Dodge ram truck 3500 1996 Service Manual page 1158

i - 168 5 J L (DIESEL) ENGINE
B R
SERVICE PROCEDURES (Continued)
Lubricate the valve guides with oil and press in
the guides to 12.25 ±0.50 mm (0.4823 ±0.020 inch)
protrusion above the cylinder head.
Ream the bores to 8.029 ±0.010 mm (0.3161
±0.0004 inch) - (Fig. 6).
VALVE GUIDE BORES
EXHAUST
CYLINDER
HEAD
INTAKE
CYLINDER HEAD VALVE GUIDE BORES
CYLINDER HEAD VALVE GUIDE BORES
14.0O) ±0.013 m m (0.5512 ± 0.0005 in)
VALVE GUIDE BORES
8.029 ±0.010 m m (0.3161 ±0.0004 in)
J9109-137
Fig. 6 Service Waive Guides—Thick Wail
XfAiJSfE SEATS
INTEGRAL VALVE SEAT GRINDING
After resurfacing the valves and determining that
all valves meet specifications, install the valves i n
their designated locations and measure valve depth
(Fig. 7). The valve depth is the distance from the
valve face to the head deck. Record the depth of each
valve.
CYLINDER
HEAD DECK
VALVE
FACE
VALVE
DEPTH
J9109-140
Fig. 7 Valve Depth
Grind the valve seats to remove scores, scratches
and burns. The seat angle should be—Intake 30° and
Exhaust 45°.
Install the valves in their respective bores and
measure the depth again (Fig. 7). Record the depth of
each valve.
The grinding depth is the difference between the
measurement before grinding and the measurement
after grinding. The grinding depth maximum limit
(integral seats only) is 0.254 mm (0.010 inch). Service
valve seats are available for over limit integral valve
seats.
Identify ground valve seats by stamping the cylin­
der head.
Install the valves in their designated locations and
measure the depth of each. The valve depth limit
(Integral and Inserted Seats) is 0.99 mm to 1.52 mm
(0.039 inch to 0.060 inch). Replace the valve i f the
depth is over this limit.
Apply a light coat of valve lapping compound to
each valve and lap each valve to its mating seat.
Remove the valves and clean lapping compound
from the valves and seats.
Measure the valve seat width indicated by the lap­
ping surface. The valve seat width limit is 1.50-2.00
mm (0.060-0.080 inch).
I f required, grind the areas with a 60° stone and a
15° stone to center the seat on the valve face. Main­
tain the valve seat width limits (Fig. 8).
VALVE
GRIND TO 15°
J9109-141
Fig. 8 Grind Valve Seat
SERVICE VALVE SEAT INSTALLATION
Inspect the valve guide bores as described in the
Cleaning and Inspection section of this group. I f i t is
necessary to install valve guides, install the guides
before installing the service seats.
Replacement valve seat inserts must be installed i f
the valve seats have been ground previously. The
illustrated marks indicate valve seats have been
ground previously.
Machine the cylinder head to install the service
valve seats (Fig. 9) (Fig. 10).
Press service seats into the machined pockets.
Stake the valve seats into the pockets.