warning GMC C-SERIES 1999 Service Manual
Page 222 of 328
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6-24 What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL coolant which won't damage
aluminum parts. If you use this coolant mixture, you
don't need to add anything else.
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle's coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable water
and DEX
-COOL coolant.
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don't have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
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6-26
Surge Tank (Caterpillar Diesel Engines)
When your engine is cold, the coolant level should be at
the COLD level, or a little higher, on the coolant
recovery tank with the gasoline engine, or at the COLD
FULL mark, visible through the surge tank, with the
diesel engine.
If this light comes on and
stays on, it means you're
low on engine coolant.
See ªLights, Low Coolant Warning Lightº in the Index
for further information.
Adding Coolant
If you need more coolant, add the proper DEX
-COOL
coolant mixture at the coolant recovery tank or the
surge tank.
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6-29 What to Use
To determine what kind of fluid to use, see
ªRecommended Fluids and Lubricantsº in the Index.
NOTICE:
When adding power steering fluid or making a
complete fluid change, always use the proper
fluid. Failure to use the proper fluid can cause
leaks and damage hoses and seals.
If your power steering fluid level is low, this can
cause the PRIMARY BRAKE or AUX BRAKE
warning lights to come on. If either light remains
on after you have added power steering fluid to
the proper level, then shut off the engine for
10 seconds. This should reset the brake warning
lights. If one or both lights stay on, though,
then see ªHydraulic Brake Warning Lightsº in
the Index.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer's instructions before use. If you will be
operating your vehicle in an area where the temperature
may fall below freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap labeled WASHER FLUID ONLY.
Add washer fluid until the tank is full.
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6-57
CAUTION:
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make the wheel nuts become
loose after a time. The wheel could come off and
cause an accident. When you change a wheel,
remove any rust or dirt from the places where the
wheel attaches to the vehicle. In an emergency,
you can use a cloth or paper towel to do this; but
be sure to use a scraper or wire brush later, if you
need to, to get all the rust or dirt off.
How Often to Check
Wheel tightness is so important you should have a
technician check nut tightness on all wheels with a
torque wrench every 1,000 miles (1 600 km).
When your vehicle is new or when a wheel or fastener is
new you should have a technician tighten the wheel
stud and rim clamp nuts, with a torque wrench, at
100, 500 and 1,000 miles (160, 800 and 1 600 km).
The reason for this is that the clamping system has to
seat before the fasteners will stay tightened.
Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted.
If wheel nuts keep coming loose, replace the wheel.
If the wheel leaks air, replace it.
Your dealer will know the kind of wheel you need.
CAUTION:
A leaking wheel could fail without warning. A
wheel designed for tubeless tires could be leaking
because it is damaged. Don't use an inner tube or
some other thing to try to stop the leaking. Get a
new wheel of the proper type.
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6-59
Appearance Care
Remember, cleaning products can be hazardous. Some
are toxic. Others can burst into flame if you strike a
match or get them on a hot part of the vehicle. Some are
dangerous if you breathe their fumes in a closed space.
When you use anything from a container to clean your
vehicle, be sure to follow the manufacturer's warnings
and instructions. And always open your doors or
windows when you're cleaning the inside.
Never use these to clean your vehicle:
Gasoline
Benzene
Naphtha
Carbon Tetrachloride
Acetone
Paint Thinner
Turpentine
Lacquer Thinner
Nail Polish Remover
They can all be hazardous
-- some more than others --
and they can all damage your vehicle, too.Don't use any of these unless this manual says you can.
In many uses, these will damage your vehicle:
Alcohol
Laundry Soap
Bleach
Reducing Agents
Cleaning the Inside of Your Vehicle
Use a vacuum cleaner often to get rid of dust and loose
dirt. Wipe vinyl, leather, plastic and painted surfaces
with a clean, damp cloth.
Cleaning of Fabric/Carpet
Your dealer has two cleaners, Multi-Purpose Interior
Cleaner and Capture Non
-Solvent Dry Spot and Soil
Remover for cleaning fabric and carpet. They will clean
normal spots and stains very well. You can get
GM
-approved cleaning products from your dealer.
(See ªAppearance Care and Materialsº in the Index.)
Here are some cleaning tips:
Always read the instructions on the cleaner label.
Clean up stains as soon as you can
-- before they set.
Carefully scrape off any excess stain.
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7-25
Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake (see ªParking
Brakeº in the Index if necessary) and the
regular brakes.
NOTE: Do not use the accelerator pedal, and be
ready to turn off the engine immediately if it starts.
3. On automatic transmission vehicles, try to start the
engine in each gear. The starter should work only in
PARK (P), if equipped, or NEUTRAL (N). If the
starter works in any other position, your vehicle
needs service.Automatic Transmission Shift Indicator Check
Check that the indicator points to the gear chosen.
Steering Check
Be alert for any changes in steering action, abnormal
front tire wear or steering wheel position. An inspection
or service is needed when the steering wheel is harder to
turn or has too much free play, or if there are strange
sounds when turning or parking.
Brake System Check
Be alert to illumination of the low air warning lamp or
for the tone alarm, or changes in braking action, such as
repeated pulling to one side, unusual sounds when
braking or increased brake pedal travel. Make sure air
brake system reservoirs are drained daily with full
system air pressure, and check system for leaks. Any of
these conditions could indicate the need for brake
system inspection and/or service.
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7-26
Engine Cooling System Service
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the outside
of the radiator and air conditioning condenser. To help
ensure proper operation, a pressure test of the cooling
system and pressure cap is recommended at least once
a year.
Exhaust System Check
Be alert for any changes in the sound of the exhaust
system or any smell of fumes. These are signs the
system may be leaking. Have it checked and/or repaired
at once. Refer to ªEngine Exhaustº and ªRunning Your
Engine While You're Parkedº in the Index.
Windshield Wipers and Washers Check
Check operation and condition of the wiper blades.
Check the flow of the washer spray.
Defroster Check
Move the control to the defrost symbol and the fan to HI
or the high symbol. Then check the airflow from the
ducts at the inside base of the windshield.Mirrors and Sun Visors Check
Check that friction joints hold mirrors and sun visors
in place.
Seat Adjuster Check
When adjusting a manual seat, be sure seat adjusters
latch by attempting to move the seat after latching.
Lamps Check
Check panel lighting, warning lights, indicator lights
and interior lamps. On the outside, check: license plate
lamps, sidemarker lamps, reflectors or lights on outside
mirrors, headlamps, parking lamps, identification and
clearance lamps, taillamps, brake lamps, turn signals,
backup lamps and hazard warning flashers. Have
headlamp aim checked at once if beams seem
improperly aimed.
Glass, Mirrors, Lamps and/or Reflectors
Condition Check
Look for broken, scratched, dirty or damaged glass,
mirrors, lamps or reflectors that could reduce the view
or visibility or cause injury. Replace, clean or
repair promptly.
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9-1
Section 9 Index
A
ir
Brake System Warning Light 2-59 . . . . . . . . . . . . . . . . . . . .
Cleaner 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cleaner Filter 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Compressor Filter 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conditioning 3-5, 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conditioning Refrigerants 6-77 . . . . . . . . . . . . . . . . . . . . . .
Dryer 6-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filter Restriction Indicator 6-17 . . . . . . . . . . . . . . . . . . . . . .
Suspension 2-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Brake Systems 6-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Dryer 6-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Alcohol Injector 6-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Moisture Ejector 6-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Alcohol Injector 6-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Alignment and Balance, Tire 6-51 . . . . . . . . . . . . . . . . . . . . . .
AM-FM Stereo 3-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AM-FM Stereo with Remote Cassette Tape Player 3-10 . . . . .
Antenna 3-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Antifreeze 6-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Anti-Lock
Brakes 4-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake System Warning Light 2-61, 4-7 . . . . . . . . . . . . . . . .
Appearance Care 6-59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appearance Care Materials 6-66 . . . . . . . . . . . . . . . . . . . . . . . Apply Park Brake Warning Light 2
-60 . . . . . . . . . . . . . . . . . .
Ashtray 2-47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Audio Systems 3-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission Fluid 6-18 . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission Shift Indicator Check 7-25 . . . . . . . .
Auxiliary Power Jacks 2-48 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Axle, Rear 6-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Airshift Control 2-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Lock Control 2-41 . . . . . . . . . . . . . . . . . . . . . . .
Fluid Capacity 6-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shift Motor 6-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tw o-Speed Electric Shift Control 2-17 . . . . . . . . . . . . . . . .
Towing 5-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery 6-42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery, Jump Starting 5-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake
Adjustment 6
-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Brake Systems 6-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Parking Brake 2-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electric/Hydraulic Parking Brake 2-25 . . . . . . . . . . . . . . . .
Electric/Hydraulic Parking Brake Fluid 6-36 . . . . . . . . . . . .
Exhaust 2-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fluid 6-30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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9-2
Brake (Continued)
Four-Wheel and Six-Wheel Drum 6-33 . . . . . . . . . . . . . . .
Four-Wheel Disc 6-32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hydraulic Systems 4-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Master Cylinder 6-30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parking 2-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pedal Travel 6-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Propshaft Brake Burnish Procedure 2-24 . . . . . . . . . . . . . . .
Releasing Air-Operated Parking Brakes 5-15 . . . . . . . . . . .
Replacing System Parts 6-35 . . . . . . . . . . . . . . . . . . . . . . . .
System Check 7-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Warning Lights 2-57 . . . . . . . . . . . . . . . . . . . . . . . .
Brake, Anti-Lock 4-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Braking 4-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Braking in Emergencies 4-9 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Break-In, New Vehicle 2-5 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Capacities and Specifications 6-74 . . . . . . . . . . . . . . . . . . . .
Carbon Monoxide 2-29, 2-30 , 4-27 . . . . . . . . . . . . . . . . . . .
Cassette Tape Player Care 3-12 . . . . . . . . . . . . . . . . . . . . . . . .
Center Passenger Position 1-22 . . . . . . . . . . . . . . . . . . . . . . . .
Certification/Tire Label 4-28, 6-67 . . . . . . . . . . . . . . . . . . . . .
Changing a Flat Tire 5-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Charging System Light 2-56 . . . . . . . . . . . . . . . . . . . . . . . . . .
Chassis Lubrication 6-37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check Gages Light 2-67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Your Restraint Systems 1-36 . . . . . . . . . . . . . . . . . .
Chemical Paint Spotting 6-65 . . . . . . . . . . . . . . . . . . . . . . . . . . Child Restraints 1
-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Securing in the Center Seat Position 1-31 . . . . . . . . . . . . . .
Top Strap 1-30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cigarette Lighter 2-47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Breaker Block, Instrument Panel 6-69 . . . . . . . . . . . . .
Cleaner, Air 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cleaning
Fabric 6
-59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Glass 6-62 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inside of Your Vehicle 6-59 . . . . . . . . . . . . . . . . . . . . . . . . .
Instrument Panel 6-61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Outside of Your Vehicle 6-63 . . . . . . . . . . . . . . . . . . . . . . . .
Safety Belts 6-61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Problems 6-60 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tires 6-64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vinyl 6-61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windshield and Wiper Blades 6-62 . . . . . . . . . . . . . . . . . . .
Clock, Setting the 3-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch Pedal Free Travel 6-37 . . . . . . . . . . . . . . . . . . . . . . . . .
Comfort Controls 3-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Component Box 6-44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Connections, Trailer 2-49 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Control of a Vehicle 4-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant 6-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater, Engine 2-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recovery Tank 5-22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Surge Tank 5-29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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9-4
Engine (Continued)
Fuse Blocks 6-69, 6-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Identification 6-67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil 6-13, 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Filters and PCV Valves 6-77 . . . . . . . . . . . . . . . . . . . . .
Oil Level Check 7-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overheating 5-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Road Speed Governor 2-54 . . . . . . . . . . . . . . . . . . . . . . . . .
Running While Parked 2-30 . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Over-Crank Protection 2-7 . . . . . . . . . . . . . . . . . . . .
Starting 2-7, 2-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Oil 6-13, 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additives 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking 6-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engines 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Life Monitor 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Gage 2-66 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Used 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What Kind to Use 6-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
When to Add 6-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
When to Change 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ether Injection System 6-46 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust
Brake 2
-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine 2-29, 2-30, 4-27 . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Check 7-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fabric Cleaning 6-59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filling a Portable Fuel Container 6-8 . . . . . . . . . . . . . . . . . . . .
Filling Your Tank 6-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filter
Air Cleaner 6
-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Compressor 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Oil 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filterminder Gage 2-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Finish Care 6-63 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Finish Damage 6-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flashers, Hazard Warning 5-2 . . . . . . . . . . . . . . . . . . . . . . . . .
Flat Tire, Changing 5-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fluid Leaks Check 7-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fluids and Lubricants 7-28 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Footnotes 7-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
French Language Manual ii. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Towing 5
-10, 5-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Wheel Bearings with Oil-Filled Hubs 6-47 . . . . . . . . . .
Fuel
Diesel Engine 6
-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filling a Portable Container 6-8 . . . . . . . . . . . . . . . . . . . . . .
Filling Your Tank 6-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filter 6-44, 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gage 2-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gasoline Engine 6-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tank Capacity 6-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Water in Fuel 6-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuels in Foreign Countries -- Gasoline 6-6 . . . . . . . . . . . . . . .
Fuses and Circuit Breakers 6-69 . . . . . . . . . . . . . . . . . . . . . . .
Fusible Links 6-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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