Ford Thunderbird 1958 User Manual

1-32
GROUP
1-POWER PLANT
TO
REMOVE
STOCK FROM
BOTTOM
OF
EXHAUST
SEAT,
USE
30
WHEEL
TO
REMOVE
STOCK
FROM
TOP
OF
INTAKE
SEAT,
USE
15
WHEEL
TO
REMOVE
STOCK
FROM
TOP
OF
EXHAUST
SEAT,
USE
60
WHEEL
5
OR
60
1738-A
FIG.
66
Valve
Seat
Refacing
FIG.
65
Reaming
Valve Guides
1/32"
MINIMUM
MAXIMUM VALVE
FACE RUNOUT
0.002
.REFER
TO
SPECIFICATIONS
FOR
CORRECT
DIAMETER
S
CHECK
FOR
BENT STEM
DO
NOT
REMOVE MORE
THAN
0.010
INCH
\
45
EXHAUST
30
INTAKE
1739-A
FIG.
67
Critical
Valve
Tolerances
REAMING
VALVE
GUIDES
If
it
becomes
necessary
to
ream a
valve guide
(Fig.
65)
to install
a valve
with
an
oversize
stem,
a
reaming
kit
is
available
which contains
the
follow
ing
reamer
and pilot
combinations;
a
0.003-inch
O.S.
reamer
with
a
stand
ard
diameter
pilot,
a 0.015-inch
O.S.
reamer
with a
0.003-inch
O.S.
pilot,
and
a
0.030-inch
reamer with a
0.015-inch
O.S.
pilot.
When
going
from a standard
size
valve to
an
oversize
valve,
always
use
the
reamers in
sequence.
Always
re
face
the
valve
seat
after
the valve
guide
is
reamed.
REFACING
VALVE
SEATS
Refacing
of
the
valve seats
should
be
closely
coordinated
with
the
re
facing
of
the
valve
face so the
finished
seat
will
match
the valve
face and be
centered.
This
is
important
so that
the
valve
and seat
will have
a
good
com
pression
tight fit.
Be
sure that the
re
facer
grinding
wheels
are
properly
dressed.
Grind the
exhaust
valve
seat to a
true
45
angle
and the
intake
valve
seat to
a
true
30
angle
(Fig.
66).
Remove
only
enough
stock to
clean
up
pits, grooves,
or
to
correct
the
valve
seat
runout.
After the seat is
ground,
measure
the
seat width
(Fig.
64).
Narrow
the
seat,
if
necessary
to
bring
it
within
limits.
If the
valve seat
width
exceeds
the
maximum
limits,
remove
enough
stock from
the
top
edge
and/or
bot
tom
edge
of the
seat to
reduce the
width
to
specifications
(Fig.
66).
On
the
exhaust valve
seat,
use
a
30
angle
grinding
wheel
to remove
stock from
the
bottom of the
seat
(raise
the
seat)
and use
a
60
angle
wheel to
remove
stock
from the
top
of
the
seat
(lower the
seat).
On
the
intake valve
seat,
use a
15
angle
grinding
wheel
to
remove
stock
from the
top
of the
seat
(lower the
seat).
The
finished valve seat should con
tact the
approximate center of
the
valve
face.
To determine where
the
valve seat
contacts
the
face,
coat
the
seat
with Prussian
blue,
then set the
valve
in
place.
Rotate the
valve with
light pressure.
If the blue
is
trans
ferred
to
the
center of the
valve
face,
the
contact
is
satisfactory.
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.
After
refacing
the
valve
seat,
it is
good
practice
to
lightly lap
in the
valve
with a
medium grade
lapping
compound.
Remove
all
the com
pound
from the
valve and seat after
the
lapping
operation.
VALVES
CLEANING
AND
INSPECTION
Remove all
carbon
and
varnish
from the
valve with a fine
wire
brush
or
buffing
wheel.
The
critical
inspec
tion points
and tolerances
of
the
valve
are
illustrated
in Fig.
67.
Inspect
the
valve face
and
the
edge
of the
valve
head for
pits,
grooves,
scores,
or
other
defects.
Inspect the
stem
for a
bent
condition
and
the
end of
the
stem
for
grooves
or
scores.
Check
the valve
head
for
signs
of
burning
or
erosion, warpage,
and
cracking.
Defects,
such
as
minor
pits,
grooves,
etc.
may
be
removed.
Dis
card
valves
that are
severely
dam
aged.
Inspect the
valve springs
and
valve
damper
springs,
valve
spring
retain
ers,
locks,
and
sleeves
for
defects.
Discard
any
defective
parts.

Ford Thunderbird 1958 Specifications

General

Brand	Ford
Model	Thunderbird 1958
Category	Automobile
Language	English