Valves; Refacing Valves; Select Fitting Valves; Camshaft - Lincoln Continental 1964 Shop Manual

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remove stock from the top of the
seats (lower the seats) .
The finished valve seat should
contact the approximate center of
the valve face. It is good practice to
determine where the valve seat con-
tacts the face. To do this, coat the
seat with Prussian blue, then set
the valve in place. Rotate the valve
with light pressure. If the blue is
transferred to the center of the
valve face, the contact is satisfac-
tory. If the blue is transferred to
the top edge of the valve face,
lower the valve seat. If the blue is
transferred to the bottom edge of
the valve face, raise the valve seat.
VALVES
Valve defects, such as minor pits,
grooves, etc., may be removed by re-
facing the valves. Discard valves that
are severely damaged, or if the face
runout or stem clearance exceed spe-
cifications.
Discard any defective part of the
valve assembly.
REFACING VALVES
The valve refacing operation
should be closely coordinated with
the valve seat refacing operation so
that the finished angles of the valve
face and of the valve seat will pro-
vide a compression-tight fit. Be sure
that the refacer grinding wheels are
properly dressed.
If the valve face runout is exces-
sive and/ or to remove pits and
grooves, reface the valves to a true
44 ° angle. Remove only enough
stock to correct the runout or to
clean up the pits and grooves. If the
edge of the valve head is less than
%2
inch after grinding, replace the
valve as the valve will run too hot in
the engine. The interference fit of
the valve and seat should not be
lapped out.
Remove all grooves or score
marks from the end of the valve
stem, then chamfer as necessary.
Do not remove more than 0.010
inch from the stem.
If the valve and/ or valve seat has
been refaced, it will be necessary to
check the clearance between the
rocker arm pad and the valve stem
with the valve train assembly in-
stalled in the engine.
SELECT FITTING VALVES
If the valve stem to valve guide
clearance exceeds the wear limit,
PART 8-1-GENERAL ENGINE SERVICE
ream the valve guide for the next
oversize valve stem. Valves with
oversize stem diameters of 0.003,
0.015, and 0.030 inch are available
for service. Always reface the
valve seat after the valve guide
has been reamed. Refer to "Ream-
ing Valves Guides."
CAMSHAFT
Remove light scuffs, scores, or
nicks from the camshaft machined
surfaces with a smooth oil stone.
CRANKSHAFT
Dress minor imperfections with an
oil stone. Reface severely marred
journals.
If the journals exceed the wear
limit, they should be refinished to
size for the next undersize bearing.
REFINISHING JOURNALS
Refinish the journal to give the
proper clearance with the next under-
size bearing. If the journal wil1 not
"clean up" to give the proper clear-
ance with the maximum undersize
bearing available, replace the crank-
shaft.
Always reproduce the same jour-
nal shoulder radius that existed
originally. Too small a radius will
result in fatigue failure of the crank-
shaft. Too large a radius will result
in bearing failure due to radius ride
of the bearing.
After refinishing the journals,
chamfer the oil holes, then polish
the journal with a No. 320 grit
polishing cloth and engine oil.
Crocus cloth may be used also as a
polishing agent.
PISTONS, PINS AND RINGS
FITTING PISTONS
Pistons are available for service in
standard sizes and 0.020 and 0.030
inch oversizes. The standard size pis-
tons are color coded on the dome as
follows: red, 4.2977-4.2983 inch;
blue, 4.2989-4.2995 inch.
If the piston clearance is greater
than the maximum limit, recheck
calculations to be sure that the prop-
er size piston has been selected,
check for a damaged piston, then
try a new piston.
If the clearance is less than the
minimum limit, recheck calculations
before trying another piston. If none
can be fitted, refinish the cylinder for
the size piston available.
8-11
When a piston has been fitted,
mark it for assembly in the cylin-
der to which it was fitted.
If the taper and out-of-round con-
ditions of the cylinder bore are with-
in limits, new piston rings will give
satisfactory service provided the pis-
ton clearance in the cylinder bore is
within limits. If the new rings are to
be installed in a used cylinder that
has not been refinished, remove the
cylinder wall "glaze."
To fit a piston:
1. Calculate the size piston to be
used by taking a cylinder bore check
(Fig. 23).
2. Select the proper size piston to
provide the desired clearance (Fig.
9).
3. Make sure the piston and cyl-
inder block are at room temprature
(70°F). After any refinishing op-
eration, allow the cylinder bore to
cool and make sure the piston and
bore are clean and dry before the
piston fit is checked.
4. Attach a tension scale to the
end of a feeler gauge ribbon that is
free of dents or burrs. The feeler
ribbon should be 1h -inch wide and
of one of the thicknesses listed in
Fig. 9.
5. Position the ribbon in the cyl-
inder bore so that it extends the ·
entire length of the piston at 90°
from the piston pin location.
6. Invert the piston· and install it
in the bore so that the end of the
piston is about llh inches below the
top of the cylinder block and the
piston pin is parallel to the crank-
shaft axis.
7. Hold the piston and slowly pull
the scale in a straight line with the
ribbon, noting the pull required to
remove the feeler ribbon (Fig. 10).
Compare the required pull with
Fig. 9 to determine the piston clear-
ance.
FITTING PISTON RINGS
1. Select the proper ring set for
the size piston to be used.
2. Position the ring in the cylinder
bore in which it is going to be used.
3. Push the ring down into the
bore area where normal ring wear is
not encountered.
4. Use the head of a piston to
position the ring in the bore so that
the ring is square with the cylinder
wall. Use caution to avoid damage
to the ring or cylinder bore.