GMC 1976 ZEO 6083 User manual
X-7525
SECTION INDEX
General
Information,
Periodic
Maintenance
0
and
Lubrication
Body, Heating
and
1
Air
Conditioning
1975
AND
1976
Frame
MAINTENANCE
MANUAL
Front
Suspension
and
Final
Drive
3
MOTOR
HOME
Rear
Suspension
4
ZEO
6581
Brakes
5
Engine
6A
AND
Engine
6K
Cooling
System
TRANS
MODES
Engine
Fuel
System
6M
Emission
6T
ZEO
6083
Control
Systems
Engine
6Y
ZEO
6583
Electrical
Transmission
7
Fuel
Tank
8
and
Exhaust
Steering
System
9
0
MC
Wheels
and
Tires
10
Chassis
Electrical
12
TRUCK
&
COACH
DIVISION
Radiator
and
Coolant
13
GENERAL
MOTORS
CORPORATION
Recovery
System
RONTIAC,
MICHIGAN
48053
Bumpers
14
eneral
Motors
Corporation,
1975
Printed
in
U
.S .A
.
Miscellaneous
GMC
Living
Area
24
X-7525,
5M
Facilities
ALPHABETICAL
INDEX
WIRING
DIAGRAMS
SECTION
0
GENERAL
INFORMATION,
PERIODIC
MAINTENANCE,
AND
LUBRICATION
In
order
that
the vehicle
may
be
specifically
iden-
GENERAL
MOTORS
CORPORATION
WARRANTY
MAY
BE VOIDED
IF
WEIGHT
EXCEEDS
ANY
OF
RATINGS
SHOWN
.
GROSS
VEHICLE
WEIGHTINCLUDESWEIGHTOFBASE
VEHICLE,ALL
ADDEDEQUIPMENT,
DRIVER
AND
PASSENGERS,
AND
ALL
PROPERTY
LOADED
INTO
OR
ONTO
VEHICLE
.
RATINGS
IN
POUNDS
AS
MANUFACTURED
GROSS
VEHICLE
WEIGHT
FOR
THIS VEHICLE
MAXIMUM
FRONT
END
WEIGHT AT
GROUND
MAXIMUM
REAR
END
WEIGHT
ATGROUND
VEHICLE
IDENTIFICATION
NO
.
A-3688
Figure
1-Vehicle
Identification
Plate
VEHICLE
IDENTIFIC
ATION
GENERAL
INFORMATION
0- 1
Contents Of
This
Section
Are
Listed
Below
:
SUBJECT
PAGE
NO
.
Vehicle
Identification
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0-1
Component
Identification
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0-2
Hoisting
Instructions
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0-3
Jack
Usage
Instructions
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0-3
Towing
Vehicle
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.0-4
Engine,
Chassis,
and
Body
Maintenance
Schedule
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0-6
Explanation
of
Maintenance
Schedule
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0-7
Recommended
Fluids
and
Lubricants
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.0-11
Lubrication
Details
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0-12
Winterization
and
Vehicle Storage
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0-16
The
Vehicle
Identification
and
Weight
Rating
tified
as to
manufacturer,
engine
type,
year
of
manu-
Plate
(figure
1)
located
behind
the
right front access
facture,
etc
.,
refer
to
Figure
2
.
door
shows
the
"Vehicle
Identification
Number",
and
the
"As
Manufactured"Gross
Vehicle
Weight
Rating
for the vehicle to
which
it is
attached
.
(TYPICAL
IDENTIFICATION
NUMBER
TZE335V100053)
MODEL
DESIGNATION
Model
Code
Vehicle
Length
16
GMC
MotorHome
26'
33
TransMode
23'
36
TransMode
26'
MFD
.
B
Y
GMC
ENGINE
TYPE
E-VS
Gasoline
Figure
2-Vehicle
Identification
Number
r
0-
2
GENERAL
INFORMATION
COMPONENT
IDENTIFICATION
ENGINE
The
engines
are
identified
by
a
code
tape
installed
directly
above
the
engine
serial
number
which
is
stamped
on
the
engine
oil
fill
tube
(figure
3)
.
Figure
3-Engine
Identification
TRANSMISSION
The
transmission
model and
code
numbers
are
stamped
on
the
converter
housing
as
shown
in
Fig-
ure
4
.
FINAL
DRIVE
The
ratio
and
date
codes
-are
stamped
on
the
flange
near
the
right
hand
spreader
hole as
shown
in
Figure
5
.
Date
Code
:
The
code
letter
is
for
the
month
and
the
number(s)
are for actual
date
.
Ratio
Code
:
"T"
=
3
.07
:1
EXAMPLE
:
T
A12
=
3
.07
:1,
built
January
12
(J
=
9th
month,
I
is
not
used)
.
A
twin
post hoist
of
sufficient
capacity
and
with
proper
adapters
and/or
fittings
must
be
used
.
Front
hoisting position
is
the front
engine
cross-
member
.
HOISTING
INSTRUCTIONS
Figure
4-Transmission
Serial
Number
Plate
Figure
5-Final
Drive
Identification
Rear
hoisting
must
be
done
at
the rear
suspension
brackets
.
If
an
"I"
beam
type
adapter
is
used
it
should
be approximately 82
inches
in
length to gain
adequate
support
at
suspension
brackets
.
(figure
6)
If
vehicle
is
to
be
placed
on
jack
stands
for
maintenance
or
repairs,
the
hoisting
points
should
be
used
.
CAUTION
:
To
help
avoid
serious
damage
to
your
vehicle,
the
vehicle
should
be
raised
onlyon
twinpost
hoists
of
1
S,
000
pounds
or
more
total
rated
capacity,
at
the
suspension
points
noted
(see
diagram)
.
Before
raising,
check
overhead
clearance
to
see
that
it
is
sufficient
for the
vehicle
.
Do
NOT
use the
vehicle
jack
for
hoisting
or
maintenance
.
It
is
designed
for use
only
when
changing
tires
.
CAUTIONS
1
.
Follow
jacking
instructions
in
order
to
reduce
the
possibility
of
serious
personal
injury
.
2
.
The
jack
is
designed
for
use
only
when
chang-
ing
wheels
.
3
.
Never
get
beneath
the vehicle
when
using
jack
.
4
.
Do
not
start
or
run
engine
while
vehicle
is
on
jack
.
.
Figure
7-Jacking
at
Front
of
Vehicle
GENERAL
INFORMATION
0-
3
FRONT
ENGINE
REAR SUSPENSION
CROSSMEMBER
BRACKETS
DENOTES
APPROVED
LIFTING
POINTS
A-1941
Figure
6-Vehicle
Hoisting
Points
JACK
USAGE
INSTRUCTIONS
INSTRUCTIONS
Park on
level
surface
and
set
parking
brake
firmly
.
Set
transmission
in
"PARK"
.
Activate
Hazard
Warning
Flasher
.
Jack,
jack
chain,
handle,
"jacking
pad"
(wooden
block),
and
lug
wrench
are located
under
dinette
seat
.
Figure
8-Jacking
at
Rear
of
Vehicle
0-
4
GENERAL
INFORMATION
Block
both
front
and
rear
of
the
wheel
diagon-
ally
opposite
the
jack
position
.
Loosen
but
do
not
remove
wheel
nuts
.
JACKING
AT
FRONT-Place
hydraulic
jack
on
wood
block
near
energy absorbing
front
bumper
bracket
.
Place
hook
at
flange
of
front
cross-member
.
Pass
chain
under
bumper
and
adjust
chain
length
to
snug
fit
on
fork
on
top
of
jack
(See
figure
7)
.
JACKING
AT
REAR-Place
hydraulicjack
on
wood
block
close
to
rear
suspension
bracket
(See
figure
8)
.
The
hook
is
placed
in
the
drainage
slot
under
bracket
.
Adjust
chain
length so
link
will
fit
in
fork
at
top
of
jack
.
TOWING
AT
FRONT
TOWING
Proper
lifting
and
towing
equipment
is
necessary
to
prevent
damage
to the
vehicle
during
any
towing
operation
.
State (Provincial
in
Canada)
and
local
laws
applicable to
vehicles
to
tow
must
be
followed
.
No
towing
operation
should
be
attempted
which
would
jeopardize
the
safety
of
the
wrecker
operator,
any
bystanders
or
other
motorists
.
Passengers
should
never
ride in
a
towed
vehicle
for
any
reason
.
NOTE
:
Since
the
vehicle
could
exceed
the
lift
and
GVW
capacity of
most
sling
type
equip-
ment,
heavier
equipment
such
as
chains
and
spreader
bar
should
be
used
.
Also,
a
wrecker
with
at
least
8,000
lbs
.
capacity
shouldbeused
.
Vehicle
may
be
towed
on
all
six
wheels,
at
speeds
less
than 35
MPH,
for
distances
up
to
50
miles,
provided
the
final
drive,
axle,
transmission,
and
steering
system
are
otherwise
normally
operable
.
Use
only
towing
equipment
specifically
designed
for
this
purpose
following
the
instructions
of
the
towing
equipment
manufacturer
.
A
separate
safety
chain
system
must
be
used
.
For
suchtowing
the
steering
must
be
unlocked,
transmission
in
neutral
and
the
parking
brake
released
.
Attachments
must
be
to
en-
gine front
crossmember
.
Do
not
attach
to
bumpers
or
associated
brackets
.
Remember
that
power
brakes
and
power
steering
assists
will
not
be
available
when
engine
is
inoperative
.
When
towing
the
vehicle the
air
bellows
in
the
dle
.
TOWING
VEHICLE
Close
valve
at
base
of
jack
and
insert
jack han-
Always
operate
jack with
slow,
smooth
motion
.
Raise
vehicle so
tire
just
clears
surface,
replace
wheel
and
slightly
tighten
wheel
nuts
.
Open
valve
at
base
of
jack
to
lower,
then
fully
tighten
wheel
nuts
.
Proper
torque
is
250
foot
pounds
.
CAUTION
:
Use
lug
wrench
provided
to
tighten
wheel
nuts
securely
if
torque
wrench
is
not
available
.
(Follow
the
nut
tightening
sequence
shown
in
WHEELSAND
TIRES,
Section
10 of
this
manual
At
the
earliest
opportunity
have
wheel nut
torque
checked
.
This
is
necessary
to
help
prevent
loosening
or
stripping
of
the
wheel
nuts
.
rear
suspension
should be
inflated
to
maximum
capacity
and
then
place the
power
level
controls
in
"HOLD"
(vehicles
with
power
level
option)
.
On
vehicles
without
the
power
level
option,
disconnect
the
height control
valve
link
(figure
9)
on
each
side
of the vehicle
.
Raise
the
arm
on each
height
control
valve
to
inflate
the
air
bellows
to
provide
maximum
ground
clearance
for
the
vehicle
.
The
leveling
valve
can
then
be
released
to
the neutral
position
.
Tow
chains
should
be
attached
to
engine
front
crossmem-
her
(See
figure
10)
.
Note
that
a
six
inch
length
of
2"
x
4"
wood
block
must
be
placed
on
top
of
theengine
Figure
9-Disconnecting
Height
Control
Valve
Link
front
crossmember
on
the
left
side
.
The
chain
should
then
be
attached
around
both
the
wood
block
and
the
engine
front
crossmember
.
Care
should
be
taken
so
that
the
chain
does
not
contact
the
fuel line
on
the
engine
front
crossmember
.
Figure
1
1-Spacer
Block
Assembly
Figure
10-Towing
Vehicle
GENERAL
INFORMATION
0-
5
CAUTION
:
If
the
six
inch
length
wood
block
is
not
installed,
the
towing
chain
could
sever
the
fuel line
on
theengine
front
crossmem-
ber
.
A
wood
spacer
block
assembly
should
be
placed
under
the
front
crossmember
(See
figure
10) to
re-
lieve
some
of
the
load
from
the
energy
absorbers
and
bumper
.
This
spacer
block
assemblyshould
be
di-
mensioned,
constructed
of
hardwood,
and
bolted
together
with
three
thru-bolts
as
shown
in
Figure
11
.
Raising
front of
vehicle
so front
wheels
are
four
inches off
the
ground
will
provide
about
five-inch
ground
clearance
at
the
rear
when
towing
.
Separate
safety
chains should
be
attached
to
lower
control
arms
.
TOWING
ATREAR
It
is
not
recommended
that
vehicle
be
towed
with
the rear
raised
as
this
could
result in
suspension
or
crossmember
damage
.
ENGINE,
CHASSIS,
AND
BODY
MAINTENANCE
SCHEDULE
LUBE
AND
GENERAL
MAINTENANCE
0-
6
GENERAL
INFORMATION
SAFETY
MAINTENANCE
EMISSION
CONTROL
MAINTENANCE
(1974
CERTIFIED
ENGINE)*
WHEN
TO
PERFORM
SERVICES
(Months
or Miles,
Whichever
Occurs
First)
Item
No
.
SERVICES
(For
Details,
See
Numbered
Paragraphs)
Every 3
months
or
3,000
miles
1
Chassis
Lubrication
2
Engine
Oil
-
Change
Every 6
months
or
6,000
miles
3
Fluid
Levels
-
Check
4
Air
Conditioning
System
-
Check
5
Air
Compressor
Air
Filter
-
Clean
Every
6,000
miles
(Check
wheel
nut torque
after
1st
500
miles)
6
Tire
Rotation
At
1st
oil
change
and
then
every
2nd
7
Engine
Oil
Filter
-
Replace
Every 12
months
or
12,000
miles
8
Automatic
Transmission
.
and
Final
Drive
Lubricant
-
Change
9Cooling
System
-
See
Explanation
of
MaintenanceSchedule
Every
24,000
miles
10 Rear
Wheel
Bearings
-
Clean
&
Repack
11
Final
Drive
Boots
&
Output
Shaft
Seals
-
Check
Every
6
months
or
6,000
miles
12
Owner
Safety
Checks
13
Tires
and
Wheels
-
Inspection
14
Exhaust
System
-
Check
15
Engine
Drive
Belts
-
Check
16
Suspension
and
Steering
-
Check
17 Brake
and
Power
Steering
-
Check
Every 12
months
or
12,000
miles
18
Drum
Brakes
and
Parking
Brake
-
Check
19
Throttle
Linkage
-
Check
20
Underbody
-
Flush
and
Check
21
Bumper
-
Check
At
1st
6
months
or
6,000
miles
-
22
Thermostatically
Controlled
Air
Cleaner
then
at
12
months/
12,000
mile
23
Carburetor
Choke
intervals
24
Timing,
Dwell,
Carb
.
Idle,
Distributor
&
Coil
At
1st
6
months
or
6,000
miles
25
Carburetor
&
Intake
Manifold
Mounting
Every
6,000
miles
26
Spark
Plugs
(When
using
leaded
fuels)
Every
12
months
or
12,000
miles
27
Thermal
Vacuum
Switch
and
Hoses
28
Carburetor
Fuel
Filter
29
PCV
System
30
Air Cleaner
Element
31
Spark
Plugs
and
Ignition
Coil
Wires
Every
24
months
or
24,000
miles
32
Engine
Compression
33
ECS
System
34
Fuel
Cap
.
Tanks
and
Lines
EMISSION
CONTROL
MAINTENANCE
(1975
AND
1976
CERTIFIED
ENGINE)
*To
determine
year engine
was
certified,
refer
to
emission
control
decal
on
engine
valve
cover
.
EXPLANATION
OF
MAINTENANCE
SCHEDULE
Presented
below
is
a
brief
explanation
of
each
of
the
services
listed
in
the
preceding
Maintenance
Schedule
.
Vehicle
operation
under
conditions
such
as
heavy
dust,
continuous
short
trips,
use
of
other
than
un-
leaded
or
low
lead
fuels
or pulling
trailers,
is
not
considered
normal
use
and
therefore
more
frequent
maintenance
will
be
required
.
Such
additional
maintenance
requirements
are
included
where
appli-
cable
.
ITEM
NO
.
SERVICES
LUBE
AND
GENERAL
MAINTENANCE
1
CHASSIS-Lubricate
all
grease
fittings
in
front
and
rear
suspension
and
steering
linkage
.
Also
lubri-
cate
transmission
shift
linkage,
brake
pedal
spring,
parking
brake
cable
guides
and
linkage
.
2
ENGINE
OIL-Change
each
3
months
or
3,000
miles,
whichever
occurs
first
.
3
FLUID
LEVELS-Check
level
of
fluid
in
brake
master
cylinder,
power
steering
pump,
all
batteries,
engine,
final
drive,
transmission,
and
windshield
washer
.
The
engine
coolant
should
be
checked
for
proper
level
and
freeze
protection
to at
least
-20°F
.
(-29°C
.)
(-37°C
.
in
Canada),
or
to the
lowest
tempera-
ture
expected
during
the
period
of vehicle
operation
.
Proper
engine
coolant
also
provides corrosion
pro-
tection
.
Any
significant
fluid
loss in
any
of
these
systems
GENERAL
INFORMATION
0-
7
or
units
could
mean
that
a
malfunction
is
developing
and
corrective
action
should
be
taken
immediately
.
A
low
fluid
level
in
the
brake
master
cylinder front
reservoir
could
also
be an
indicator
that
the
disc
brake
padsneed
replacing
.
4
AIR
CONDITIONING-Check
condition
of
air
con-
ditioning
system
hoses
and
refrigerant
charge
at
sight glass
.
Replace
hoses
and/or
refrigerant
if
need
is
indicated
.
5
AIR
COMPRESSOR-Filter
should
be
washed
with
soap
and
water
solution
or
replaced
.
6
TIRES-To
equalize
wear,
rotate
tires
as
illus-
trated
in
Section
10
and
adjust
tire
pressures
as
shown
on
tire
placard
on
glove
box
door
.
Have
wheel-nuttorque
checked
after
1
st
500
miles
and
500
miles
after
every
wheel
replacement
thereafter
.
7
ENGINE
OIL
FILTER-Replace
at
the
first
oil
change
and
every
2nd
oil
change
thereafter
.
8
AUTOMATIC
TRANSMISSION
FLUID
AND
FINAL
DRIVE
LUBRICANT-Change
the
transmission
fluid
and
filter
;
change
final
drive
lubricant
.
9
COOLING
SYSTEM-At
12-month
or
12,000-mile
intervals,
wash
radiator
cap
and
filler
neck with
clean
water,
pressure
test
system
and
radiator
cap
for
proper
pressure
holding
capacity
.
(Tighten
hose
clamps
and
inspect
condition
of
all
cooling
and
heater
hoses
.)
Replace
hosesevery
24
months
or
24,-
000
miles or
earlier
if
checked,
swollen
or
otherwise
deteriorated
.
At
1st
6
months
or
6,000
miles
-
then
at
12
months/12,000
mile
35
Thermostatically
Controlled
Air
Cleaner
-
Check
intervals
36
Carburetor
Choke
-
Check
37
Engine
Idle
Speed and
Mixture
Adjustment
38
Carburetor
and
Intake
Manifold
Mounting Torque
Every 6,000
miles
39
Spark
Plug
Replacement
Every
12
months
or
12,000
miles
40
Carburetor
Fuel
Filter
Replacement
41
Thermal
Vacuum
Switch
and
Hoses
-
Check
42
PCV
System
-
Check
43
Air
Cleaner
Element
Replacement
44
Spark
Plug
Wires
-
Check
45
Engine
Timing
Adjustment
and
Distributor
-
Check
46
Throttle
Return
Control
-
Check
Every
24
months
or
24,000
miles
47
ECS
System
Check
and
Filter
Replacement
48
Fuel
Cap,
Tanks and
Lines
-
Check
0-
8
GENERAL
INFORMATION
Also
each
12
months
or
12,000
miles,
clean
ex-
terior
of
radiator
core
and
air
conditioning
con-
denser
.
Every
24 months
or
24,000
miles, drain,
flush,
and
refill
the
cooling
system
with
a
new
coo-
lant
solution
.
10
REAR
WHEEL
BEARINGS-Clean
and
repack
rear
wheel
bearings
with
a
lubricant
as
specified
in
the
"Recommended
Fluids
and
Lubricants"
chart
.
CAUTION
:
"Long
fiber"
or
"viscous"
type
greases
should not
be
used
.
Do
not
mix
wheel
bearing
lubricants
.
Be
sure
to
thoroughly
clean
bearings
and
hubs
of
all
old
lubricant
before
replacing
.
11
FINAL
DRIVE
AXLE
BOOTS
AND
OUTPUT
SHAFT
SEALS-Check
for
damaged,
torn or
leaking
boots
on
drive
axles
and
for
leaking
output
shaft
seal
.
Replace
defective
parts
as
necessary
.
SAFETY
MAINTENANCE
12
OWNER
SAFETY
CHECKS-The
maintenance
schedule
folder
in
the
glove
box
lists
several
items
the
owner
should
check and have
repaired
if
not
correct
.
13
TIRES
AND
WHEELS-To
equalize
wear,
rotate
tires
as
illustrated
in
Section
10
.
Adjust
tire
pressures
as
recommended
on
tire
placard
on
glove
box
door
.
Check
disc
brake
pads
and
condition
of
rotors
while
wheels
are
removed
.
Check
tires
for
excessive
wear
or
damage
.
Make
certain
wheels
are
not
bent
or
cracked
and
wheel
nuts
are
tight
.
Check
tire
inflation
pressure
at
least
monthly,
or
more
often
if
daily
visual
inspection
indicates the
need
.
14
EXHAUST
SYSTEM-Check
complete
exhaust
system
and
nearby
body
areas
of
vehicle
engine
and
motor-generator
system
for
broken,
damaged,
miss
ing
or
mispositioned
parts,
open
seams,
holes,
loose
connections
or
other
deterioration
which
could
per-
mit
exhaust
fumes
to
seep
into
the
passenger
com-
partment
.
Dust
or
water
in
the
passenger
compartment
may
be an
indication
of
a
problem
in
one
of
these areas
.
Any
defects
should be
corrected
immediately
.
To
help
ensure
continued
integrity,
ex-
haust
system
pipes
rearward
of
the
muffler
must
be
replaced whenever
a
new
muffler
is
installed
.
15
ENGINE
DRIVE
BELTS-Check
belts
driving
fan,
Delcotron,
power
steering
pump
and
air
condition-
ing
compressor
for
cracks,
fraying,
wear
and
tension
.
Adjust
or
replace
as
necessary
.
It is
recommended
that
belts
be
replaced every
24
months
or
24,000
miles,
whichever
occurs
first
.
16
SUSPENSION
AND
STEERING-Check
for
da-
maged,
loose
or
missing
parts,
or
parts
showing
visi-
ble
signs
of
excessive
wear
or lack
of
lubrication
in
front
and
rear
suspension
and
steering
system
.
Ques-
tionable
parts
noted should
be
replaced
by a
qualified
mechanic
without
delay
.
17
BRAKES
AND
POWER
STEERING-Check
lines
and
hoses
for
proper attachment,
leaks,
cracks,
chaf-
ing,
deterioration,
etc
.
Any
questionable
parts
noted
should
be
replaced
or repaired
immediately
.
When
abrasion
or
wear
is
evident
on
lines
or
hoses,
the
cause
must
be
corrected
.
18
DRUM
BRAKES
AND
PARKING
BRAKE-Check
drum
brake
linings
and
other
internal
brake
compo-
nents
at
each wheel
(drums,
wheel
cylinders,
etc
.)
.
Parking brake
adjustment
also
should be
checked
whenever
drum
brake
linings
are
checked
.
NOTE
:
More
frequent
checks
should
be
made
if
driving
conditions
and
habits
result in
frequent
brake
application
.
19
THROTTLELINKAGE-Check
for
damaged
or
missing
parts,
interference
or
binding
.
Any
deficien-
cies
should
be
corrected
without
delay
.
20
UNDERBODY-In
geographic
areas
using
a
heavy
concentration
of road
salt
or
other
corrosive
materials
for
snow
removal
or
road
dust
control,
flush
and
inspect
the
complete under
side
of
the
vehicle
at
least
once each
year,
preferably
after a
winter's
exposure
.
Particular
attention
should
be
given
to
cleaning
out
underbody
members
where
dirt
and
other
foreigh materials
may
have
collected
.
21
BUMPERS-Check
the
front
and
rear
bumper
systems
at
12-month/
12,000-mile
intervals
to
be
sure
the
impact
protection
and
clearance
originally
de
signed
into
the
system remains
in a
state
of
full
readi-
ness
.
They
also
should
be
checked
whenever
there
is
obvious
bumper
misalignment,
or
whenever
the
vehi-
cle
has
been
involved
in
a
significant
collision in
which
the
bumper
was
struck,
even
when
no
damage
to
the
bumper
system can be
seen
.
EMISSION
CONTROL
MAINTENANCE
(1974
CERTIFIED
ENGINE)
22
THERMOSTATICALLY
CONTROLLED
AIR
CLEANER-Inspect
installation
to
make
certain that
all
hoses
and
ducts
are
connected
and
correctly
in-
stalled
.
Also
check
valve
for
proper
operation
.
23
CARBURETOR
CHOKE-Check
choke mech-
anism
for
free
operation
.
Any
binding
condition
which
may
have
developed
due
to
petroleum
gum
formation
on
the
choke
shaft or
from
damage
should
be
corrected
.
24
TIMING,
DWELL,
CARBURETOR
IDLE,
DISTRIBU-
TOR
AND
COIL-Adjust
ignition
timing,
dwell
and
carburetor
idle
speed
accurately
(following the
specifications
shown
on
the
label
attached
to
engine
rocker
cover)
at
the
first
6
months
or
6,000
miles of
operation
then
at 12
month
or
12,000
miles
.
Then
at
12
month
or
12,000
mile
intervals
.
Adjustment
must
be
made
with
test
equipment
known
to be
accurate
.
Replace
distributor
points
every
12
months
or
12,000
miles
and
replace
cam
lubricator
every
24
months
or
24,000
miles
.
In
addition,
carefully
in
spect the
interior
and
exterior
of the
distributor
cap,
distributor
rotor
and
coil
for
cracks,
carbon
tracking,
and
terminalcorrosion
.
Clean
or replace
as
necessary
at
24-month/24,000
mile
intervals
to
prevent
misfir-
ing
and/or
deterioration
.
Proper
functioning
of
the
carburetor
is
particu-
larly
essential
to control of
emissions
.
Correct
mix-
tures
for
emission
compliance
and
idle
quality
have
been
preset
by
GMC
Truck
.
Plastic
idle
mixture
li-
miters
havebeen
installed
on
the
idle
mixture
screws
to
discourage
unauthorized
adjustment
.
These
idle
limiters
are
not
to
be
removed
unless
some
major
carburetor
repair
or
replacement
which
affects
the
idle
screw
adjustment
has
been
necessary
.
At
12
months
or
12,000
mile
intervals
or
in
case
of
major
carburetor
overhaul,
or
when
poor
idle
quality
exists,
the
idle
mixture
should
be adjusted
by
use of
a
CO
meter
when
an
accurate
meter
is
availa-
ble,
or
the
alternate
mechanical
method
should
be
used
to adjust
idle
mixture
(See
SECTION
6M)
.
25
CARBURETOR
AND
INTAKE
MANIFOLD
MOUNTING-Torque
carburetor and
intake
manifold
attach-
ing
bolts
and/or
nuts
at
first
6
months
or
6,000
miles
of
vehicle
operation
.
26
SPARK
PLUGS-Replace
at
6,000
mile
intervals
when
operatingwith
leaded
fuels,
or
at
12,000-mile
intervals
when
using
unleaded
fuels
.
Use
of
leaded
fuels
results
in
lead
deposits
on
spark
plugs
and
can
cause
misfiring
at
mileages
less
than
12,000
miles
.
Where
misfiring
occurs
prior
to
6,000
miles,
spark
plugs
in
good
condition
can
often be
cleaned,
tested,
and
reinstalled
in
an
engine
with
acceptable
results
.
27
THERMAL
VACUUM
SWITCH
AND
HOSES-
Check
for
proper
operation
.
A
malfunctioning
switch
must
be
replaced
.
Check
hoses
for
proper
connection,
cracking,
abrasion
or
deterioration
and
replace as
necessary
.
GENERAL
INFORMATION
0-
9
28
CARBURETOR
FUEL
FILTER-Replace
filter at
12-month/12,000-mile
intervals
or
more
frequently
if
clogged
.
29
POSITIVE
CRANKCASE
VENTILATION
SYSTEM
(PCV)-Check
system
for
satisfactory
operation
at
12-
month
or
12,000-mile
intervals
using
a
tester,
and
clean
filter
.
Replace
the
PCV
valve
at
24-month
or
24,000-mile
intervals
and
blow
out
PCV
valve
hose
with
compressed
air
.
The
PCV
valve
should
be
re-
placed
at
12-month
or
12,000-mile
intervals
when
the
vehicle
is
used
in
operations involving
heavy
dust,
extensive
idling,
trailer
pulling,
and
short
trip
use
at
freezing
temperatures
where
engine
does
not
become
thoroughly
warmed-up
.
30
AIR
CLEANERELEMENT-Replace
the
engine
air
cleaner
element
under
normal
operating
conditions
every
12,000
miles
.
Operation
of
vehicle
in
dusty
areas
will
necessitate
more
frequent
element
replace-
ment
.
CAUTION
:
Do
not
operate
the engine
with-
out the
air
cleaner
unless
temporary
re-
moval
is
necessary
during
repair
or
maintenance
of
the
vehicle
.
When
the air
cleaner
is
removed
backfiring
can
cause
fire
in
the engine
compartment
.
31
SPARK
PLUG
AND
IGNITION
COIL
WIRES-In-
spect
spark
plug
and
ignition
coil
wires
for
evidence
ofchecking
or
cracking
of
exterior insulation
and
tight
fit
in
the
distributor
cap
and
at
the
spark
plugs
.
Exterior
of
wires
should
be
cleaned,
any
evidence
of
corrosion
on
ends
removed
and
wire replaced
if
deteriorated
.
32
ENGINE
COMPRESSION-Test
engine
cranking
compression
.
If
a
problem
exists,
have
correction
made
.
Minimum
compression
recorded
in
any one
cylinder
should
not
be
less
than
70%
of
the
highest
cylinder
.
For
example,
if
the
highest
pressure
in
any
one
cylinder
is
1501bs
.,
the
lowest
allowable
pressure
for
any
other
cylinder
would
be
105
lbs
.
(150
X
70%
=
105)
.
33
EVAPORATION
CONTROL
SYSTEM
(ECS)-Check
all
fuel
and
vapor
lines
and
hoses
for
proper
connec-
tions
and
correct
routing
as well as
condition
.
Remove
canister(s)
and
check
for
cracks
or
damage
.
Replace
damaged
or deteriorated parts
as
necessary
.
Replace
filter
in
lower
section of
canister
.
If
vehicle
is
equipped
with
two
canisters,
filter is
located
in
the
lower
canister
only
.
34 FUEL
CAP, FUEL
LINES
AND
FUEL
TANKS-In-
spect the
fuel
tank
cap
and
lines
for
damage
which
could
cause
leakage
.
Inspect
fuel
cap
for
correct
seal
ing
ability
and
indications
of physical
damage
.
Re-
place
any
damaged
or
malfunctioning
parts
.
0-
1
0
GENERAL
INFORMATION
EMISSION
CONTROL
MAINTENANCE
(1975
-
1976
CERTIFIED
ENGINE)
35
THERMOSTATICALLY
CONTROLLED
AIR
CLEANER-Inspect
installation
to
make
certain
that
all
hoses
and
ducts
are
connected
and
correctly
in-
stalled
.
Also
cheek
valve
for
proper
operation
.
36
CARBURETOR
CHOKE
AND
HOSES-Check
choke
mechanism
for
free
operation
.
Any
binding
condition
which
may
have
developed
due
to
pe
troleum
gum
formation
on
the
choke
shaft or
from
damage
should
be
corrected
.
Check
carburetor
choke
hoses
for
proper
connection,
cracking, abra-
sion
or
deterioration
and
correct or
replace
as
neces-
sary
.
37
ENGINE
IDLE
SPEED
AND
MIXTURE-Adjust
en-
gine
idle
speed
accurately
(following
the
specifica-
tions
shown
on
the
label
attached
to
the
engine
rocker
cover)
at
the
first
6months
or
6,000
miles
of
operation,
then
at 12
month
or
12,000
mile
intervals
.
Adjustment
must
be
made
with
test
equipment
known
to
be
accurate
.
At
12
month
or
12,000
mile
intervals
or
in
case
of
major
carburetor
overhaul,
or
when
poor
idle
quality
exists,
the
idle
mixture
should
be
adjusted
by
use
of
a
CO
meter
when
an
accurate
meter
is
availa-
ble,
or
the
alternate
mechanical
method
(lean
drop)
should
be
used
to adjust the
idle
mixture
.
(See Sec-
tion
6M)
.
38
CARBURETOR
AND
INTAKE
MANIFOLD
MOUNT-
ING-Torque
carburetor
and
intake
manifold
attach-
ing
bolts
and/or
nuts
at
first
6
months
or
6,000
miles
-then
at
12
month/
12,000
mile
intervals
.
39
SPARK
PLUGS-Replace
at
6,000
mile
intervals
when
operatingwith
leaded
fuels,
or
at
12,000-mile
intervals
when
using
unleaded
fuels
.
Use
of
leaded
fuels
results
in
lead
deposits
on
spark
plugs
and
can
cause
misfiring
at
mileages
less
than
12,000
miles
.
Where
misfiring
occurs
prior to
6,000
miles,
spark
plugs
in
good
condition
can
often
be
cleaned,
tested,
and
reinstalled
in
an
engine
with
acceptable
results
.
40
CARBURETOR
FUEL
FILTER-Replace
filter
at
12-month
12,000-mile
intervals
or
more
frequently
if
clogged
.
41
THERMAL
VACUUM
SWITCH
AND
HOSES-
Check
for
proper
operation
.
A
malfunctioning
switch
must
be
replaced
.
Check
hoses
for
proper
connection,
cracking,
abrasion
or
deterioration
and
replace as
necessary
.
42
POSITIVE
CRANKCASE
VENTILATION
SYSTEM
(PCV}-Check
the
PCV
system
for
satisfactory
operat-
ion
at
12,000-mile
intervals,
and
clean
filter
(located
in
rocker cover)
.
Replace
the
PCV
valve
at
24,000-
mile
intervals
and
blow
out
PCV
valve
hose
with
compressed
air
.
Replace
deteriorated
hoses
.
43
AIR
CLEANER
ELEMENT-Replace
the
engine
air
cleaner
element
under
normal
operating
conditions
every
12,000
miles
.
Operation
of vehicle
in
dusty
areas
will
necessitate
more
frequent
element
replace-
ment
.
Your
GMC
MotorHome
dealer
can
be
of
as-
sistance
in
determining
the
proper
replacement
frequency
for
the
conditions
under
which
you
oper-
ate
your
vehicle
.
CAUTION
:
DO
not
operate
the
engine
without
the
air
cleaner
unless
temporary
removal
is
necessary
during
repair
or
maintenance
of
the
vehicle
.
When
the
air
cleaner
is
removed
back-firing
can cause
fire
in
the
engine
compart-
ment
.
44
SPARK
PLUG
WIRES-Clean
exterior
of wires
;
remove
any
evidence
of
corrosion
on
end
terminals
.
Inspect
spark
plug
wires
for
evidence
of
checking,
burning, or
cracking
of
exterior
insulation
and
tight
fit
at
distributor
cap
and
spark
plugs
or
other
deterio-
ration
.
If
corrosion
cannot
be
removed
or
other
con-
ditions
above
are noted,
replace
wire
.
45
TIMING
AND
DISTRIBUTOR
CAP-Adjust
igni-
tion
timing
following
the
specification
on
label
at-
tached
to
the engine
rocker
cover
.
Also,
carefully
inspect
the
interior
and
exterior
of
the
distributor
cap
and
rotor
for
cracks,
carbon
tracking
and
terminal corrosion
.
Clean
or
replace
as
necessary
.
46
THROTTLERETURN
CONTROL
(TRC)-(California
Vehicles)
Check
hoses
for cracking,
abrasion
or
deterioration
and
replace as
necessary
.
Check
system
for
proper
operation
.
47
EVAPORATION
CONTROL
SYSTEM
(EM-Check
all
fuel
and
vapor
lines
and
hoses
for
proper
connec-
tions
and
correct
routing
as well
as
condition
.
Remove
canister(s)
and
check
for
cracks
or
damage
.
Replace
damaged
or deteriorated
parts
as
necessary
.
Replace
filter
in
lower
section
of
canister
.
If
vehicle
is
equipped
with
two
canisters,
filter
is
located
in
the
lower
canister
only
.
48 FUEL
CAP,
FUEL
LINES
AND
FUEL
TANKS-In-
spect
the
fuel
tank
cap
and
lines
for
damage
which
couldcause
leakage
.
Inspect
fuel
cap
for
correct
seal
ing
ability
and
indications
of
physical
damage
.
Re-
place
any
damaged
or
malfunctioning
parts
.
GENERAL
INFORMATION
0-
1 1
RECOMMENDED
FLUIDS
AND
LUBRICANTS
NOTE
:
Fluids
and
lubricants
identified
with
GM
part
numbers
or
GM
specifica-
tion
numbers
may
be
obtained
from your
GMC
Motor
Home
Service
Outlet
.
12
qts
.
after
complete
overhaul
.
USAGE
FLUID/LUBRICANT
CAPACITIES
Engine
oil
High
quality
SE
oil
5
qts
.
(6
w/filter)
Power
steering
system
and
GM
power
steering
fluid
Part
No
.
1
1/2
Qts
.
pump
reservoir
.
Includes
1050017
-
if
not
available
use
windshield
wiper
DEXRON II
automatic
motor
transmission
fluid
Final drive
SAE80W
or
SAE
80W-90
GL-5
gear
4
Pts
.
lubricant
(SAE
80W
GL-5
in
Canada)
Brake
system
and
master
cylinder
Delco
Supreme
11
or,
DOT-3
fluid
or
equivalent
Transmission
shift
linkage
Engine
oil
Chassis
lubrication
Chassis
grease
meeting
requirements
of
GM
6031-M
Transmission
DEXRON
®
I I
automatic
transmission
4 Qts
.
fluid
Parking
brake
cables
Chassis
grease
Front
wheel
bearings
High-melting
point
lubricant
Part
No
.
1051344
Rear
wheel
bearings
Chassis
grease
meeting
requirements
of
GM
6031-M
Body
door
hinge
pins,
hinges
and
Engine
oil
latches
at
the
front
access
doors,
external
utilities,
generator/storage
and
LP
gas
doors
.
Gas
fill
door
hinge
Windshield
washer
solvent
GM
Optikleen
washer
solvent
Part
No
.
1050001
or
equivalent
Energizers
(Batteries)
Colorless, odorless,
drinking
water
Engine
coolant
Mixture
of
water
and
a
high
quality
21 Qts
.
Ethylene
Clycol
base
type
anti-freeze
conforming
to
GM
Spec
.
1899-M
0-
1
2
GENERAL
INFORMATION
ENGINE
OIL
AND
FILTER
RECOMMENDATIONS
Use
only
SE
engine
oil
.
LUBRICATION
DETAILS
ENGINE
Refer
to
"Engine,
Chassis
and
Body
Mainte-
nance
Schedule"
for
oil
change
and
filter
replace-
ment
intervals
.
The
recommendations
in
the
"Engine,
Chassis
and
Body
Maintenance
Schedule"
apply
to
the
first
change
as well as
subsequent
oil
changes
.
The
oil
change
interval
for
the
vehicle's
engine
is
based
on
the use
of
SE
oils
and
quality
oil
filters
.
Oil
change
intervals
longer
than
those
listed
above
will
seriously
reduce
engine
life
and
may
affect
GMC
Truck
Coach's
obligation
under
the provisions
of
the
New
Vehicle
Warranty
.
A
high
quality
SE
oil
was
installed
in
the
engine
at
the
factory
.
It
is
not
necessary
to
change
this
factory-installed
oil
prior
to
the
recommended
nor
mal
change
period
.
However,
check
the
oil
level
more
frequently
during
the break-in
period
since
higher
oil
consumption
is
normal
until
the
piston
rings
become
seated
.
Figure
12-Engine
Oil
Viscosity
Chart
NOTE
:
Non-detergent
and
other
low
quality
oils
are
specifically
not
recommended
.
Only
the
use
of
SE
engine
oils
and
proper
oil
and
filter
change
intervals
assure
of
continued
proper
lubrication
of
the
vehicle's
engine
.
RECOMMENDED
SAE
VISCOSITY
(FIGURE
12)
Single
grade
oils
are
preferred,
however,
multi-
grades
such
as
SAE
1OW-30
or
1OW-40
are
also
acceptable
.
SAE
5W-20
oils
arenot
recommended
for
sus-
tained
high
speed
driving
.
SAE
5W-30
oils
(if
available)
may
be
used
if
extreme
low
temperatures
are
anticipated
.
SUPPLEMENTAL
ENGINE
OIL
ADDITIVES
The
regular
use
of
supplemental
additives
is
specifically
not
recommended
and
will
increase oper-
ating
costs
.
However,
supplemental
additives
are
available
that
can
effectively
and
economically
solve
certain
specific
problems
without
causing
other
dif-
ficulties
.
For
example,
if
higher
detergency
is
re-
quired
to
reduce
varnish
and
sludge
deposits
resulting
from
some
unusual
operational
difficulty,
a
thoroughly
tested
and
approved
additive-"Super
Engine
Oil
Supplement"-is
available
at
your
GMC
Motor
Home
service
outlet
.
Figure
13-Removing
Engine
Oil
Dipstick
CHECKING
OIL
LEVEL
The
engine
oil
should be maintained
at
the
proper
level
.
The
best
time
to
check
it
is
before
operating
the
engine
or
as
the
last
step
in
a
fuel
stop
.
This
will
allow
the
normal
oil
accumulation
in
the engine
to
drain
back
into
the
crankcase
.
To
check
the
level,
remove
the
oil
level
dipstick
located
inside
the
left
front ac-
cess
door
(See
figure 13)
wipe
it
clean
and
reinsert
it
fully
for
accurate
reading
.
The
oil
level
dipstick
is
marked
"FULL"
and
"ADD
."
(figure
14)
The
oil
level
should
be
maintained
within
the
margin,
nei-
ther
going
above
the
"FULL"
line
nor
below
the
"ADD"
line
.
Reseat
the
dipstick
firmly
after
taking
the
reading
.
One
(1)
quart
will
raise
the
oil
level
from
"ADD"
to
"FULL
."
NOTE
:
The
oil
dipstick
is
also
marked
"USE
SE
ENGINE
OIL,"
as
a
reminder
to
use
only
SE
oils
.
TRANSMISSION
The
transmission
dipstick
and
fill
tube
is
located
under
the
engine
access
cover
on
the
left
side
of the
engine
.
(figure
15)
Use
only
automatic
transmission
fluids
identified
with
the
mark
DEXRON II.
These
fluids
have
been
specially
formulated
and
tested
for
use
in
the
automatic
transmission,
and
are
available
from
the
GMC
Motor
Home
service
outlet
or
local
service
station
.
Check
the
fluid level
at
each
engine
oil
change
period
.
To make
an
accurate
fluid
level
check
:
1
.
Drive
vehicle several
miles,
making
frequent
starts
and
stops,
to
bring
transmission
up
to
normal
Figure
14-Engine
01
1
Dipstick
GENERAL
INFORMATION
0-
13
Figure
15-Removing
Transmission
Dipstick
operating
temperature
(approx
.
190-200°F
.)
(87
.8°C
.-93
.3°C
.)
.
2
.
Park
MotorHome
on a
level
surface
.
3
.
Apply
parking
brake
.
4
.
Place
selector
lever
in
"PARK"
and
leave en-
gine
running
.
5
.
Open
all
but
the
two
rear
windows,
then
remove
engine
cover
.
6
.
Remove
dipstick
and
wipe
clean
.
7
.
Reinsert
dipstick
until
cap
seats
.
8
.
Remove
dipstick
and
note
reading
.
(figure
16)
If
fluid
level
is
at
or
below
the
"ADD"
mark,
add
sufficient
fluid
to
raise
the
level
to
the
"FULL"
mark
.
One
pint
raises
the
level
from
"ADD"
to
"FULL
."
Do
not
overfill
.
Refer
to
the
Maintenance
Chart
for
servicing
schedule
.
Figure
16-Transmission
Dipstick
0-
1
4
GENERAL
INFORMATION
Figure
17-Replacing
Transmission
Oil
Filter
TRANSMISSION
OIL
FILTER
REPLACEMENT
(FIGURE
17)
NOTE
:
Have
a
drain
pan
ready
as
lubricant
will
begin
to
drain
as
bolts
are
loosened
.
1
.
Remove
(13)
bottom
pan
attaching
screws
.
2
.
Remove
bottom
panand
discard gasket
.
3
.
Remove
and
discard
oil
filter
assembly
.
4
.
Install
new
O-ring
seal
on
new
filter
and
intake
pipe
and
filter
assembly
and
install
.
5
.
Using
a
new
pan
gasket,
install
pan
.
Torque
attaching
screws
to 12
foot-pounds
.
6
.
Add
four
(4)
quarts of
DEXRON
®
II
auto-
matic
transmission
fluid
and
check
fluid
as
noted
above
.
Figure
18-Final
Drive
Cover
Removed
FINALDRIVE
(FIGURE
18)
FINALDRIVE
LUBRICANT
REPLACEMENT
1
.
Remove
(10)
cover
attaching
bolts
.
Have
a
drain
pan
ready
as
lubricant
will
begin
to
drain
as
bolts
are
loosened
.
2
.
Remove
cover
and
allow
lubricant
to
drain
.
Discard
old gasket
.
3
.
Using
a
new
cover
gasket,
install
cover
.
Torque
attaching
bolts
to
24
foot-pounds
.
Shield
to
be
bent
over
breather
hole
.
4
.
Add
four
pints
of
recommended
lubricant
through
fill
plug
hole
or
fill
until
lubricant
level
is
at
the
plug hole
.
STEERING
SYSTEM
POWER
STEERING
SYSTEM
(FIGURE
19)
Check
the
fluid
level
in
the
power
steering
pump
reservoir
at
each
oil
change
period
.
This
requires
the
removal
of the
engine
access
cover
.
The
reservoir
is
located
near
the
Delcotron
.
Add
GM
Power
Steering
Fluid
(if
GM
Power
Steering
Fluid
is
not
available,
DEXRON®II
Automatic
Transmission
Fluid
may
be
used)
as
necessary
to
bring
level
into
proper
range
on
the
filler
cap
indicator
depending
on
fluid
temper-
ature
.
If at
operating
temperature
(approx
.
150°F
.
65
.6
1
C
.)
hot
to the
touch)
fluid
should
be
between
"HOT"
and
"COLD"
marks
.
If
at
room
tempera-
Figure
19-Checking
Power
Steering
Fluid
Level
REAR
SUSPENSION
(2
FITTINGS
RIGHT
AND
LEFT)
SIDE
OF
VEHICLE
DRAG
LINK
ASSY
.
(2
FITTINGS)
L
.H
.
TIE
ROD
(2
FITTINGS)
FRONT
SUSPENSION
UPPER
AND
LOWER
BALL
JOINTS
(2
FITTINGS
RIGHT
AND
LEFT
SIDE
OF
VEHICLE
R
.H
.
TIE
ROD
(2
FITTINGS)
STEERING
COLUMN
TO
GEAR
SHAFT
ASSY
.
(2
FITTINGS)
STEERING
RELAY
LEVER
(1
FITTING)
A-1953
0-
16
GENERAL
INFORMATION
ture
(approx
.
70
*F
.
(21
.1
C)
fluid
should
be
between
`ADD"
and
"COLD"
marks
.
The
fluid
does not
require
periodic
changing
.
STEERING
LINKAGE
(FIGURE
20)
The
steering
linkage
(tie
rods)
and
suspension
should
be
lubricated,
using
a
water
resistant
E
.P
.
Chassis
Lubricant
that
meets
GM
Specification
6031-M,
at
every
oil
change
.
Seals
should
be
checked
for
damage
.
BRAKE
SYSTEM
BRAKE
MASTER
CYLINDER
(FIGURE
21)
The
master
cylinder
is
located
behind
the
left-
side
access
door
on
the front of
the
vehicle
.
The
fluid
level
in
the
master
cylinder
should
be
checked
at
each
oil
change
.
Wipe
off
the
brake
cylinder
filler
cap
and
unsnap
the
retainer
.
A
low
fluid level
in
the
front
brake
master
cylinder
reservoir
could
bean
indicator
that the
disc
brake
pads need
replacing
.
The
fluid
level
must
be maintained
at
1/4-inch
below
the
top
of
each
reservoir
with
Delco
Supreme
No
.
11
or
DOT-3
Brake
Fluid
or
equivalent
.
When
replacing
the
cap
be
sure to
fasten
the
retainer
securely,
taking
care
not
to
let
dirt
enter
the
reservoirs
.
Figure
21-Checking
Brake
Master
Cylinder
BLEEDING
BRAKES
The
need
for
bleeding
brakes
is
generally
in-
dicated
by
springy,
spongy
pedal
action
.
Pressure
bleeding
equipment
must
be
used
and
a
definite
bleeding
sequence
and
procedure
must
be
followed
.
For
proper
bleeding
sequence
see
BRAKES
(SEC-
TION
5)
of
this
manual
.
WINTERIZATION
AND
VEHICLE
STORAGE
Winterization
and
vehicle
storage
are
essential
service
functions
which
must
be
performed
on
GMC
Motor
Homes
.
Details
on
theseitems
are
covered
in
SECTION
24A
"Periodic
Maintenance
and
Lubrication"
SECTION
1
BODY,
HEATING
AND
AIR
CONDITIONING
This
section
includes
the
following
:
SUBJECT
PAGE
N0
.
Body
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1-1
Air
Conditioning
System
(Includes
Heating)
. .
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1-29
Heating
System
(Without
Air
Conditioning)
.
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1-106
BODY
BODY
1-1
Contents
of
this
section are
listed
below
:
SUBJECT
PAGE N0
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Key
Information
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Exterior
Maintenance
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1-2
Interior
Maintenance
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1-2
Dust
and
Water
Leaks
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Painting
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1-4
Glass
.
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1-5
Windshield
Wiper
System
.
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1-14
Entrance
Door
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1-17
Access
Doors
......
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1-19
Lap
Belt
Maintenance
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1-20
Floor
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1-20
Body
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1-22
Fiberglass
Repair
. .
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1-23
Sheet
Metal
Repair
. .
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1-25
Seats
.
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1-25
Mirrors
andSun
Visor
.....
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1-26
Radiator
Grille
....
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1-27
End
Cap
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1-27
Special
Tools
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1-28
Two
keys
are
furnished with
the
vehicle
.
Each
key
has
a
different
cross
section
so
that
it
can
be
inserted
only
in
certain
locks
.
The
key
with
a
square
head
is
for
the
ignition
switch
only
.
The
key
withan
oval
head
fits
the
side
entrance
door
lock,
the
glove
box,
and
the
external
utilities
compartment
.
All
models
have
ignition
and
glove
compartment
lock cylinders
incorporating
coded
keyways
and
keys
.
The
code
letter
is
located
on
the
key
shank
and
the
code
number
is
stamped
on
the
knock-out
por-
KEY
INFORMATION
tion
of the
key
head
.
These
numbers
identify
the
locks
in
which
the
keys
are
used
and
are
required
when
ordering
or
making
new
keys
.
Notch
dept
information
will
be
provided,
on
cur-
rent
production
keys,
upon
request
through
the
manufacturer
of
your
key
cutting
equipment
or
his
locksmith
association
.
Also
he
will
be
able
to
furnish
a
conversion
package
for
your
cutter,
if
required,
for
grinding
new
keys
.
1-
2
BODY
Entire
vehicle
shouldbe
regularly
inspected
for
condition
of
paint
and
for
corrosion
damage,
with
particular
attention
given
to
chrome
.
Inspection
shouldbe
made
more
frequently
in
freezing
weather
due
to
the
corrosive
effect
of
road
deicing
materials
(salt,
calcium
chloride,
etc
.)
on
metal
.
If
inspection
discloses
any
evidences
of
corrosion,
paint
failure,
or
bare
metal,
corrective
measures
as
outlined
under
"Painting"
(later in this
section)
shouldbe
immedi-
ately
employed
.
Body
painted
surfaces
and
chrome
plating
should
be
protected
by
a
coating
of
wax,
applied
at
regular
intervals
.
Periods
between
applications
should
be
sufficiently
short
to
assure
continuous
protection
of
Dust
and
loose
dirt
that
accumulate
on
interior
fabric
trim
should
be
removed
frequently
with
a
vacuum
cleaner,
whisk
broom
or
soft
brush
.
Vinyl
or
leather
trim
should
be
wiped
clean
with
a
damp
cloth
.
Normal
cleanable
trim
soilage,
spots
or
stains
can
be
cleaned
with
the proper use
of trim
cleaners
available
through
General
Motors
Dealers
or
other
reputable
supply
outlets
.
IMPORTANT
:
Do
not
use
commercial
paint,
chrome
or
glass
cleaners
on
interior
bright trim
or
painted
surfaces
.
If
cleaning
is
required,
luke-
warm
water
and
a
neutral
soap
may
be
used
.
Before
attempting
to
remove
spots
or
stains
from
upholstery,
determine
as
accurately
as
possible
the
nature
and
age
of the
spot
or
stain
.
Some
spots or
stains
can
be
removed
satisfactorily
with
water
or
mild
soap
solution
(refer
to
"Removal
of
Specific
Stains"
later
in this
section)
.
For
best
results,
spots
or
stains
shouldbe
removed
as
soon
as
possible
.
Some
types
of
stains
or
soilage
such
as
lipsticks,
some
inks,
certain
types of
grease,
mustard,
etc
.,
are
extremely
difficult
and,
in
some
cases,
impossible
to
completely
remove
.
When
cleaning
this
type
of
stain
or
soilage,
care
must
be
taken
not
to
enlarge
the
soiled
area
.
It is
sometimes
more
desirable to
have
a
small
stain
thanan
enlarged
stain
as
a
result
of
at-
tempted
cleaning
.
CAUTION
:
When
cleaning
interior
do
not
use
volatile
cleaning
solvents
such
as
:
ace-
tone,
lacquer
thinners,
enamel
reducers,
nail
polish
removers
;
or
such
cleaningmaterials
as
laundry
soaps,
bleaches
or reducing
agents
(except
as
noted
in
the
instructions
EXTERIOR
MAINTENANCE
INTERIOR
MAINTENANCE
the
finish
;
30 days
after delivery,
and
at
least
once
a
year
thereafter
.
Any
goodbody
wax
can
beused
for
both
painted
and
chrome
surfaces
.
Wax
shouldbe
applied
immediately
after
vehicle
has
been
cleaned
.
NOTE
:
Calcium
chloride
and
other
salts,
road
tar,
excretion
from
insects,
("treesap"),
chemi-
cals
from
factory
chimneys
and
other
foreign
matter
may
permanently
damage
paint
and
chrome
.
Frequent,
regular
washing
and
a
thorough
cleaning
after
exposure
is
recom-
mended
to
prevent
damage
by
thesesubstances
.
Use
either
cold
or
lukewarm
water
.
Never
wash
vehicle
in
direct
rays of
the
sun
and
always
wait
until
painted
surfaces
have
cooled
.
on
"Cleaning
Fabrics"
and
"Removal
of
Specific
Stains
.")
Never
use
carbon
tetra-
chloride,
gasoline,
or
naphtha
for
any
clean-
ing
purpose
.
The
above
materials
may
be
toxic
or
flammable,
or
may
cause
damage
to
interior
.
INTERIOR
GLASS
The
interior
glass
surface
should
be
cleaned
on
a
periodic basis
for
continued
good
visibility
.
A
com-
mercial
household
glass
cleaning
agent
containing
ammonia
will
removenormal
tobacco
smoke
and
dust
films
sometimes
causedby
ingredients
used
in
vinyls,
plastics,
or
other
interior
trim
materials
.
CLEANING
FABRICS
IMPORTANT
:
Be
sure vehicle
is
well
ventilated
while
using
the
following cleaning
agents
.
Fol-
low
manufacturer's
recommendations
in
using
such
products
.
CLEANING
FABRICS
WITH
CLEANING
FLUID
This type
of
cleaner
shouldbe used
for
cleaning
stains
containing
grease,
oil,
or
fats
.
Excess
stain
shouldbe
gently
scraped
off
trim with
a
clean
dull
knife or
scraper
.
Use
very
little
cleaner,
light
pres-
sure,
and
clean
cloths
(preferably
cheesecloth)
.
Cleaning
action
with
cloth
shouldbe
from
outside
of
stain
towards
center
and
constantly
changing
to
a
clean section of cloth
.
When
stain
is
cleaned
from
fabric,
immediately
wipe
area briskly
with
a
clean
absorbent
towel
or
cheesecloth
to
help
dry
area
and
prevent
a
cleaning
ring
.
If
ring
forms,
immediately
clean
entire
area
or
panel
section
of
the
trim
assem-
bly
.
NOTE
:
Sometimes
a
difficult
spot
may
require
a
second
application
of
cleaning
fluid
followed
im-
mediately
by a
soft
brush
to
completely
remove
the spot
.
CLEANING
FABRICS
WITH
DETERGENT
FOAM
CLEANERS
This type
of cleaner
is
excellent
for
cleaning
gen-
eral
soilage
from
fabrics
and
for
cleaning
a
panel
section
where
a
minor
cleaning
ring
may
be
left
from
spot
cleaning
.
Vacuum
area
to
remove
excess loose
dirt
.
Always
clean
at
least
a
full
trim
panel
or section
of
trim
.
Mask
adjacent
trim
along
stitch
or
weld
lines
.
Mix
detergent
type
foam
cleaners
in
strict
ac-
cordance with
directions
on
label
of
container
.
Use
foam
only
on
a
clean
sponge
or
soft
bristle
brush-
Do
not
wet
fabric
excessively
or
rub
harshly
with
brush
.
Wipe
clean
with
a
slightly
damp
absorbent
towel or cloth
.
Immediately
after
cleaning
fabric,
dry
fabric
with
a
dry
towel
or
hair
dryer
.
Rewipe
fabric
with
dry absorbent
towel
or
cloth to restore
the
lus-
ter
of
the
trim
and
to
eliminate
any
dried
residue
.
REMOVAL
OF
SPECIFIC
STAINS
CANDY-Chocolate,
use
cloth
soaked
in
luke-
warm
water
;
other
than
chocolate,
use
very
hot wa-
ter
.
Dry
if
necessary,
clean
lightly
with
fabric
cleaning
fluid
.
CHEWING
GUM-Harden
gum
with
ice
cube
and
scrape
off
with
dull
knife
.
Moisten
with
fabric
cleaning
fluid
and
scrape
again
.
FRUIT
STAINS,
COFFEE,
LIQUOR,
WINE,
SOFT
DRINKS,
ICE
CREAM
AND
MILK-
Wipe
with
cloth
soaked
in
cold
water
.
If
necessary,
Test
windshield,
windows
and
vehicle
under
flooring
for
leaks
by
spraying
water
under
pressure
against vehicle
while
assistant
inside
marks
points
of
leakage,
if
any
exist
.
If
location
of leak
has
been determined
to
be
around
windshield
or
rear
glass,
dry
surface
and
ap-
DUST
AND
WATER
LEAKS
BODY
1-
3
clean
lightly
with
fabric
cleaning
fluid
.
Soap
and
water
is
not
recommended
as
it
might
set
the
stain
.
CATSUP-Wipe
with
cloth
soaked
in
cool
wa-
ter
.
If
further cleaning
is
necessary,
use
a
detergent
foam
cleaner
.
GREASE,
OIL,
BUTTER,
MARGARINE
AND
CRAYON-Scrap
off
excess
with
dull
knife
.
Use
fabric
cleaning
fluid
.
PASTE
OR
WAX
TYPE
SHOE
POLISH-
Light
application
of
fabric
cleaning
fluid
.
TAR-Remove
excess
with
dull
knife,
moisten
with
fabric
cleaning
fluid,
scrape
again,
rub
lightly
with
additional
cleaner
.
BLOOD-Wipe
with
clean cloth
moistened
with
cold
water
.
Use
no
soap
.
URINE-Sponge
stain
with
lukewarm
soap
suds
from
mild
neutral
soap
on
clean
cloth,
rinse
with
cloth
soaked
in
cold
water
;
saturate cloth
with
one
part
household
ammonia
and
five
parts water,
apply
for
one
minute,
rinse
with
clean,
wet
cloth
.
VOMITUS-Sponge
with
clean cloth
dipped
in
clean,
cold
water
.
Wash
lightly
with
lukewarm
water
and
mild
neutral
soap
.
If
odor
persists,
treat
area
with
a
water-baking
soda
solution
(one
teaspoon
bak-
ing
soda
to
one cup
of
tepid
water)
.
Rub
again
with
cloth
and
cold
water
.
Finally,
if
necessary,
clean
lightly
with
fabric
cleaning
fluid
.
BALL
POINT
INK-Try
rubbing
alcohol
.
If
stain
remains
after
repeated
applications,
no
other
measure
should
be
tried
.
LIPSTICK-Difficult
to
remove
.
Cleaning
fluid
works
on some
brands
.
If
stain
remains
after
re-
peated
applications,
do
not
try
other
measures
.
MUSTARD-Damp
sponge with
warm
water,
then
rub
detergent
on
dampened
stain
and
work
into
fabric
.
Repeat
several
times
.
Some
discoloration
may
remain
.
ply
rubber
cement
.
Apply
cement
to
outside,
both
between
glass
and
weatherstrip
and
between
wea-
therstrip
and body
.
If
the
leak
is
around any
side
window
it
will
be
necessary
to
remove
the
window
and
install
a
new
seal
.
This manual suits for next models
5
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