JAC Dumper truck. Service Manual — part 6

8. Measure the stroke made by the push red of the brake chamber when the
brake pedal is depressed all the way. Verify that the stroke is up to specifica鄄
tions given in the following table if it is out of specification, adjust with the
worm shaft.
Standard stroke of brake chamber push rod

9. Turn the wheel in the forward direction by hand and depress the brake
pedal to stop rotation of the wheel. Turn the wheel to check for dragging. With
slight foot pressure on the brake pedal, turn each wheel by hand to check that
the front wheels are slightly lighter to turn than the rear wheels or there is not
great difference and that right and left wheels are about equal.
10. As a final step, install the dust plug. Operate the vehicle at a slow speed
and perform brake tests to check for brake performance, uneven braking and
other troubles.

162

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

ENGINE OIL LEVEL
Position the vehicle on a level surface. The best time to check the oil level is
before operating the engine or about 30 minutes after stop of engine.
The checking procedure is as follows:
1. Wipe the level gauge 1 well with a cloth, insert it into the level gauge guide
2 and remove the gauge to check the oil level. The oil level should be between
"FULL' and "LOW" inscribed lines.
CAUTION:
If the oil level is checked when the engine is stopped before sufficient rise of oil
temperature, the detected level will be lower than the actual level, because
some oil accumulation in the engine does not flow back into the oil pan.
2. If the level is Iow, add engine oil through the filler cap 3. After addition of
engine oil, allow more than six minutes and then recheck the oil level.
3. If a badly contaminated engine oil is obvious when checking the oil level,
replace the engine oil irrespective of the service intervals.

163

OIL FILTER

荫

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.

荫

If the filter is blocked the warning light is on and if the oil pressure is low

the buzzer sounds at the same time. Replace it independent of the mileage.

荫

An element assembly cannot be reused.

Replacement of filter type
1. Put an empty container below the oil filter drain hose. Remove the air
bleeding plug and drain the engine oil out.
2. Disassemble the case by pulling the center bolt on the oil filter out and re鄄
move the element.
Use the genuine parts when you assemble. Replace the element and rub
packing of the case simultaneous. Apply engine oil on the rub packing before
assembling. Tighten the center bolt with specified torque 5.5依0.5 kg.m.
3. When you replace only the oil filter replenish the engine oil.
4. Crank the engine and check the oil leakage and the oil level later.

164

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

CAUTION
Be very careful when draining the engine oil as it may be hot enough to burn you.
Dropped oil may cause a fire. Wipe and clean each part in the engine room.

Replacement of cartridge type
If the filter is blocked, the warning light is on when the RPM is high.
Replace it independent of the mileage
If the oil pressure decreases the warning light also is on ant the buzzer sounds simultaneous. But the parking brake is
applied on it does not sound.
1. Put an empty container below the oil filter and remove the drain plug. Drain the engine oil out.
2. When the draining is finished pull the oil filter out with a wrench.
3. Use the genuine parts when you assemble. Assemble the rub packing on top of the filter after applying the engine oil
on.
4. When you replace the oil filter replenish the engine oil.
5. Start your engine. Check whether the oil leaks. The checking should be done before driving and after.

CAUTION
Split oil may cause a fire. Wipe and clean each part in the engine room.
Never reuse the filter assembly.

165

WINDSHIELD WASHER FLUID LEVEL
Check to ensure that windshield washer fluid is at a proper level.

Operation of wipers

荫

Push the knob to check that the windshield washer fluid is sprayed at the

correct position.

荫

Turn the lever and check the wipers for proper operation.

NOTE:
Be sure to operate the windshield washer before the wipers are operated.
Do not operate the wipers on dry glass,
This can result in more rapid wear of the wiper blades and may scratch the
glass.

166

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

TURBOCHARGER
Principle of turbo charger operation
Turbo engine is a device that produces more power by supplying sufficient air
into the combustion chamber by using the energy of exhaust gas is usually
wasted in the general engine.
The exhaust gases are accelerated in the turbine housing and directed onto
the turbine wheel to turn it.
This spins the compressor wheel, which results in the intake air being forced
into the engine cylinders.
As the intercooler is installed that improves the fuel economy and power of the
engine, while reducing harmful exhaust gases to a minimum.

Intercooler
The intake air compressed by the turbocharger increases to 170~C and as a
result, power of the engine is limited by engine overheated. The intercooler
cools the heat. This improves the combustion efficiency and as a result, it in鄄
creases that the fuel economy and power of the engine, while reducing harm鄄
ful exhaust.

167

Precautions while operating
1. Check the oil level and oil pressure
Before starting the engine, measure the crankcase oil level. As soon as the
engine starts, check oil pressure indicator for nor mal rise.
2. Warm the engine up
After the engine starts, avoid sudden acceleration or sudden start.
Enough RPM is needed before starting engine until the engine is warm for 3 to
10 minutes.
3. No staring suddenly and No accelerating heavily
If you accelerate heavily, start suddenly or when you turn off the engine sud鄄
denly it may damage to the engine and turbocharger parts.

CAUTION

荫

If running a vehicle without air cleaner filter, foreign material drawn can de鄄

stroy engine and turbo charger.

荫

When you turn off an engine suddenly may damage bearing, hi-speed rota鄄

tion part of turbo charger inside, so let the engine run at idle for sufficient time.

168

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

BATTERY INSTRUCTIONS
Check the battery fluid level and specific gravity at regular intervals.
CAUTION:

荫

The battery generates highly Inflammable gases.

Take special care not to use a fire or produce sparks near the battery.

荫

The battery fluid contains sulfuric acid.

In case of contact with the skin or clothes, immediately wash away with a large
amount of clean water and seek medical help.

Cleaning of battery terminals
1. Clean the battery terminals if they are stained or corroded. If there is white
powder on the terminals, wash with hot water.
2. Remove and polish the terminals with a wire brush or emery paper if they
are markedly corroded.
3. Apply a thin coat of grease to the terminals after cleaning and tightening.
NOTE:
The terminals must be firmly tightened. Before cleaning the terminals, make
sure the caps are installed securely to prevent foreign matter from entering the
battery.

169

Fluid Quantity
The fluid level should be between the "UPPER' and "LOWER' level lines. If the
level is low, add distilled water up to the 'UPPER' line.
NOTE:
If your battery has only one level line, the line indicates the "LOWER" level
(lowest).
If your battery has no level line, the fluid level should be between 10 and
15mm above the plates.
If the level is low, add distilled water until it is 15mm above the plates.
NOTE:
After addition of water, be sure to charge the battery (by operating the vehicle),
because otherwise the fluid could be frozen in winter.
Specific gravity
Measure the specific gravity. If it is less than 1.220 (at a fluid temperature of
20~C), recharge the battery.
NOTE:
The standard specific gravity of battery is 1.260 to 1.270 (at a fluid temperature
of 20~C).

170

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

REPLACEMENT OF FUSE
If the electrical system is out of order, open the cover and check for a blown
fuse in the following sequence.
1. Open the cover.
2. Remove the circuit checker from the reverse side of the cover.
3. Insert the female terminal of the circuit checker into 'CHECKER' ground ter鄄
minal and touch the male terminal to the fuse top surface.
4. If the lamp lights, the fuse is good.
The headlamp circuit should be checked with the head light switch at lighting
position.
5. Replace the defective fuse.
CAUTION:

荫

Use of a fuse out of specification or wire could be dangerous. Be sure not

to use a substitute fuse. Make sure that a blown fuse is replaced with a gen鄄
uine fuse. If a defective point cannot be located, have inspection made at your
nearest service shop.

荫

Do not pour water over the relay and fuse box. Do not put your foot on the

box or kick it. When the inside of the cab was cleaned with water, remove the
water completely through the drain hole in the floor and then tilt the cab.

171

CENTRALIZED LUBRICATION SYSTEM(If installed)
C.L.S (Centralized Lubrication System) is the device to lubricate a proper quantity of grease into all major chassis parts
(except propeller shaft) automatically at regular interval of time through an exclusive lubrication pipe with a control unit
during driving.
Inspecting & Replenishing Grease
Pour grease to the MAX remarked on the reservoir tank.

荫

Inspect or add grease every 2 months

荫

Recommended grease: NGL 100,000

CAUTION

荫

When the grease is poured into the reservoir tank it must be a pure thing.

荫

Replenish grease through the exclusive lubrication inlet to avoid entering foreign material.

NOTE
Lubricate manually with pressing the manual lubrication switch beside the timer as required especially in rainy time or af鄄
ter washing a vehicle. Lubricating interval has specified 6 hour when the vehicle is delivered. Do not necessary to adjust
again.
CLS Inspection

荫

Pour grease into the reservoir tank. Turn the ignition key to the ON position and push the manual button.

荫

Check the operating condition of the pump. If it is normal open a plug on the end of the fractionator. The pump

should be operated continuously until the grease is flowed.

荫

Turn the main switch off after bleeding air completely from the main pipe and then lock the plug.

172

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

荫

Turn the battery switch on for 15 seconds and off for 5 repeatedly and then check whether the grease lubricates.

荫

Check the indicator lamp is off when the pump is operated.

CAUTION
Do this procedure once a day before driving.
NOTE

荫

The auto grease indicator light is turned on at the same time with operation of the pump, and after 3 seconds the light

is off. The pump is operated for 154 seconds at one time.

荫

If the auto grease indicator light is illuminated continuously even after 3 seconds there is a malfunction in the CSL.

Have the CLS inspected and repaired by an authorized JAC dealer.
CAUTION

荫

Turn the main switch off after having the pump worked for 154 seconds although the lamp is off after 3 seconds nor鄄

mally.

荫

Inspect the tightening condition of leak age of the conjunction part and grease line.

Management of CLS

荫

Check that there is the grease lubricated at a necessary part around the refueling hole and leaking grease at con鄄

necting part of thelubricator and fractionator, periodically.

荫

Wash the grease container with benzene or mineral oil. Never use trichloroethelene or equivalent solvent.

荫

Maintain the main switch is OFF when the vehicle is not working for a long time.

荫

If you work the CLS when the tank is empty, it may be damaged. Inspect frequently.

173

TIRE ROTATION
Tires should be rotated every 8,000 km (5,000miles). If you notice that tires are
wearing unevenly between rotations, have the car checked by a JAC dealer so
the cause may be corrected.
After rotating, adjust the tire pressure and be sure to check wheel nut tight鄄
ness.
NOTE:

荫

Do not mix biss-ply and radial-ply under any circumstances.

荫

In ace double rear wheel, the difference of outer diameter between outer

wheel and Inner wheel Is less than 12mm.

DOUBLE REAR AXLE
1. Front tire
2. Rear front tire
3. Rear reartire
Spare tire

174

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

PRECAUTIONS BEFORE HIGH SPEED OPERATION
The higher the vehicle speed, the more heat the tires generate, and eventually
there is a danger or a burst.
The heat generated by the tires varies greatly with the tire pattern, tire inflation
pressure, load and speed. Pay attention to the following points.

荫

Keep the tires inflated at normal pressure.

荫

Avoid overloading.

The lug type pattem tires are not suited for high speed operation, as they tend
to skid. If your vehicle is equipped with the lug type tires, care should be tak鄄
en not to operate it at very high speed.
Exercise special car when controlling the steering wheel or applying brakes on
a wet road surface.

175

TROUBLESHOOTING
Refer to the following causes when the vehicle fails, and fake the corrective action as soon as possible. If the causes
can not be founded out, have the vehicle checked and repaired by an authorized dealer.

When the starter switch is in 'S' position, engine doesn't start.
Starter does not rotate at all or rotates slowly.

176

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

Engine stalls when speed is reduced

Engine overheating

177

Starter rotates but engine does not start

Low torque

178

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

poor exhaust emissions

Excessive fuel consumption

179

Excessive engine oil consumption

Engine oil pressure does not rise

180

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

Steering wheel and vehicle make abnormal vibration

Hard steering

181

Run-down battery

Lamps do not light

182

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

DUMP TRUCK

183

BEFORE DRIVING

Before driving your tipper, the following information is important for proper care and economical operation and long ser鄄
vice life of your JAC tipper.
1. Check if the oil in the hydraulic oil tank is sufficient.
The hydraulic oil is regulated as follows: in winter in the northern areas it is mobile oil No.3 or YC-N46D hydraulic oil,
low freezing; in the middle and southern areas of China it is mobile oil No.2 mixed with 30% of machine oil or YB-N45
antiwear hydraulic oil.
2. Check if the operational valve leaks air and if the air roads and oil roads leak when the air pressure is not lower than
0.78Mpa.
3. Check the lifting structure and observe whether the main parts such as hydraulic cylinder, gear pump, operational
valve, etc. function normally and whether there are problems such as binding, jumping, sliding, abnormal voice etc.
when the dump truck are unloaded
4. Check whether the locking system of the back carriage functions normally in the process of lifting.
5. Check whether it has all the tools and technical documents.

184

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

RUNNING-IN OF NEW DUMP TRUCK

1. The running-in period of the dump truck is measured according to the numbers of the lifting of the carriage. Every
1000 times of lifting is counted as one running-in period.
2. In the running-in periods, the load must be controlled. It is regulated as follows:

荫

Within 100 times, it is better not to load the dump truck or load it with a small volume of cargos.

荫

100-300 times, the load shall be not larger than 50% of the rating load.

荫

300-600 times, the load shall be not larger than 65% of the rating load.

荫

600-1000 times, the load shall be not larger than 80% of the rating load

3. After 100 times of lifting of the carriage, the hydraulic oil should be completely changed.
4. In the running-in periods, every 50 times of lifting or every one week the lubrication point should be lubricated at least
once.
5. In the running-in periods, check condition of the bracket bolt, U type bolt and other linking bolts of the hydraulic
cylinder.

185

WORKING PRINCIPLE AND OPERATION INSTRUCTIONS OF HYDRA-ULIC DUMPING MECH鄄
ANISM

The dump trucks produced in our company have different control methods: air-controlled, electricity-controlled, con鄄
trolled by electricity and hydraulic system, and controlled by electricity and air. Before operating the vehicle that you
choose, you have to fully understand its dumping control system and master its control method.

186

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

Working Principle and Operation Instructions of Air-controlled Dumping Mechanism
1. Working principle (see Diagram 1)

187

When the control handle is pushed to the "lift" position, the compressed air in the reservoir will flow to the power take-off
cylinder, thus push the power take-off gear and make the gear pump start to work. Have been pressed by the gear
pump, the hydraulic fluid in the fuel tank will flow into the lower chamber of the hydraulic cylinder through the single
check valve and the selector valve to push the piston rod and lift the carriage via the connecting rod.
When the piston of the hydraulic cylinder reaches the oil drain hole, the high-pressure oil will flow back into the fuel tank
through the oil drain hole and the pipe. Meanwhile, the carriage will stop lifting and maintain the maximum lifting angle.
When the control handle is pushed to the "fall" position, the compressed air in the reservoir will flow to the selector valve
and keep it in the open state. At that time, the upper and lower chamber of the hydraulic cylinder is interlinked with the
fuel tank, and the carriage's weight will force the oil in the lower chamber of the hydraulic cylinder to flow through the
selector valve and flow back into the fuel tank, thus enable the carriage to fall down. When the control handle is at the "
pause" position, the selector valve is closed. The gear pump will stop working and the oil in the lower chamber of the
hydraulic cylinder will be sealed, enabling the carriage to stop at any position during the process of lifting or falling.

188

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

2. Operation Instructions

荫

Switching on the gear pump

Press the clutch pedal and push the control handle to the "lift" position. Re鄄
lease the clutch pedal smoothly and the gear pump will start working.

荫

Carriage lift

After the gear pump is started, the carriage begins rising. Increase the throttle
and the lifting will be faster. The increase of the throttle is not permitted when
the carriage is lifted to the maximum lifting angle. Otherwise, the cylinders and
other tilting mechanisms will be damaged.

荫

Carriage fall

Press the clutch pedal and push the control handle to the "fall" position, the
carriage will start to fall. When the carriage is back at its original place, push the
control handle to "pause" so as to avoid the accidental lifting of the carriage.

荫

Pause control

1. During the process of carriage lift, press the clutch pedal and push the
control handle to "pause"
2. During the process of carriage fall, push the control handle to "pause".
Note: The operation of lifting after pausing is th e same as "Switching on the
gear pump" and "Carriage lift". As for the operation of falling after pausing, you
only need to push the control handle to "fall".

The position of the handle

(from left to right)院Lift寅Pause寅Fall

189

Working Principle and Operation Instructions of Dumping Mechanism controlled by Electricity and Hydraulic System
1. Working principle (see Diagram 3)

190

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

When the control handle is pushed to the "lift" position and the switch is switched on, the electromagnetic priority valve
will be opened. The compressed air in the reservoir will flow to the power take-off cylinder, thus push the power take-
off gear and make the gear pump start to work. Being pressed by the gear pump, the hydraulic fluid in the fuel tank will
flow into the lower chamber of the hydraulic cylinder through the single check valve, push the piston rod and lift the car鄄
riage via the connecting rod.
When the piston of the hydraulic cylinder reaches the oil drain hole, the high-pressure oil will flow back into the fuel tank
through the oil drain hole and the pipe. At the same time, the carriage will stop lifting and maintain the maximum lifting
angle.
When the control handle is pushed to "fall", the control valve is opened and the lower chamber of the hydraulic cylinder
is interlinked with the fuel tank. The carriage's weight will force the hydraulic fluid in the lower chamber of the hydraulic
cylinder, through the control valve, back into the fuel tank, thus enable the carriage to fall smoothly. At the same time,
the gear pump is still working, and the high-pressure oil is flowing back into the fuel tank through the single check valve
and the control valve.
Turn off the switch and the gear pump will stop. Push the control handle to the "lift" position and the oil in the lower
chamber of the hydraulic cylinder will be sealed, and enable the carriage to stop at any position during the process of
lifting or falling.

191

2. Operation Instructions

The position of the handle(from left to right)院Lift寅Fall

192

OWNER爷S MANUAL

JAC HEAVY DUTY TRUCK

荫

Switching on the gear pump

Press the clutch pedal and turn the switch to the "on" position. Then release the clutch pedal smoothly and the gear
pump will start working.

荫

Carriage lift

After the gear pump is started, push the control handle to "lift" and the carriage begins rising at an uniform speed. In鄄
crease the throttle and the lifting will be faster. The increase of the throttle is not permitted when the carriage is lifted to
the maximum lifting angle.

荫

Carriage fall

Press the clutch pedal; turn off the switch; push the control handle to the "fall" position, then the carriage will start to fall.
The speed of falling can be regulated by the opening degree of the control valve.

荫

Pause control

If you want to stop the carriage during the process of lifting, you only need to press the clutch pedal. Meanwhile, the
control valve is still on the "lift" position. But if the pause will last for a long time, you need to turn off the switch. If you
want to stop the carriage during the process of carriage fall, push the control handle from "fall" to "lift".
Note: If you want to resume the lifting after pausing, release the clutch pedal and turn off the switch.

If you want to resume the falling after pausing, push the control handle to "fall".

193