VALVES
Inspect the remaining margin after the valves are
refaced. Refer to Engine Specifications.
VALVE SEATS
(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
dial indicator. Total runout should not exceed 0.051
mm (0.002 inch.) 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 top edge of valve face, then lower valve seat
with a 15 degree stone. If the blue is transferred to
the bottom edge of valve face, then raise valve seat
with a 65 degree stone.
NOTE: Valve seats which are worn or burned can
be reworked, provided that correct angle and seat
width are maintained. Otherwise cylinder head must
be replaced.
(4) When seat is properly positioned the width of
the intake 1.00 to 1.50 mm (0.0394 to 0.0591 in.) and
exhaust seats should be 1.25 to 1.75 mm (0.049 to
0.069 in.) (Fig. 33).
(5) Check the valve spring installed height after
refacing the valve and seat (Fig. 35).
VALVE SPRINGS
The valve springs are common for intake and
exhaust valves. Refer to Engine Specifications.
TESTING VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested (Fig. 34). As an example; the compression
length of the spring to be tested is 38.00 mm (1.496
in.). Turn table of Tool C-647 until surface is in line
with the 38.00 mm (1.496 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. 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. Fractional measure-
ments are indicated on the table for finer adjust-
ments. Refer to Specifications Section to obtain
specified height and allowable tensions. Replace any
springs that do not meet specifications.
VALVE INSTALLATION
(1) Coat valve stems with clean engine oil and
insert them in cylinder head.
(2) If valves or seats have been reground, check
valve tip height (A) (Fig. 35). If valve tip height for
intake valve is greater than 47.59 (1.8737 in.) or
49.14 (1.9347 in.) for exhaust valve, grind valve tip
until within specifications. Make sure measurement
is taken from cylinder head surface to the top of
valve stem.
(3) Install valve seal/spring seat assembly over
valve guides on all valve stems (Fig. 36). Ensure that
Fig. 32 Checking Crankshaft End Play
Fig. 33 Valve Seats
ITEM DESCRIPTION SPECIFICATION
A Seat Width Intake:
1.00 –
1.50 mm
(0.39 –
0.059 in.)
Exhaust:
1.25 – 1.75
mm (0.049
– 0.069 in.)
B Face Angle Intake & Exhaust: 44.5 –
45°
C Seat Angle Intake & Exhaust: 45 –
45.5°
D Seat Contact
Area
Valve to seat contact
must be at center of
valve face.
9 - 28 2.7L ENGINE LH
SERVICE PROCEDURES (Continued)
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