Engine Tune-Up; Clean, Adjust - Ford 1955 Shop Manual

8
Chapter I
General Engine Repair
(1)
ENGINE
OVERHEATS. Usually,
engine
over
heating is
the
result of
insufficient
coolant supply.
Check
the
coolant
level first. Make
certain
that the
cause
of
trouble is
not anti-freeze evaporation.
(a) If
the
supply
is
low,
check
for leaks in
the cooling
system,
make repairs as necessary.
(b)
Check
the
water
pump belt for
proper
tension
and
adjust
if loose.
(c) Inspect
the
radiator
fins for
obstructions
(bugs,
dirt,
etc.)
Clean
if
clogged.
(d) Using
a
thermometer in
the radiator,
check
the
gauge
reading for
accuracy.
NOTE: Inaccurate
readings are sometimes caused
by
insufficient
clearance
between
the
head
casting
and
the temperature
sending
unit element.
Repair
or
re~
place as necessary.
(e)
Check
the thermostat
for
proper operation
and
heat
range.
If defective
or
of
the
wrong
heat
range,
replace
the thermostat.
(f
)
Check
the
ignition
timing and
adjust
if
necessary.
(g)
Check
the
radiator
for
proper
flow. Flush
if
necessary.
(h)
Remove
the
water pump
and check
for
a
defective
impeller
or water passage obstruction.
Repair
or replace
as necessary.
(2)
ENGINE FAILS TO REACH NORMAL OPER
ATING TEMPERATURE.
Generally, this
is
caused
by
the thermostat sticking
or
being
of
the
wrong
heat
range.
Check
the thermostat
first. If
the
engine still
does
not
reach
operating
temperature,
check
the
gauge and sending
unit,
with a
thermometer
in
radiator,
for
accuracy.
Re
place
the
defective
unit.
2.
ENGINE TUNE-UP
During the
life
of an automotive
vehicle,
it
should
receive regular maintenance
and
inspection
services.
However,
to
maintain
satisfactory performance,
an engine
tune-up
should
be
performed periodically.
Any type
of engine
test
equipment
may
be
used
to
make
the tests
outlined
in
the
checking procedures.
As
the
checks are
performed,
make a visual
inspection
of
the wiring,
vacuum
hose,
cooling
system
hose,
heater
hoses,
etc.
a.
Minor Tune-Up.
A
minor
tune-up
consists of
the
following
operations:
(1)
INSPECT IGNITION WIRES,
BATTERY
CABLES,
AND CHECK CONDITION OF THE BAT
TERY. Inspect
all
ignition
cables
for
worn or
damaged
insulation. Make
sure
that the
spark
plug
wires are
firmly
seated
in
the
distributor cap
and
that the terminals
and
terminal
sockets are
free from
corrosion.
Inspect
the battery
case
for
cracks and
leaks. Check
the
water
level in
the
battery. Inspect
battery
cable con
nections
for
corrosion,
and clean
if
necessary.
Brush
the
cable connectors with grease
to
retard
further
corrosion,
then tighten the
connectors securely.
(2)
TEST CYLINDER COMPRESSION. Operate
the
engine until normal operating
temperature
is
reached.
Turn
the
ignition
switch off.
Remove
all spark plugs.
Set
the throttle to
wide open
position and
leave it
open
for
the
test.
Using
a compression
tester,
test the
compression
of each
cylinder.
Crank
the
engine
for
at
least four
com
pression strokes.
All
cylinders should
be
tested the
same
number of
strokes
to
assure accurate readings.
The
compression
of all cylinders should
be
uniform
within
10
pounds.
Record
the
compression of each cyl
inder.
A
reading
of
more
than
10
pounds
above normal
indi
cates carbon or
lead deposits in
the
cylinder.
A reading below
normal
indicates leakage
at
the rings,
valves, or
head
gasket.
(3) CLEAN, ADJUST,
AND INSTALL SPARK
PLUGS. Sandblast
the
spark
plugs,
wipe
the
porcelain
clean,
file
the
electrode
tips
flat,
and adjust
the
spark
gap.
Test
the
plugs
in
an approved
spark
plug
tester.
Replace
any
plugs
that
have broken
or chipped porcelain,
badly
burned
electrodes,
or
that
do
not check satisfac
torily on
the tester.
Install
the
spark plugs and
tighten
to
specifications.
(4)
CHECK AND ADJUST TIMING AND INSPECT
BREAKER POINTS. Disconnect
the
vacuum
line be
tween the
distributor
and carburetor.
Start
the
engine
and operate
it
at
idle
speed.
Check
the
timing
with a
timing
light
and make
the
necessary
adjustments.
Con
nect
the
distributor
vacuum
line
after
completing the
adjustments.
Inspect
the
distributor
points
for
pits,
exces
sive
metal
transfer,
and
burns. Replace
points which
cannot
be
cleaned
up
by
light
application of a point
file.
(5)
CHECK ENGINE VACUUM AND ADJUST
CARBURETOR IDLE. Check
the
engine manifold
vacuum at
idle
speed.
If
the
vacuum
is lower
than
specified,
check
for leakage
at
the
vacuum
lines
and
intake
manifold.
Check
the
carburetor
idle
adjustment.
If
the
vacuum
is
still
below
normal or
is
erratic,
it is
an
indication
of
bad
rings, sticky valves,
weak
valve
springs,
or
leaky
gaskets.
If
this
condition
exists,
it
should
be
reported
to the
customer.
Set
the
carburetor
idle
speed
to
specifications.
Set
the
idle fuel
adjustment
to
obtain
the
smoothest engine
idle
at
the
highest
manifold
vacuum and/or engine r.p.m.
Reset
the
idle
speed
if
required.