TESTING VALVE SPRINGS
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
should be tested Special Tool C-647. As an example,
the compression length of the spring to be tested is
33.34 mm (1-5/16 in.). Turn tool table until surface is
in line with the 33.34 mm (1-5/16 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over stud on the table and lift compressing
lever to set tone device (Fig. 64). Pull on torque
wrench until ping is heard. Take reading on torque
wrench at this instant. Multiply this reading by two.
This will give the spring load at test length. Frac-
tional measurements are indicated on the table for
finer adjustments. Discard the springs that do not
meet specifications. The following specifications apply
to both intake and exhaust valve springs:
• Valve Closed Nominal Tension—70 lbs. @ 39.8
mm (1.57 in.)
• Valve Closed Nominal Tension—160 lbs. @ 32.6
mm (1.28 in.)
(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 in.) 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. 65). Intake valves with less than
0.95 mm (1/32 in.) margin and exhaust valves with
less than 1.05 mm (3/64 in.) margin should be dis-
carded.
(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. For specifications, refer to Engine Specifi-
cations in this section.
(4) Measure the concentricity of valve seat and
valve guide using a valve seat runout dial indicator.
Total runout should not exceed. 0.051 mm (0.002 in.)
(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.
Fig. 63 Valve Guide Height
1 – VALVE GUIDE
2 – 13.25 - 13.75 MM
(.521 -.541 IN.)
3 – SPRING SEAT
Fig. 64 Valve Spring Testing
1 – TORQUE WRENCH
2 – VALVE SPRING TESTER
Fig. 65 Intake and Exhaust Valve Refacing
1 – VALVE FACE
2 – VALVE MARGIN
JX
2.0L SOHC ENGINE
9 - 37
REMOVAL AND INSTALLATION (Continued)