Chrysler neon 1997 Service Manual page 1214

PL
DISASSEMBLY AND ASSEMBLY (Continued)
(2) Verify springs are not distorted with a steel
square and surface plate, check springs from both
ends. If the spring is more than 1.5 mm (1/16 inch)
out of square, install a new spring.
REFACING VALVES AND VALVE SEATS
(1) The intake and exhaust valve seats and valve
face have a 45 degree angle.
(2) Inspect the remaining margin after the valves
are refaced (Fig. 95). Intake valves with less than
0.95 mm (1/32 inch.) margin and Exhaust valves
with less than 1.05 mm (3/64 inch) margin should be
discarded.
Fig. 95 Refacing Intake and Exhaust Valves
(3) 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 See (Fig. 96) for valve specification.
Fig. 96 Valve Specifications
(4) Measure the concentricity of valve seat and
valve guide using a valve seat runout dial indicator.
VALVE MARGIN VALVE FACE
Total runout should not exceed. 0.051 mm (0.002
inch.) (total indicator reading).
(5) 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 top edge of the valve face, lower valve seat
with a 15 degrees stone. If the blue is transferred to
the bottom edge of valve face raise valve seat with a
65 degrees stone.
• Intake valve seat diameter is 33 mm (1.299 in.)
• Exhaust valve seat diameter is 28 mm (1.102
in.)
(6) Valve seats which are worn or burned can be
reworked, provided that correct angle and seat width
are maintained. The intake valve seat must be ser-
viced when the valve seat width is 2.0 mm (0.079 in.)
or greater. The exhaust valve seat must be serviced
when the valve seat width is 2.5 mm (0.098 in.) or
greater. Otherwise the cylinder head must be IN.) A — SEAT WIDTH (INTAKE AND EXHAUST 0.9 TO 1.3 mm (.035 TO .051 B — FACE ANGLE (INTAKE & EXHAUST: 44 C — SEAT ANGLE (INTAKE & EXHAUST: 45°-45 D — SEAT CONTACT AREA E — SEAT DIAMETER
replaced.
(7) When seat is properly positioned the width of
intake and exhaust seats should be 0.75 to 1.25 mm
(0.030 to 0.049 in.) (Fig. 97).
Fig. 97 Refacing Valve Seats
(8) Check valve tip to spring seat dimensions A
after grinding the valve seats or faces. Grind valve
tip to 43.51 - 44.57 mm (1.71 - 1.75 in.) for exhaust
valve and 45.01 - 46.07 mm (1.77 - 1.81 in.) for
intake valve over spring seat when installed in the
head (Fig. 98). The valve tip chamfer may need to be
reground to prevent seal damage when the valve is
installed.
CLEANING
Clean all valve guides, valves and valve spring
assemblies thoroughly with suitable cleaning solution
before reassembling.
2.0L SOHC ENGINE
1 ⁄ °–45°) 1 ⁄ °)
2 2
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