVE GUIDE BORE SPECIFICATIONS
Valve guide bore
diameter
Min. 7.027 mm (0.2767 in.)
Max. 7.077 mm (0.2786 in.)
Installed valve guide
depth
Intake
Min. 0.584 mm ( 0.023 in.)
Max. 1.092 mm ( 0.043 in.)
Exhaust
Min. 0.965 mm ( 0.028 in.)
Max. 1.473 mm (0.058 in.)
Fig. 24 Valve Spring, Seal, and Retainers
1 - VALVE RETAINING LOCKS
2 - VALVE
3 - SEAL
4 - SPRING
5 - RETAINER
Fig. 25 Visually Inspect Valves for Abnormal Wear
Fig. 26 Measure Valve Stem Diameter
VALVE STEM DIAMETER
6.96 mm (0.2740 in.) MIN
7.010 mm (0.2760 in.) MAX
DRENGINE 5.9L DIESEL 9 - 257
INTAKE/EXHAUST VALVES & SEATS (Continued)

Measure valve margin (rim thickness) (Fig. 28).
Measure the valve spring free length and maxi-
mum inclination (Fig. 29).
Test valve spring force with tool C-647 (Fig. 30).
Specification 72.0 Ð 80.7 lbs. when compressed to
35.33 mm (1.39 in.).
Fig. 27 Measure Valve Guide Bore
Fig. 28 Measure Valve Margin (Rim Thickness)
VALVE MARGIN (RIM THICKNESS)
0.79 mm (0.031 in.) MIN.
Fig. 29 Measure Valve Spring Free Length and Max.
Inclination
APPROXIMATE VALVE SPRING FREE LENGTH
47.75 mm (1.88 in.)
MAX INCLINATION
1.5 mm (.059 in.)
Fig. 30 Testing Valve Spring with Tool C-647
1 - SPECIAL TOOL C-647
9 - 258 ENGINE 5.9L DIESELDR
INTAKE/EXHAUST VALVES & SEATS (Continued)

INSTALLATION
(1) Install new valve seals. The yellow seals are for
the intake valves and the green seals are for the
exhaust valves.
(2) Install the valves in their original postion. The
exhaust valves are identified by a dimple on the
valve head (Fig. 31).
(3) Install the valve springs and retainer.
(4) Install the valve spring compressor tool 8319±A
as shown in (Fig. 22) and (Fig. 23).
(5) Compress the valve springs and install the
valve retaining locks (Fig. 24).
(6) Remove the compressor and repeat the proce-
dure on the remaining cylinders.
(7) Install new o-ring and sealing washer on injec-
tor.
(8) Lubricate o-ring and injector bore.
(9) Verify sealing washer (shim) was removed with
old injector.
(10) Install injector Refer to (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
INSTALLATION).
(11) Install the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - INSTALLATION).
STANDARD PROCEDURE - VALVE LASH
ADJUSTMENT AND VERIFICATION
NOTE: To obtain accurate readings, valve lash mea-
surements AND adjustments should only be per-
formed when the engine coolant temperature is less
than 60É C (140É F).
The 24±valve overhead system is a ªlow-mainte-
nanceº design. Routine adjustments are no longer
necessary, however, measurement should still takeplace when trouble-shooting performance problems,
or upon completion of a repair that includes removal
and installation of the valve train components or
injectors.
(1) Disconnect battery negative cables.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Using the crankshaft barring tool #7471±B,
rotate crankshaft to align damper TDC mark to
12:00 o'clock position.
(a) If both number one cylinder rocker levers are
loose, continue to next step.
(b) If both number one clylinder rocker levers
are not loose, rotate crankshaft 360 degrees.
(4) With the engine in this position, valve lash can
be measured at the following rocker arms:INTAKE
1±2±4 / EXHAUST 1±3±5. Measure the valve lash by
inserting a feeler gauge between the rocker arm
socket and crosshead (Fig. 32). Refer to VALVE
LASH LIMIT CHART for the correct specifications. If
the measurement fallswithinthe limits, adjust-
ment/resettingis notnecessary. If measurement
finds the lashoutsideof the limits, adjustment/re-
settingisrequired.
VALVE LASH LIMIT CHART
INTAKE EXHAUST
0.152 mm ( 0.006 in.)
MIN.0.381 mm (0.015 in.)
MIN.
0.381 mm (0.015 in.)
MAX.0.762 mm (0.030 in.)
MAX.
note:
If measured valve lash falls within these
specifications, no adjustment/reset is necessary.
Engine operation within these ranges has no adverse
affect on performance, emissions, fuel economy or
level of engine noise.
(5) If adjustment/resetting is required, loosen the
lock nut on rocker arms and turn the adjusting screw
until the desired lash is obtained:
²INTAKE0.254 mm (0.010 in.)
²EXHAUST0.508 mm (0.020 in.) Tighten the
lock nut to 24 Nm (18 ft. lbs.) and re-check the valve
lash.
(6) Using the crankshaft barring tool, rotate the
crankshaftone revolution (360É) to align the
damper TDC mark to the 12 o'clock position.
Fig. 31 Valve Identification
1 - INTAKE VALVES
2 - EXHAUST VALVES
DRENGINE 5.9L DIESEL 9 - 259
INTAKE/EXHAUST VALVES & SEATS (Continued)

(7) With the engine in this position, valve lash can
be measured at the remaining rocker arms:INTAKE
3±5±6 / EXHAUST 2±4±6. Use the same method as
above for determining whether adjustment is neces-
sary, and adjust those that are found to be outside of
the limits.
(8) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(9) Connect the battery negative cables.
REMOVAL - VALVE SPRINGS AND SEALS
(1) Disconnect the battery negative cables.
(2) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Disconnect rocker housing injector harness con-
nector. Remove all injector harness solenoid nuts.
(4) Remove injector(s) for cylinder(s) to be serviced.
Refer to Group 14 for injector removal.
(5) Remove the rocker housing.
(6) Remove the rocker arms and crossheads from
the cylinder(s) to be serviced. Mark each component
so they can be installed in their original position.
(7) Using the crankshaft barring tool #7471±B
(Fig. 33), rotate the engine to position the damper
mark in the 12 o'clock position.At this engine posi-
tion, cylinders #1 and #6 can be serviced.
(8) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(9) With the damper TDC mark in the 12 o'clock
position, add a paint mark anywhere on the gear
housing cover next to the crankshaft damper. Place
another mark on the vibration damper in alignment
with the mark you just made on the cover.(10) Divide the crankshaft damper into three
equally sized segments as follows:
(a) Using a tape measure, measure the circum-
ference of the crankshaft damper and divide the
measurement by three (3).
(b) Measure that distance in a counter-clockwise
direction from the first balancer mark and place
another mark on the balancer.
(c) From the second damper mark, again mea-
sure in a counter-clockwise direction and place a
mark on the damper at the same distance you
measured when placing the second damper mark.
The damper should now be marked in three
equally spaced locations and the damper TDC
mark should be in the 12 o'clock position.
(d) Remove injectors, fuel lines, and high pres-
sure connectors for every cylinder that requires
repair.
(11) Compress the valve springs at cyls. #1 and #6
as follows:
(a) Install the valve spring compressor mounting
base as shown in (Fig. 34).
(b) Install the top plate, washer, and nut. Using
a suitable wrench tighten the nut (clock-wise) (Fig.
35) to compress the valve springs and remove the
collets.
(c) Rotate the compressor nut counter-clockwise
to relieve tension on springs. Remove spring com-
pressor.
(d) Remove and replace retainers, springs, and
seals as necessary.
(e)Do not rotate the engine until the
springs and retainers are re-installed.
(f) Install seals, springs and retainers. Install
spring compressor, compress valve springs and
install the collets.
Fig. 32 Measuring Valve Lash - Typical
1 - INTAKE
2 - FEELER GAUGE
3 - EXHAUST
Fig. 33 Rotating Engine with Barring Tool - Typical
1 - REAR FLANGE
2 - BARRING TOOL
9 - 260 ENGINE 5.9L DIESELDR
INTAKE/EXHAUST VALVES & SEATS (Continued)

(g) Release the spring tension and remove the
compressor. Verify that the collets are seated by
tapping on the valve stem with a plastic hammer.
(12) Using the crankshaft barring tool, rotate the
engine until the next crankshaft damper paint mark
aligns with the mark you placed on the cover.In this
position, cylinders #2 and #5 can be serviced.
(13) Repeat the valve spring compressing proce-
dure previously performed and service the retainers,
springs, and seals as necessary.
(14) Using the crankshaft barring tool, rotate the
engine until the next crankshaft damper paint mark
aligns with the mark you placed on the cover.In this
position, cylinders #3 and #4 can be serviced.
(15) Repeat the spring compressing procedure pre-
viously performed and service the retainers, springs,
and seals as necessary.
INSTALLATION
(1) Install rocker housing.
(2) Install fuel injectors and high pressure fuel
lines.
(3) Lubricate the valve tips and install the cross-
heads in their original locations.
(4) Lubricate the crossheads and push rod sockets
and install the rocker arms and pedestals in their
original locations. Tighten bolts to 36 N´m (27 ft. lbs.)
torque.
(5)Verify valve lash adjustment (Refer to 9 -
ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE).
(6) Install cylinder head cover and reusable gasket
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - INSTALLATION).
(7) Connect battery negative cables.
ROCKER ARM / ADJUSTER
ASSY
DESCRIPTION
The unique intake and exhaust rocker arms have
their own rocker shafts and are lubricated by pas-
sages intersecting the cylinder block main oil rifle.
Crossheads are used, which allow each rocker arm to
operate two valves.
The solid push rods are hardened at the rocker
arm and tappet contact areas for superior strength
and durability.
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Remove the rocker arm/pedestal fasteners (Fig.
36) and remove rocker arm and pedestal from cylin-
der head. Mark the arms and pedestals so they can
be installed in their original position.
CAUTION: When removing the rocker arms, the
sockets (Fig. 37) may come loose and fall into the
engine. Make sure they stay with the arm upon
removal/installation.
(4) Lift the push rod(s) up and out of the engine
(Fig. 38). Mark them so they can be installed in their
original position.
Fig. 34 Spring Compressor Mounting BaseÐPart of
Tool 8319±A
1 - COMPRESSOR MOUNTING BASE
Fig. 35 Compressing Valve Springs with Tool
8319±A
1 - SPECIAL TOOL 8319
DRENGINE 5.9L DIESEL 9 - 261
INTAKE/EXHAUST VALVES & SEATS (Continued)

Push Rods
Inspect the push rod ball and socket for signs of
scoring. Check for cracks where the ball and the
socket are pressed into the tube (Fig. 41).
Roll the push rod on a flat work surface with the
socket end hanging off the edge (Fig. 42). Replace
any push rod that appears to be bent.
Crossheads
Inspect the crossheads for cracks and/or excessive
wear on rocker lever and valve tip mating surfaces
(Fig. 43).
INSTALLATION
(1) If previously removed, install the push rods in
their original location.Verify that they are seated
in the tappets.(2) Lubricate the valve tips and install the cross-
heads in their original locations.
(3) Lubricate the crossheads and push rod sockets
and install the rocker arms and pedestals in their
original locations. Tighten bolts to 36 N´m (27 ft. lbs.)
torque.
(4)Verify valve lash adjustment (Refer to 9 -
ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE).
(5) Install cylinder head cover and reusable gasket
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - INSTALLATION).
(6) Connect battery negative cables.
Fig. 40 Measuring Rocker Arm Shaft
ROCKER ARM SHAFT (MIN.)
21.965 mm (.865 in.)
Fig. 41 Inspecting Push Rod for Cracks
Fig. 42 Inspecting Push Rod for Flatness
Fig. 43 Inspecting Crosshead for Cracks
DRENGINE 5.9L DIESEL 9 - 263
ROCKER ARM / ADJUSTER ASSY (Continued)

(6) Remove the wooden dowel rods and rubber
bands from the tappets.
(7) Lubricate the push rods with engine oil and
install in their original location.Verify that they
are seated in the tappets.
(8) Lubricate the valve tips with engine oil and
install the crossheads in their original locations.
(9) Lubricate the crossheads and push rod sockets
with engine oil and install the rocker arms and ped-
estals in their original locations. Tighten bolts to 36
N´m (27 ft. lbs.) torque.
(10)Verify valve lash adjustment (Refer to 9 -
ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE).
(11) Install the cylinder head cover and reusable
gasket (Refer to 9 - ENGINE/CYLINDER HEAD/
CYLINDER HEAD COVER(S) - INSTALLATION).
(12) Install gear housing cover (Refer to 9 -
ENGINE/VALVE TIMING/GEAR HOUSING COVER
- INSTALLATION). Install front crankshaft dust
seal.
(13) Install the crankshaft damper with the speed
indicator ring (Refer to 9 - ENGINE/ENGINE
BLOCK/VIBRATION DAMPER - INSTALLATION).
(14) Install the fan support/hub assembly Refer to
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(15) Install the power steering pump.
(16) Install accessory drive belt tensioner. Torque
bolt to 43 Nm (32 ft. lbs.).
(17) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(18) Install the charge air cooler (with a/c con-
denser and auxiliary transmission oil cooler, if
equipped) and tighten the mounting bolts to 2 N´m
(17 in. lbs.) torque.
(19) Connect charge air cooler inlet and outlet
pipes. Tighten clamps to 11 N´m (95 in. lbs.) torque.
(20) Install the radiator upper support panel.
(21) Close radiator petcock and lower the radiator
into the engine compartment. Tighten the mounting
bolts to 11 N´m (95 in. lbs.) torque.
(22) Raise vehicle on hoist.
(23) Connect radiator lower hose and install
clamp.
(24) Connect transmission auxiliary oil cooler lines
(if equipped).
(25) Lower vehicle.
(26) Install the fan shroud and tighten the mount-
ing screws to 6 N´m (50 in. lbs.) torque.
(27) Install the electronically controlled viscous
fan/drive assembly. Connect harness connector.(Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).(28) Install the coolant recovery and windshield
washer fluid reservoirs to the fan shroud.
(29) Connect the coolant recovery hose to the radi-
ator filler neck.
(30) Add engine coolant (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(31) Charge A/C system with refrigerant (if A/C
equipped) (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - STANDARD PROCEDURE).
(32) Connect the battery negative cables.
(33) Start engine and check for engine oil and cool-
ant leaks.
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING ROD
BEARING AND CRANKSHAFT JOURNAL
CLEARANCE
(1) Measure the connecting rod bore with bearings
removedand the bolts tightened to 100 N´m (73 ft.
lbs.) torque..
(2) Measure the connecting rod bore with the bear-
ingsinstalledand the bolts tightened to 100 N´m
(73 ft. lbs.) torque.
Measure within 20É arc from each side of the part-
ing line. Also measure 90É from parting line.
Record the smallest and largest diameter.
Measure the diameter of the rod journal at the
location shown (Fig. 63). Calculate the average diam-
eter for each side of the journal.
Determine minimum bearing clearance by calculat-
ing the differance between the smallest connecting
rod bore diameter with the bearing installed and the
average diameter for each side of the crankshaft jour-
nal.
Determine the maximum bearing clearance by cal-
culating the difference between the largest connect-
ing rod bore diameter and the average diameter with
the bearing installed for each side of the crankshaft
journal.
DESCRIPTION MEASUREMENT
CONNECTING ROD
BORE, BEARINGS
REMOVEDMIN. 72.99 mm (2.874
in.)
MAX. 73.01 mm (2.875
in.)
CONNECTING ROD
BORE, BEARINGS
INSTALLEDMIN. 69.05 mm (2.719
in.)
MAX. 69.10 mm (2.720
in.)
9 - 272 ENGINE 5.9L DIESELDR
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)