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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Component Identification
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0-2
Hoisting Instructions . ......... . . ... . ... . . ... . .... . .... . ................ . ........ . . . . . . ...

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Jack Usage Instructions . .
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Towing
Vehicle .. .
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. .0-4
Engine, Chassis,
and
Body Maintenance Schedule
....... . .... . ... . . ... . .... . .... . .... . ... . . ......... . ... . ... . . .
0-6
Explanation of Maintenance Schedule .................. . ............. . ... . . ... . .... . .... . .... . .... . ......... . ... . ... . . . 0-7
Recommended Fluids and Lubricants ...... . ........... . ........ . .... . ... . . ... . ..... . ... . . ... . .... . .... . .... . ... . . . . . . .0-11
Lubrication Details ...... . ... . . ... . ......... . .... . ... . . ... . ... . ... . . . . . . ... . ... . . ... . ..... . ... . . ... . .... . .... . . . . . . ... . .... . ... . ... 0-12
Winterization and Vehicle Storage . . . ... . ... . . ... . ... . ... . . . . . . ... . ... . . ... . . .... . ... . . ... . .... . .... . . . . . . ... . .... . ... . ... 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 .