Dodge Dakota Sport 2001 Service Manual page 1264

AN
INTAKE/EXHAUST VALVES & SEATS (Continued)
VALVE FACE AND VALVE SEAT ANGLE CHART
ITEM DESCRIPTION
A SEAT WIDTH
INTAKE
EXHAUST
B FACE ANGLE
(INT. AND EXT.)
C SEAT ANGLE
(INT. AND EXT.)
D CONTACT
SURFACE
VALVES
Inspect the remaining margin after the valves are
refaced (Fig. 12). Valves with less than 1.190 mm
(0.047 in.) margin should be discarded.
Fig. 12 Intake and Exhaust Valves
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4 - FACE
VALVE SEATS
CAUTION: DO NOT un-shroud valves during valve
seat refacing (Fig. 13).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseating
stones. A true and complete surface must be obtained.
SPECIFICATION
1.016 - 1.524 mm
(0.040 - 0.060 in.)
1.524 - 2.032 mm
(0.060 - 0.080 in.)
43¼° - 43¾°
44¼° - 44¾°
—
Fig. 13 Refacing Valve Seats
1 - STONE
2 - PILOT
3 - VALVE SEAT
4 - SHROUD
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat with Prussian blue, to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15° stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60° stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
in.). The width of the exhaust seats should be 1.524-
2.032 mm (0.060-0.080 in.).
VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 in.. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 in. mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 14). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
ENGINE 5.9L 9 - 235