Dodge Dakota Sport 2001 Service Manual page 1056

AN
INTAKE/EXHAUST VALVES & SEATS (Continued)
Fig. 20 Intake and Exhaust Valves
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4 - FACE
VALVE SEAT REFACING
CAUTION: DO NOT un-shroud valves during valve
seat refacing (Fig. 21).
Fig. 21 Refacing Valve Seats
1 - STONE
2 - PILOT
3 - VALVE SEAT
4 - SHROUD
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(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.).
REMOVAL—VALVES
NOTE: This procedure is done with the head
removed.
(1) Compress valve springs using Valve Spring
Compressor Tool MD-998772-A and adapter 6716A.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals, and valve springs.
(3) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original locations.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSTALLATION—VALVES
(1) Coat valve stems with lubrication oil and insert
them in cylinder head.
(2) If valves or seats are reground, check valve stem
height. If valve is too long, replace cylinder head.
(3) Install new seals on all valve guides. Install
valve springs and valve retainers.
(4) Compress valve springs with Valve Spring
Compressor Tool MD-998772A and adapter 6716A,
install locks and release tool. If valves and/or seats
are ground, measure the installed height of springs.
Be sure the measurement is taken from bottom of
spring seat in cylinder head to the bottom surface of
spring retainer. If spacers are installed, measure
from the top of spacer. If height is greater than 42.86
mm (1-11/16 inches), install a 1.587 mm (1/16 in.)
spacer in head counterbore. This should bring spring
height back to normal 41.27 to 42.86 mm (1-5/8 to
1-11/16 in.).
ENGINE 2.5L 9 - 27