JAC Heavy truck. Service Manual — part 5

131

APPEARANCE CARE

130

●

Do not stop your engine. The engine power is needed for supplying compressed air for the brakes and operating the

power steering system.

●

Be sure that the transaxle is in neutral. Also, be sure that ignition key is in the "ON" postion .

CAUTION:

●

When your vehicle is towed, remove the rear axle shafts.

●

When your engine or brakes are defective, make sure that your vehicle is towed by a towing vehicle designed for the

purpose.

●

The engine brake, exhaust brake and parking brakes (air over hydraulic brake vehicle) do not function.

Precautions when the vehicle fails

●

If anything goes wrong during operation, calm yourself and gradually reduce the vehicle speed, while paying attention

to the vehicles behind, and stop the vehicle at a point the closest to the shoulder of the road.

●

Set the hazard warning switch to "ON" to make the hazard lamps flash. At the same time, place a red flag or a red

lamp for indication of the trouble. If the indication of the trouble is not made, there is a danger of an approaching vehicle

bumping into your vehicle.

●

Be sure to apply chocks to the tires. If the propeller shaft or rear axle is defective, the parking brakes might not be

applied.

●

Check the faulty point. If you can correct it

yourself, proceed after making sure that neither your safety nor other's

will be jeopardized.

●

If you cannot correct the trouble yourself, contact the nearest service shop.

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cle. Even though the mud appears to be dry, it can still retain moisture and promote corrosion.

High temperatures can also accelerate corrosion of parts that are not properly ventilated so the moisture can be dis鄄

persed. For all these reasons, it is particularly important to keep your car clean and free of mud or accumulations of

other materials. This applies not only on the visible surfaces but particularly to the underside of the car.

TO HELP PREVENT CORROSION

You can help prevent corrosion from getting started by observing the following:

Keep Your Car Clean

The best way to prevent corrosion is to keep your car clean and free of corrosive materials. Attention to the underside of

the car is particularly important.

●

If you live in a high -corrosion erea where road salts are used, near the ocean, areas with industrial pollution, acid

rain, etc. You should take extra care to prevent corrosion. In winter, hose off the underside of your car at least once a

month and be sure to clean the underside thoroughly when winter is over.

●

When cleaning underneath the car, give particular attention to the components under the fenders and other areas that

are hidden from view. Do a thorough job; just dampening the accumulated mud rather than washing it away will accel鄄

erate corrosion rather than prevent it. Water under high pressure and steam are

particularly effective in removing ac鄄

cumulated mud and corrosive materials.

●

When cleaning lower door panels, rocker panels and frame members, be sure that drain holes are kept open so that

moisture can escape and not be trapped inside to accelerate corrosion.

13 2

PROTECTING YOUR JAC FROM CORROSION

By using the most advanced design and construction practices to combat corrosion, JAC produces cars of the highest

quality. However, this is only part of the job. To achieve the long-term corrosion resistance your JAC can deliver, the

owners cooperation and assistance is also required.

Common Causes of Corrosion

The most common causes of corrosion on your car are:

●

Road salt, dirt and moisture that is allowed to

accumulate underneath the car.

●

Removal of paint or protective coatings by stones, gravel, abrasion or minor scrapes and dents which leave unpro鄄

tected metal exposed to corrosion.

High-Corrosion Areas

If you live in an area where your car is regularly exposed to corrosive materials, corrosion protection is particularly im鄄

portant. Some of the common causes of accelerated corrosion are road salts, dust control chemicals, ocean air and in鄄

dustrial pollution.

Moisture Breeds Corrosion

Moisture creates the conditions in which corrosion is most likely to occur. For example, corrosion is accelerated by high

humidity, particularly when temperatures are just above freezing. In such conditions, the corrosive material is kept in

contact with the car surfaces by moisture that is slow to evaporate.

Mud is a particular enemy of corrosion protection because it is slow to dry and holds moisture in contact with the vehi鄄

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CAUTION:

When washing your vehicle, pay attention to the following points.

●

Be sure to stop the engine beforehand.

●

Cover the starter, genarator and other electrical devices to prevent direct ex鄄

posure to steam of a steam cleaner or water.

●

Do not spray water against the air cleaner inlet and its vicinity.

Waxing

Waxing the vehicle will help prevent the adherence of dust and road chemi鄄

cals to the paintwork. Apply a wax solution after washing the vehicle, and ply

wax at least once every three months.

Polishing

The vehicles should only be polished if the paintwork has become stained or

lost its luster Mat-finish parts and plastic bumpers must not be polished; pol鄄

ishing these parts will stain them or damage their finish.

Spot Cleaning

Don't use gasoline, strong solvents or corrosive cleaning agents. These can

damage the finish of the car. To remove road tar, use turpentine on a clean,

soft cloth. Be gentle.

To remove dead insects or tree sap, use warm water and mild soap or car -

washing solution. Soak the spot and rub gently. If the paint has lost its luster,

use a commercial car-cleaning polish.

134

APPEARANCE CARE

In order to maintain the value of you r vehicle, it is necessary to perform regular maintenance using the proper proce鄄

dure. Be sure to maintain your vehicle in compliance with any pertinent environ mental pollution control regulations.

Carefully select the materials to be used for washing, etc.to be sure that they do not contain corrosives; if in doubt, con鄄

tact an authorized JAC dealer for assistance in the selection of these materials.

Washing

Chemicals contained in the dirt and dust picked up from the road surface can damage the paint coat and body of your

vehicle if left in prolonged contact.

Frequent washing is the best way to protect your vehicle from this damage.

This will also be effective in protecting it from environmental elements such as

rain, snow, salt air, etc. Do not wash the vehicle in direct sunlight. Park the ve鄄

hicle in the shade and spray it with water to remove dust. Next, using an am鄄

ple amount of clean water and a vehicle washing brush or sponge, wash the

vehicle from top to bottom. Use a mild vehicle washing soap if necessary.

Rinse thoroughly and wipe dry with a soft cloth. After washing the vehicle (in鄄

cluding washing in an automatic vehicle wash), carefully clean the joints and

flanges of the doors, etc. where dirt is likely to remain. Clean the engine room

and the bottom of chassis with steam cleaner. Be careful, at this time, not to

blow steam onto such electrical devices as starter, generator, etc.

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VEHICLE MAINTENANCE REQUIREMENTS

136

CLEANING THE INTERIOR

To Clean the Vinyl Upholstery

To clean the vinyl upholstery, first remove loose dirt and dust with a vacuum cleaner. Then apply a solution of mild soap

or detergent and water using a clean sponge or soft cloth. Allow this to stay on the surface to loosen the dirt, then wipe

with a clean damp sponge or cloth. If all the dirt stains are not removed, repeat this procedure until the upholstery is

clean. Do not use gasoline, solvent, paint thinner or other strong cleaners.

Cleaning the Carpets

Use a foam-type carpet cleaner. Cleaners of this type are available in aerosol cans in liquid form or powder. Read the

instructions and follow them exactly. Using a vacuum cleaner with the appropriate attachment, remove as much dirt from

the carpets as possible. Apply the foam following the manufacturers directions, then rub in overlapping circles. Do not

add water. These cleaners work best when the carpet is kept as dry as possible.

Cleaning the Seat Belts

To clean the seat belts, use a cloth or sponge with mild soap or detergent and warm water. Do not use strong deter鄄

gents, dye, bleach or abrasive materials on the seat belts as this may weaken the fabric.

While cleaning the belts, inspect them for excessive wear, cuts, fraying or other signs of damage and replace them if

necessary.

Cleaning the Windows

You may use any household window cleaner on the windows.

Any Questions?

If you have any questions about the care of your car, consult your JAC dealer.

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Interval(Kilometers)×1000

1

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

Interval(Mile)×1000

0.6 3

6

9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60

NO. Item

Power Line

1

Transmission oil

I

Replace every 24,000km

2

Clutch/brake pedal free play and operation condition

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

3

Clutch oil

Replace every 7 year or 24,000km

Driving system

1

Rear axle oil

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

2

Propeller shaft universal jiont,slip jiont＆Center bearing

I

I

I

I

I

3

Front, rear wheel hub bearing damage＆free play

I

I

I

I

I

4

Wheel stub bolts and nuts

I

I

5

Tire pressure and damage

I

I

I

I

I

I

I

I

I

I

6

Tire rotation

Replace every 20,000km～25,000km

Steering system

1

Power steering gear oil

I

I

2

Steering system oil leakage

I

I

I

I

I

I

I

I

I

I

3

Overall axle alignment

Adjust the valve clearance every 40,000km after first adjusment of 5,000km

4

Steer angle and stopper bolt retightenning

I

I

I

5

Steering free play ＆ linkage for looseness
(in driving the engine)

I

I

I

I

I

I

I

I

I

I

I

I

Service brake

1

Brake fluid

R

R

R

2

Brake system for fluid leakage

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

3

Brake lining clearance

Inspect and replace if necessary

4

Brake lining for wear

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

5

Brake drum for wear

I

I

139

138

SCHEDULED MAINTENANCE

The following maintenance services must be performed to assure good vehicle control and performance. Keep receipts

for all vehicle services to protect your warranty.

Where both kilometers and time are shown, the frequency of service is determined by whichever occurs first.

R: Replace

I: Inspect and after inspection, clean adjust, repair or replace if necessary

Interval(Kilometers)×1000

1

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

Interval(Mile)×1000

0.6 3

6

9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60

NO.

Item

Engine Control System Maintenance

1

Air,fuel oil coolant for leakage

I

I

I

I

I

I

I

I

I

I

2

Oil filter

R

R

R

R

R

R

R

R

R

R

R

3

Air cleaner element

I

I

I

R

I

I

I

R

I

I

I

R

I

I

I

R

I

I

I

R

4

V-belt tention and damage

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

5

Injection tightening

I

I

I

I

I

6

Injection pressure and injection condition of the nozzle

I

I

I

I

I

7

Injecting timing

I

I

8

Fuel feed pump filter

I

I

I

I

I

I

I

I

I

I

9

Fuel filter

Replace every 2000km～2500km

10

Air compressor

I

I

11

Removal of foreign matter in the fuel tank

I

I

I

I

I

I

I

I

I

I

12

Valve clearance

Adjust the valve clearance every 40,000km after first adjusment of 5,000km

13

Cylinder head bolts

I

I

I

14

Engine operation condition
(Starting,Idling speed,Max speed,Acceleration)

I

I

I

I

I

I

I

I

I

I

I

I

15

Engine coolant(or every 2 years)

R

R

R

R

R

R

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Engine oil and filter

The engine oil and filter should be changed at those intervals specified in the maintenance schedule. If the car is being

driven in severe conditions, more frequent oil and filter changes are required.

Valve clearances

An incorrect valve clearance will not only result in rough engine operation but will also cause excessive noise and re鄄

duced engine output.

Inspect valve clearance and adjust as required while the engine is cold.

Fuel lines and connections

Check the fuel lines and connections for leakage and damage. Replace any damaged or leaking parts immediately.

Fuel filter

A clogged filter can limit the speed at which the vehicle may be driven, damage the emission system and cause hard

starting. If an excessive amount of foreign matter accumulates in the fuel tank, the filter may require replacement more

frequently.

After installing a new filter, run the engine for several minutes, and check for leaks at the connections.

Vacuum and crankcase ventilation hoses

Inspect the surface of hoses for evidence of heat and/or mechanical damage. Hard and brittle rubber, cracking, tears,

cuts, abrasions, and excessive swelling indicate deterioration. Particular attention should be paid to examining those

hose surfaces nearest to high heat sources, such as the exhaust manifold.

Inspect the hose routing to assure that the hoses do not come in contact with any heat source, sharp edges or moving

Interval(Kilometers)×1000

1

5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

Interval(Mile)×1000

0.6 3

6

9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60

NO.

Item

Service brake

6

Brake pedal free play

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

7

Air dryer

Inspect every 1 year or 50,000

8

Air dryer heater plug

Inspect every 2 year or100,000km

Parking brake

1

Parking brake function

Inspect every 5,000km and every 2,000km after first adjustment
of 5,000km or if necessary

2

Drum for wear

I

I

I

I

I

I

I

I

I

I

3

Lining for wear

I

I

I

I

I

I

I

I

I

I

Suspension

1

Suspension for damage

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

2

U-bolt＊

Adjut the U.bolt every 20,000km after first adjustment of 5,000km
or if necessary

3

Leaf spring for damage

I

Inspect every 5,000km or if necessary

4

Shock absorbers for oil leakage or damage

I

Inspect every 5,000km or if necessary

Chassis

1

Bolts and units on chassis and body

I

Inspect every 5,000km or if necessary

2

Oil for cab tilt

Inspect every 1 year ,replace every 2 year

3

Tractor coupler function and kingpin bearing
for damage and looseness

I

I

4

Pintle hook and lunette-rye

I

I

140

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143

reservoir. Use only hydraulic brake fluid conforming SAE J706

Brake drums and linings

Check for scoring, burning, leaking fluid, broken parts, and excessive wear.

Brake pads, calipers and rotors

Check the pads for excessive wear, discs for run out and wear, and calipers for leaking fluid leakage.

Parking brake

Inspect the parking brake system such as parking brake lever, cables, and so on. For detailed service procedures, refer

to the Shop manual.

Exhaust pipe connections, muffler and suspension bolts

Check the exhaust pipe, muffler, and suspension connections for looseness or damage.

Steering gear box, linkage and boots

With the car stopped and engine off, check for exccessive free-play in the steering wheel, check the linkage for bends

or damage. Check the dust boots and ball joints for deterioration, cracks, or damage. Replace any damaged parts.

Wheel bearing grease

Check the wheel bearings and grease according to the maintenance schedule. For inspection procedures, see Shop

Manual.

142

component which might cause heat damage or mechanical wear. Inspect all hose connections, such as clamps and

couplings, to make sure they are secure, and that no leaks are present. Hoses should be replaced immediately if there

is any evidence of deterioration or damage.

Fuel hose, vapor hose and fuel filler cap

The fuel hose, vapor hose and fuel filler cap should be inspected at those intervals specified in the maintenance sched鄄

ule. Make sure that a new fuel hose, vapor hose or fuel filler cap is correctly replaced. Consult your JAC dealer if you

have any questions.

Air cleaner filter

A genuine JAC part is recommended for replacement of the air cleaner filter.

Drive belts

Inspect all drive belts (water pump and alternator) for evidence of cuts, cracks, excessive wear or oiliness, and replace

if necessary. Drive belts should be checked periodically for proper tension and adjusted as necessary.

Engine coolant

The coolant should be changed at those intervals specified in the Vehicle Maintenance Requirements Section.

Brake hoses and lines

Visually check for proper installation, chafing, cracks, deterioration and any leakage. Replace any deteriorated or dam鄄

aged parts immediately.

Brake fluid

Check brake fluid level in the brake fluid reservoir. The level should be between % - and "H"marks on the side of the

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Cleaning of element

Dry dust buildup

Blow clean compressed air evenly up and down from inside the element to

loosen and remove the dust.

NOTE:

Do not strike the element or hit it against other object. Make sure that the pres鄄

sure of the compressed air used for cleaning does not exceed 2 kgf/cm

2

.

Checks to make after drying

Check the filter paper for damage, pinholes and thin portions. If a defective

portion or broken packing is evident, replace the element with a new one.

144

PAPER ELEMENT TYPE AIR CLEANER MAINTENANCE

The air cleaner element should be cleaned or replaced when the dust indica鄄

tor light in the cluster comes on.

Removal and installation of element

1. Loosen the wing nut ① and remove the cover

② straight and withdrow the element ③.

2. Check the element for contamination.

The cleaning procedure varies with the degree of contamination.

3. After cleaning, install by reversing the removal procedure.

NOTE:

The inner element should be replaced when he outer element is replaced.

Note that the inner element is not washable.

CAUTION:

Make sure that the element and cover are securely installed, ff th ey are loose,

the cleaner will absorb dust and will fail to function properly.

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Bleed air by the following procedure

1. Loosen the air bent cock on the top of the fuel filter.

2. Turn the priming pump couterclckwise with

pressing down and then the

pump piston is pushed out by a spring.

3. Operate the priming pump until the fuel without air bubble flow out.

4. Tighten the air bent cock and fix the pump piston by turning clockwise with

pressing down.

5. Start the engine and check for fuel leaks.

CHECK RADIATOR AND RADIATOR HOSE

Check the radiator 2, radiator hose 3, etc. for water leaks.

Check for the traces of water leaks on the g round where the vehicle has been

parked. If there are water leaks in the cooling system, take the vehicle to the

nearest service shop for service.

146

REMOVAL OF CONDENSATE FROM WATER SEPARATOR

Check the water separator about once a week. Remove the condensate before

the float 1 in the water separator reaches the position of the red line2.

To remove the condensate proceed as follows:

1. Loosen the plug 3 to discharge the condensate.

2. After the float has come down, tighten the plug.

3. Wipe clean the water separator and its neighborhood.

4. Check for fuel leaks.

BLEED OF FUEL FILTER

If the engine stops by being used up fuel, cleaning the fuel system or chang鄄

ing the fuel filter the engine does not start through fuel is replenished due to

be come air into the fuel system .

Air should be removed from the fuel system to make it start your engine.

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STEERING WHEEL FREE PLAY

Lightly rock steering wheel at the center position to check for free play. If the

free play exceeds 15 to 35 mm, have the steering wheel adjusted by your

nearest Authorized Dealer.

CHECKING BRAKE PEDAL FREE PLAY

Check the pedal free play by depressing the pedal with finger.

The pedal free play is the stroke made by the pedal moves until you feel a

change in resistance.

This is the brake pedal free play. The freeplay should be within the limits spec鄄

ified in the illustration below. If it is not, have it inspected by your JAC dealer

and adjusted or repaired if necessary.

148

Adjustable Generator freeplay

Slightly loosen the generator attaching bolts and adjust by moving the whole

generator.

CAUTION:

●

After adjustment, tighten the bolts and nuts firmly. Overtension will cause

damage to the V-belt and bearing.

●

Make sure that the V-belt is not fouled with oil or grease. Oil or grease will

cause the belt to slip and will shorten its life.

●

When a V-belt is defective, make sure that the two V-belts are replaced as

a set.

REMOVAL OF CONDENSATE WATER

FROM AIR TANK

Open all drain cocks to remove the water collected in the air tank.

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1) Master cylinder play:

Approx. 0.24 in. (6 mm)

2) Master cylinder

3) Play adjusting nut

NOTE:

If the adjustment cannot be made to this play specification, the clutch disc is

worn down to the service limit. Take the vehicle to your nearest service facility

for correction.

BLEEDING OF CLUTCH PIPING

If there is air in the piping, the clutch will be hard to disengage.

When the fluid reservoir tank has been emptied, be sure that the clutch piping

is bled. Have an assistant in bleeding the piping and proceed as follows:

1. Fill the clutch fluid reservoir tank with brake

fluid up to the "MAX" level.

Since the level falls during the bleeding operation, add brake fluid to prevent

emptying the tank.

150

CLUTCH PEDAL PLAY

The clutch pedal play will decrease as the disc wears. If it is not adjusted, the

clutch will slip, making it impossible to operate the vehicle. When the clutch

pedal play has decreased to less than 8.3 in.

(210 mm), adjustment is re鄄

quired.

Check the pedal play by depressing the pedal with finger. Depressing the

pedal will make you feel resistance in two stages. The pedal play is the stroke

made by the pedal until it reaches the second stage and is 0.24 to 0.31 in. (6

to 8mm) standard. The play in the first stage is the master cylinder play. In the

second stage, it is the clutch booster push rod play. The play is easier to

check when the compressed air pressure is lower. If it is out of specification,

have it inspected and adjusted or repaired if necessary.

Adjust the clutch master cylinder play, which is the movement of the pedal up

to the first resistance encountered when the pedal is depressed with your fin鄄

ger. Adjust this play to about 6 mm (0.24 in.) by turning the center belt of the

master cylinder push rod.

After adjusting, firmly tighten the nut on the center

belt while holding the belt in position with a corench.

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CHECKING THE BRAKES

CAUTION:

Because brakes are essential to the safe operation of the car, it is suggested

that they be checked and inspected by your JAC dealer. The brakes should

be checked and inspected for wear at those intervals specified in the vehicle

maintenance schedule in Section 6-3.

Checking the Brake Fluid Level

WARNING:

Use caution when handling brake fluid. It can damage your vision if it get into

your eyes. It will also damage your vehicles paint if spilled on it and not re鄄

moved immediately.

To Check the Fluid Level (If installed)

The fluid level in the brake fluid reservoir should be checked periodically. The

level should be between the "L' and "H" marks on the side of the reservoir. If

the level is at or below the "L" mark, carefully add fluid to bring it up to "H". Do

not overfill.

152

2. Remove the rubber cap from the air bleeder of the clutch booster, mount

one end of a transparent vinyl hose, and put the other end in a bowl contain鄄

ing brake fluid.

3. Depress the clutch pedal several times. After the stroke has settled, keep

the pedal depressed.

Let the assistant loosen the air bleeder to

discharge the air along with the

brake fluid. Let him tighten the air bleeder immediately after air has been dis鄄

charged.

NOTE:

If the brake fluid is discharged from the air bleeder, the stroke of the pedal will

change. Tighten the air bleeder immediately after the pedal has touched the

stopper.

4. After the air bleeder has been tightened, release the pedal.

5. Repeat steps 3 and 4 until there are no more air bubbles in the brake fluid

that runs out from the air bleeder. As a final step, tighten the air bleer firmly

and install the rubber cap.

6. Check the fluid level in the fluid reservoir tank and add brake fluid up to the

"H" level. Depress the clutch pedal to check for fluid leaks.

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Checking and changing the engine coolant

WARNING:

Do not remove the surge tank cap when the engine is hot. When the engine is hot, the coolant is under pressure and may

erupt through the opening if the cap is removed. You could be seriously burned if you do not observe this precaution.

Do not remove the surge tank cap until the radiator is cool to the touch.

Handling of cooling system

Engine overheating is caused by the low coolant level or rust and scale accumulations in the cooling system. If the radi鄄

ator clogs very badly or coolant is very dirty, perform cleaning and coolant replacement as described below. If the

coolant level is low, add coolant as necessary.

Replacement of coolant

If the radiator clogs badly or coolant becomes dirty, replace coolant immediately regardless of the specified replace鄄

ment intervals. In making this kind of replacement, be sure to clean the cooling system by the procedure shown in

'Cleaning method".

Cleaning method

Run the engine at idle to heat the coolant to 90℃or higher. Then clean by the following procedure.

1. Open the radiator and engine drain cocks to

drain the coolant.

2. After complete draining, close each drain cock and fill the system with city water.

3. Close the drain cocks and fill the system with city water. Run the engine for a while and drain the system.

154

COOLANT LEVEL AND LEAKS IN COOLING SYSTEM

If lamp is illuminated add the coolant after removing the surge tank cap at firt.

Check reservoir tank for the coolant level.The coolant level should be with in

the range 1 shown in the illustration. If the level is low, add coolant by refer鄄

ence to "Replacement of coolant".

CAUTION:

●

Check the coolant level before vehicle operation while the engine is cold.

●

After checking the coolant level, be sure to reinstall the cap positively.

●

Be sure to add the coolant containing antirust or anti -freeze of the same

concentration as the coolant in the cooling system.

●

Do not check the coolant level after the engine has been stopped. Be sure

to check the level when the coolant temperature is low.

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CAUTION:

●

Be sure to use anti-freeze at the concentration most appropriate for the atmospheric temperature within a range from

30 to 53%. If the concentration is below

30%, the anti-corrosion property will be adversely affected. If the concentration

is above 53%, the anti-freeze property will decrease and engine overheating will also be caused. Use anti-freeze at the

specified concentration.

●

If winter is over, be sure to drain the coolant containing antifreeze and put In genuine anti-rust "RADIPET 9".

156

Repeat this operation until a colorless, transparent water flows out from the drain cock.

4. Fill the radiator with city water containing genuine anti-rust 'RADIPET 9' or genuine anti-freeze at a specified con鄄

centration. Run the engine until the coolant is heated to the temperature (90℃) at which the thermostat opens, and bleed

air thoroughly from the cooling system.

5. Stop the engine and make sure that the coolant is at the proper level. If the coolant level is low, add city water.

CAUTION:

When the cooling system is cleaned, the coolant or cleaning solution is drained at elevated temperature. Therefore, be

careful not to get scalded.

Addition of coolant

If the warning lamp lights when the starter switch is set to "ON', the coolant level is low. Note that the procedure for

adding coolant varies according to the type of the engine cooling system on vehicle. Use city water as coolant and add

anti-rust or anti-freeze to have a specified concentration for prevention of engine or cooling system corrosion.

Do not use hard water from well river etc.

Antifreeze

Select proper concentration between 30 and 53% by reference to the table shown below.

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NOTE:

Be sure not to hurt yourself.

4. Turn the adjusting cam in the direction of the arrow until it is blocked.

Slightly back it off.

5. Insert a 0.4 mm (0.016 in.) thickness gauge over the entire width of lining

through the adjusting hole and turn the adjusting cam to adjust the clearance

to the extent that the thickness gauge can be pulled out with some resistance.

6. Each wheel has two adjusting holes at the front and rear. Be sure to adjust

both by the same method.

1) Adjusting hole

2) Adjusting cam

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ADJUSTMENT OF BRAKE SHOE CLEARANCE

Air over hydraulic brake vehicles

If the brake linings are worn and the clearance between the brake drum and linings (brake shoe clearance) increases, it

can be dangerous because the brake performance deteriorates.

If the BRAKE pilot lamp lights, adjust and bleed the system immediately.

Leakage of brake fluid also causes the BRAKE pilot lamp to light. Check for fluid leaks, too.

1. Apply chocks to the tires before the wheel to be adjusted is jacked up.

2. Strongly push the outside periphery of tire with both hands to check for wheel looseness. If the wheel is loose, it can鄄

not be correctly adjusted. Take the vehicle to your nearest service shop for correction.

3. Remove the dust plug from the shoe clearance adjusting hole.

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JAC HEAVY DUTY TRUCK

3. Start the engine to increase the compressed air pressure to more than 6.4

kgf/cm

2

(625kPa). Leave the engine running at idle.

4. Push the knob of the cab control valve to release the emergency brakes.

5. Remove the dust cap from the wheel brake inspection hole and check the

lining thickness. If the lining is worn down to the notch shown in illustration, it

is worn beyond the service limit. Have your nearest service shop replace the

linings. Make sure that the dust cap is reinstalled after inspection.

6. Turn the worm shaft of the slack adjuster in the direction that the push rod

extends until the worm shaft touches the stopper.

7. Back off the worm shaft 3 or 4 notches on the front wheels or 4 or 5 notches

on the rear wheels.

The notches are indicated by the clocks the worm shaft makes when turned.

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7. After adjustment, check the lining wear indicator of the adjusting cam. If the pointer of the indicator is not in the wear

range, the brake linings are worn down beyond the service limit. Have your nearest service shop replace the linings.

8. Turn the wheel in the forward direction and depress the brake pedal to stop rotation of the wheel. Thereafter, turn the

wheel to check for dragging. With slight foot pressure on the brake pedal, turn each wheel by hand, ensure that the front

wheels are slightly lighter to turn that the rear wheels or there is no gear difference, and that the right and left wheels are

about equal.

9. As a final step, install the dust plug. Operate the vehicle at slow speed and make brake tests to check for poor per鄄

formance, uneven braking and other troubles.

Air brake vehicles

If the brake linings are wom and the clearance between the brake drum and linings (brake shoe clearance) increases, it

can be dangerous because the brake performance deteriorates. Check and adjust the brake shoe clearance at regular

intervals.

●

The brake shoe clearance should be determined on the basis of the stroke of the brake chamber push rod. If the

push rod stroke exceeds 40 mm (1.57 in.) on the front wheels or 50 mm (1.97 in.) on the rear wheels when the brake

pedal is depressed all the way, adjust the clearance.

1. Apply chocks to the tires before the wheel to be adjusted is jacked up.

2. Strongly push the outer periphery of tire to check for wheel looseness. If the wheel is loose, it cannot be correctly ad鄄

justed. Take the vehicle to your nearest service shop for correction.

OWNER

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JAC HEAVY DUTY TRUCK