Chaoyang Diesel With

High Quality

Operation Manual

CYQD32 Series Diesel Engine

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Foreword

CYQD 32 series diesel engine is a new generation diesel engine with high

quality, which is manufactured with international advanced level technology from

Japanese Nissan Diesel. This series includes CYQD32, CYQD32EGR, CYQD32T,

CYQD32Ti four versions. It features with compact in volume, light in weight,

strong in power, capable of climbing, low fuel consumption, easy to start, long life,

low noise, low exhaust pollution and so on. They mainly complete with light-duty

truck, pick-up and light-duty bus, if they are varied, they will apply in other power

mechanicals.

CYQD 32 series diesel engines are advance in performance targets，they have

good structure and all the performance targets have reached the advanced level. In

the meantime, cylinder-block, crankshaft, piston and other key components were

increased strength and toughness, and have had higher service reliability by

adopting new structure, new technology. So if you purchase this kind of engine or

the vehicles with such engine and all kinds of mechanisms will gain better

economic benefit.

The operation manual is comply the purpose of effective operation and

maintenance so as to bring this series diesel engine into full play and keep diesel

engines in constantly well technical condition. The details of diesel engine

operation instruction, maintenance and trouble shooting are given in this manual. If

drivers and service men operate according to the specification, it may surely

benefit.

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Information and data in this manual are identified with our present products. As

this series diesel engine will be continuously improved as technical development

and requirement by customer, therefore specification listed in this manual are

subjected to chance without notice. Please pay close attention to the differences and

our latest version of operation manual.

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Cautions

1. Diesel engine VE pump plunger must be in the specific range.

2. After engine starts or before stops, it must idle 3-5 minutes, in order to heat

engine or cool evenly. Generally, you should not change speed and loading, and

idling time can’t excess 10 minutes, no loading and big throttle operation are

strictly prohibited.

3. Before new engine using or change oil, oil filter and stopping for long time

(about one week) to turbocharger and turbocharger inter-cooled diesel, must loose

inlet adapter on super-charge and refill cleaning oil, and make turbo rotor bearing

gain full primary lubrication (when filled oil, pay closed attention to using container,

tool, connection component and surrounding environment must clean).

4. Diesel engine oil must be in accordance with the specifications of the manual and

choose the label and regularly change it in accordance with the specifications of the

manual. It is necessarily deposited and filtered before applying it.

5. Soft water must be used as coolant, or the cooling system circuits may be

blocked.

6. The cleanliness of the air aspirated by diesel engine has important influences to

the life of engine. It is not allowed the engine working without air filler or the air

filler lost efficacy. I t is not allowed the engine running when the intake system

leaking.

7. If the air filter was clogged, it will make the end of compressor of charger leak,

so we must maintenance regularly and change filter.

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8. When change the primary oil filter after it is full. Apply little oil on the surface of

the seal ring before fix it. Tight the filter by hand until it touched the seal ring, then

tight another 3/4 round.

9. Due to VE pump is lubricated with diesel, in order to ensure the service life of

VE pump, must change the element of the diesel filter and its diesel.

10.You must remember that, according to “The Regulation for New Engine Run-in

Maintenance” for your new engine in the technical service stations of Dongfeng

Chaoyang Diesel Co., Ltd., otherwise you can’t get guarantee. The technical service

centers of Dongfeng Chaoyang Diesel Co., Ltd., to serve you whole-heart in the

nearest station, and perform “run-in maintenance” free of charge.

Please to read Service Manual with engine about detail information

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Contents

Full load performance curve of Model CYQD32 series diesel engine

Main specifications and technical targets of CYQD32 series diesel engine

Chapter I Technical Performance of Diesel Engine

A. Technical specification of diesel engine

B. Mainly technical data of diesel engine

Chapter II Operation of the Diesel Engine

A. Fuel, lubrication oil and cooling water

B. Preparing before starting

C. Starting of diesel engine

D. Running-in of diesel engine

E. Operation of diesel engine

F. Stop of diesel engine

Chapter III Maintenance of Diesel Engine

A. Routine maintenance

B. Maintenance about ruining 2000km (about 50 hours)

C. Maintenance about ruining 8000km (about 200 hours)

D. Maintenance about ruining 45000km (about 1000 hours)

E. Judgment of main repairing period of diesel engine

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F. Maintenance in winter operation

Chapter IV Regular Adjustment of Diesel Engine

A. Valve clearance

B. Fan belt

C. Opening pressure and quality of spray about injector

Chapter V Main Parts and System of Diesel Engine

A. Cylinder block

B. Cylinder head

C. Crankshaft and flywheel

D. Piston and connecting rod

E. Transmission system

Chapter Ⅵ Supply System of Diesel Engine

A. Diesel engine combustion and combustion chamber

B. Exhaust gas recirculation system (EGR)

C. Turbo-charge system

D. Turbo-charge Inter-cooling system

E. Fuel supply system

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Chapter Ⅶ Auxiliary System of Diesel Engine

A. Lubrication system

B. Cooling system

C. Accessory machine

D. Clutch

E. Instruction for preheating device

F. Increasing device for idle

Chapter Ⅷ Trouble & Shooting

A. Difficult in start

B. Unstable speed of idle

C. Insufficient power

D. Big fuel consumption

E. Big oil consumption

F. Water temperature is high in engine outlet

G. Exhaust white smoke

H. Exhaust black smoke

I. Oil pressure is low

J. Trouble caused by turbocharger

Meaning of the Unit Symbol Used

in This Manual and Its Conversion

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Main specifications and technical targets of CYQD32 series diesel engine CYQD32 CYQD32EGR CYQD32T CYQD32Ti type Vertical, in-line, water cooled, 4 stroke Number of cylinders Bore × Stroke(mm)

4---99.2×102mm

Type of combustion chamber

Swirl chamber

Displacement (L) 3.153 Firing order 1-3-4-2 Aspiration method Natural

aspirated EGR Turbo charge Turbo charge

inter-cooled Max. power kW(Ps)

75.8 (103) 75.8 (103) 80.9 (110) 96 (130) 101.5(138)

Max. power (r/min) 3600 3600 3600 3600 Max. torque N.m (kgf.m)

216 216 221 280 313

Max. torque speed (r/min)

2200 2200 2000 2000

Min specific fuel consumption(g/kW.h)

230 230 230 225

Oil vs fuel (%) < 0.2 < 0.2 < 0.2 < 0.2

Exhaust temperature°C

≤700 ≤700 ≤700 ≤700

Idling speed (r/min) 700±50、850±50 (When the air conditioner is on. ) Max. steady idling speed (r/min)

4700±100

Compression ratio 22:1 Steady governor

rate (%) 17.5

ZEXEL 0.416 0.468 0.527 0.736 Plunger lift of injection pump (mm) DENSO 0.416 0.45 0.594

Emission EUR Ι EUR Ц EUR Ц EUR Ц Noise (dBA)(360r/minfull load)

93.0 93.0 93.0 93.0

Cool start (℃) -35 -35 -35 -35 Overall dimensions (mm) (L×W×H)

72×597×677 721 × 597×677

721 × 701×715

721×701×665

Net mass (kg) 258 260 272 275

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Chapter I Technical Performance of Diesel Engine

A. Technical specification

1. Engine

Type vertical, in-line, water cooled, 4 stroke

Number of cylinders- Bore ×stroke (mm)

4---99.2×102mm

Cylinder bush no

Type of combustion chamber Swirl chamber

Displacement (L) 3.153

Firing order 1-3-4-2

Direction of rotation

(From the end of flywheel) counter clockwise

Starting method electric starting

Stopping method cut-off fuel supply

Lubrication method compression and splash lubrication

Cooling method forced and closed circuit

2. Accessory parts:

Oil pump gear type

Oil filter spiral

Oil cooler water cooled, built-in type

Water pump centrifugal type

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Thermostat Opening temperature at 76.5℃

Fan vanes axial flow

Fan clutch silicon oil fan clutch

Fuel injection pump VE distribute pump]

Injector single hole, axial needle, hole diameter is 1mm

Starter electromagnetic control type, 12V, 2.8Kw

Alternator 12V, 70A

B. Main technical data of diesel engine

1. Valve timing (according to crankshaft angle)

CYQD32 CYQD32EGR CYQD32T CYQD32Ti Intake valve opening (B.T.D.C)

16º 16º 19º 19º

Intake valve closing (A.T.D.C)

52º 52º 43º 43º

Exhaust valve opening (B.T.D.C)

66º 66º 60º 60º

Exhaust valve closing (A.T.D.C)

12º 12º 8º 8º

2. Between valve and rocker arm clearance (cool engine)

Intake valve 0.35mm

Exhaust valve 0.35mm

3. Compression clearance (at T.D.C., the clearance between piston top and

cylinder head bottom)

0.8~1.1mm

4. Oil pressure:

Idling oil pressure: 98kPa

Operation oil pressure: 196~490kPa

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5.Cooling water temperature 80~95℃ (when operation, cooling water

should not boil)

6. Oil capacity in oil sump

7L (Include oil filter)

6.3 L ( No oil filter)

7. Cooling water capacity:

9.5L (only engine)

8. Extension of fan belt

We compress the belt with 39N(4kgf), the single deflection should be between

10~15mm.

9. Main bolt tightening torque:

Cylinder head bolt First tightening torque: 39.3N.m

Second tightening torque: 63.7N.m

Third tightening torque: 900±100

Checking torque 113~132N.m(11.5~13.5kgf.m)

Main bear bolt 167~176N.m(17~18kgf.m)

Connecting rod nut 78~83N.m(8~8.5kgf.m)

Flywheel bolt 167~186N.m(17~19kgf.m)

Camshaft gear compress bolt 57~66N.m(5.8~6.8kgf.m)

Injection pump compress nut 59~69N.m(6~7kgf.m)

Crankshaft front nut 373~402N.m(38~41kgf.m)

Piston cooling nozzle bolt 29~39N.m(3~4kgf.m)

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Oil drain plug of oil sump 54~59N.m(5.5~6kgf.m)

Injector nut 29~39N.m(3~4kgf.m)

Nut of high pressure oil pipe 20~25N.m(22.5kgf.m)

Notice:

a. To twist the bolt of cylinder head with angle, the other bolts must twist

alternatively them according to specific order with 2-3 times.

b. If non-locking washer were used, pay special attention to tightening

torque.

c. Tightening with lubrication oil when assembly. If the thread of bolt was

damaged, replace it.

10. General bolt tightening torque: (unit: N.m)

M8 16~21

M10 29~39

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Chapter II Operation of Diesel Engine

To make diesel engine operate properly, not only can keep it in normal operate,

but also can prolong its life.

A. Fuel, lubrication oil and cooling water

1. Fuel:

Fuel: GB252 light diesel fuel can be used. Type of fuel and oil must be

chosen in light of seasons, climate according to the type of national standard. We

suggest that light diesel -35# can be used.

Fuel must be deposited for a 7 days and nights and filtered with silk cloth,

and oil filling tool must be clean.

2. Lubrication oil

Oil is CF-4 grade diesel or special oil for Dongfeng Chaoyang

CYQD32 diesel engine. It can be used as per the following table:

Oil brand Applicable ambient temperature

30# -5℃ ~ 30℃

40# Above 5℃

10W -20℃ ~ -5℃

5W/30 Above -25℃

15W/40 Above -30℃

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Please remember:

The mechanical load and heat load of this diesel engine both are very high,

every moving parts including turbocharger, they are all belong to high temperature,

high speed and precise moving parts, those have very strict requirement for the oil

quality, so must use specified oil, and select the suitable oil brand according to the

ambient temperature, change the oil in specified interval. Otherwise, it will be very

harmful to the diesel engine and shorten its service life.

Different brand of oil can’t be mixed to avoid bad chemical and physical

reaction to make oil deteriorate.

3. Coolant

Long term of effective coolant must be used, it not only good in cooling, but

also has the function of anti-frozen and anticorrosive. Due to the coolant hole is

very small, if use water as cooling media, it’s very easy to be blocked by scale and

incrustation.

B. Preparing before starting

Before starting diesel engine, normal check-up must be done following:

1. What about the different parts, and what about connections.

2. Whether about engine oil, cooling water and fuel capacity is sufficient,

not sufficient should be filled it.

3. Whether there is any leakage about oil, water and air, if it is leakage, we

should repair it at once.

4. What about electric circuit system is right, and storage battery is

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sufficient.

5. For the new diesel engine with turbocharger or stop for longer time

(more than one week), must open inlet adopter on the turbocharger, and fill certain

amount of lubrication oil (the type is the same with oil in the oil sump) so that the

turbocharger can get sufficient primary lubrication.

C. Starting of diesel engine

1. When starts the new vehicle, first should loose the hand supply pump in the

fuel system, press the hand supply pump up and down, let fuel go into the injection

pump through fuel water separator and fuel filter so that the injection pump can

have certain amount of fuel.

2. Pull the handle brake to the bottom, and put the control lever in idling

position.

3. In order to reduce the load of starter, loose the clutch, in the same time press

the accelerator pedal, and turn on the power with key. Observe if electric meter is

normal, then turn the key to the preheating shift, when the preheating light is off,

turn the key to starting position so as to start diesel engine.

4. After the engine started, should loose the key (it should return

automatically), or it will damage the engine.

Notice:

1. The time of the starting could not excessive fifteen minutes, and you must

stop two minutes if you want to continue starting. If it failed start by three times,

you should find the reason and get rid of it, then start it again.

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2. After the engine started, should loose the accelerator pedal, and supply right

amount of oil, keep the engine running properly. Check the oil pressure and cooling

water, if turbocharger has the abnormal noise and vibration, and water, oil, air have

leakage. After all these are ok, then keep on running with low and medium speed

for 3-5 minute, after coolant is heat up (generally it is 50℃above), then you can

start to run.

3. Cold engine is forbidden to run with big accelerator to avoid damage the

relative parts and speed up the wearing of the moving parts and so on. The time of

idling for turbocharger and turbocharger inter-cooled engine should not excessive

10 minutes.

D. Detail regulation for run-in maintenance

Regular maintenance is one of the important items to operate new engine

rationally, and make the different parts match well, so as to avoid the abnormal

damage and wear. Experience proves that engines service life, reliability and

economic depend largely on primary wear of the engine. Please customers must pay

attention to carry out the regulation of run-in maintenance. To the repaired engine

should perform the regulation to run-in.

The stipulation is the basis for DCD and its service stations to perform “run-in

maintenance” service. When the services stations performed its run-in maintenance

service, it must be registered and stamped, which is the basis for customers to

“guarantee service.”

1. Specification of engine run-in:

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(1). Run-in period:

Engine run-in is normally about 60 hours together with vehicle and if it

calculates by mileage, engine must be run-in for about 2,500 km.

(2). The load and speed required in run-in period:

Mileage(km) load speed

0~200 idle

>200~800 50% rated load 70% rated speed

>800~1500 70% rated load 75% rated speed

>1500~2500 75% rated load Not over the max. speed

2. Conditions in run-in maintenance

(1) Vehicle mileage is between 1,500~2,500 km.

(2) Diesel engine are surely not required or adjusted by the customer.

(3) If the mileage meter was damaged or failed on the vehicle, customer can

apply for run-in maintenance service to the nearest technical service center within

15 days (count from the second date when customers collect the vehicle or engine.)

3. Detail regulations of run-in maintenance

(1) When run-in operation finished, customer can apply for run-in

maintenance at nearest technical service center of DCD.

(2)When the service center found the engine meet the second term of run-in

maintenance, it can get the run-in maintenance service.

(3) When the run-in maintenance operation finished, the service center

should write down clearly item by item and give the maintenance sheet and

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certification with an official seal and customer stamp or personal signature on it to

the customer.

(4) According to Quality Warranty Manual of the vehicle about the

customers who bought the Dongfeng’s vehicle. To the others vehicle, invoice (copy

is ok) of the vehicle and duplicate of certification can be used as the certificate of

run-in maintenance and quality warranty for a new engine.

(5) If the mileage of a vehicle is over 2,500km (or over 15 days), but that

engine did not perform run-in maintenance, and once find fault on the engine, the

technical service center will not give “guarantee maintenance”.

4. The contents and standards.

No. Contents Standards 1 Change oil in the oil pan Chose specified diesel oil, select the

brand as per the ambient temperature 2 Change oil filter barrel Chose parts from formal suppliers 3 Clean air filter element and dust

plate

4 Change diesel filter barrel 5 Check the torque of head bolts 113~147N.m(11.5~15 kgf.m) 6 Check and adjust valve clearance Intake & exhaust clearance is 0.35mm 8 Check belts tension of the fan Apply 39N vertically on single belt

39N, deflection is 10~15mm 9 Check VE pump plunger lift According to Operation Manual 10 Tighten external bolt and nut According to the requirements 11 Check injector spray Injector pressure is 9.8MPa(100kgf/cm3) 12 Check the running of turbocharger Running flexibily and no seizure

E. Operation of diesel engine

In most cases, the change of engine, vehicle speed and load should be gradually,

avoiding sudden and instant step on paddle, except for few circumstances.

Constant attention is paid to the reading of all meters and engine operation

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conditions (noisy operation and exhaust smoke) during engines or vehicles in

operation, and emergency measures must be taken whenever engine operated

abnormally.

Water temperature is about 358K(85℃)when engine operated normally, oil

compression is about 196~490kPa (2-5kgf/cm2).

Vehicles with turbocharged-engine and turbocharged inter-cooling engine are

forbidden to apply the measure “speed-up ----- flameout-----idling-----put into gear

with clutch”. Because engine is flameout suddenly at high temperature and high

compression, at this time, oil pump and water pump all stop operating, so it can not

make lubrication and coolant take away heat of spares, especially super-charger,

except lubrication oil with lubrication, it has another important role which it can

cool internal spares of super-charger.

F. Stop of diesel engine

Speed and loading should be gradually reduced before engine stop. After engine

stopped, it should idle 3-5minutes, then to stop in order to make engine cool evenly

and gradually, so it can prevent damage spares because of engine is overheat.

Especially it is important for engine with super-charger. Because rotor of

super-charger belongs to the spare of high-speed, it can make bearing of rotor be

scarcity of oil, so it can not cool even to be damaged if stop engine suddenly.

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Chapter III Maintenance of Diesel Engine

Regular maintenance is one of the important items to operate engine rationally.

Therefore, careful maintenance can be performed under criterions if the customers

want to keep the engine in excellent working condition and serve reliably for long

term.

The maintenance criterions below are the content on limited maintenance period

and minimal operation worked out under engines good and normal condition. Our

customers may make any proper alternations according to local environment and

working conditions.

a) Routine maintenance

i. Checking lubrication oil in the pan, if it is not sufficient, it should be

refilled it. And finding out the cause when lubrication oil level rises and

reduces, to refill it to the set value.

ii. Checking the position of coolant, if it is not sufficient, to refill it.

iii. When does not use deicing liquid, cooling water should be drained out

when engines are placed in environment below 5℃.

iv. Checking the connection between super-charger and inlet and outlet

pipes, and whether fuel inlet oil and fuel outlet systems are leakage, and

whether the pipes between air filter and inlet compressor of

super-charger and adapter are well to super-engine. If these are abnormal,

we should get rid of it in time.

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v. If the engine is leakage oil and coolant, if it existed the cases, we should

get rid of it.

vi. Keeping engine clean and necessary wash is required.

vii. Getting rid of all troubles and abnormal phenomena.

B. The maintenance after 2,000 km. (accumulative 50 hours in operation).

1. Complete the items and contents of routine maintenance.

2. Checking all external bolts, nuts and accessories and tight it by torque.

3. Checking the tension of fan, if it is necessary to adjust.

4. Changing the spin-on one time used oil filter barrel when maintenance is

done every 8,000-10,000km.

5. Cleaning the dust in air filter disk. If the air filter element was damaged, it

should be changed.

C. The maintenance after 8,000 km. (accumulative 200 hours in operation).

1. Complete the items and contents of the maintenance after 2,000 km.

2. Checking injection compression and spraying of injector, and cleaning

and adjusting necessarily. And check and adjust speed of idling.

3. To check value of injection pump plunger, and if it is over to adjust it, and

according to the requirement to discharge pump.

4. Checking and adjusting valve gap.

5. Cleaning oil pan and oil suction screen.

6.Replace the element of primary fuel filter every 12,000~16,000km.

7. Cleaning air filter elements and its dust receiver.

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8. Cleaning fuel tank, fuel lines.

9. Blowing away the dust inside of alternator and starter by compressed air,

lubricate the bearing and checking whether all parts are ok.

10. If it is necessary to check working of rotor, dial the rotor with hand. If it

rotated steadily and rotated freely above one circle, we looked it normal,

or dismantle its inside. Here we must notice, when we checked the

working of rotor, we must keep around position and outside surroundings

where we dismantled are clean. And to prevent impurity falling into

supercharge system when we install it again, or it causes serious result.

In addition, in normal case, assemble or dismantle turbocharger

assembly with special tools. Generally, only manufacturer of

turbocharger and service station can have this condition. Please don’t

assemble and dismantle.

D. The maintenance after 45,000 km. (accumulative 1,000 hours in operation).

1. Complete the items and contents of the maintenance after 8,000 km.

2. To clean cooling system.

3. To clean oil filter element.

4. To change air filter element, when it was continuously been

maintenance for five times or used one year.

5. According to necessary, to change seal sleeve of valve.

6. Checking the bolts on cylinder head, connect rod and main bearing,

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then to tighten the loose ones till their set value are met.

7. Checking water pump internal seals and refilling fresh grease.

8. Removing and checking electric generator and starter, cleaning

maintenance them and refilling grease.

9. Removing and maintenance of cylinder head and regrinding valve are

usually decided according to working condition.

10. Adjustment of injection pump is usually decided according to

working condition.

11. Base on situation to decide whether it’s necessary to check oil pump

delivery and pressure limited valve behavior.

12. To dismantle and check super-charge assembly according to the

necessary, and change easy damage parts.

E. Judgment of diesel engine overhaul

1. Rate of increase about oil consumption:

We supposed that new vehicle mile of running per liter oil or hours is

100%. When it reduced 50%, it should be repaired.

2. Rate of increase about fuel consumption:

We supposed new vehicle mile of running per liter oil or hours is 100%.

When it reduced 60%, it should be repaired.

3. Existing noise inside

There are all kinds of reasons to noise, if it belongs to serious wearing

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and overheat, or operation and maintenance is not right, we must carry

out main repairing.

F. Maintenance of winter operation

Engine must be specially cared when operate at below 5℃.

1.Winter engine oil and fuel must be used to engines and special attention

must be paid to water content in fuel to avoid fuel circuit block.

2. Deicing liquid had better filled into cooling system, or cooling must be

drained when the water temperature fall down to 40~50 ℃ after engine

has stopped.

3. Vehicles should not be put in the open in winter, or cooling water and

engine oil must be heated to preheat the engines when starting. Soon after

all this has been prepared , engine may start without much difficulties at

environmental temperature -35℃.

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Chapter IV Regular Adjustment of Diesel Engine

A. Adjustment of valve gap

To adjust gap of valve according to the following ways, and we use valve

gauge with engine.

To rotate crankshaft according to rotation direction of engine, set the top

center mark on the damper pulley to meet exactly the point on gear box,

the first and fourth cylinder piston are in the position of compression top

dead center, and rocker of the first cylinder intake and exhaust valve with

hand from up to down, if both of them exist gap, it proves that piston of

the first cylinder is in the position of compression top dead center. If both

of them do not exist gap, but arm of intake and exhaust valve of the fourth

cylinder exist gap, it proves that the piston of the fourth cylinder is in the

position of compression dead center.

Finishing adjustment of valve gap in two times: 1 2 3 4 No. cylinder

Valve N0. of cylinder in Compression T.D.C

IN EXH IN EXH IN EXH IN EXH

1 O 0 0 0 4 * * * *

Remark: 0—It means when the first cylinder is in the position of

compression top dead center, and it should be adjusted valve gap.

*------It means when cylinder no.4 is in the position of compression top

dead center, and it should be adjusted valve gap.

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B. Belt of fan

To apply 39N to the single belt in the middle position between two wheels,

its deflection is 10~15mm, or it should be adjusted.

C. The opening pressure and spraying quality of injector

The injector is installed on the test stand, and move handle at

4~6times/second. To check if there are particles flying out and abnormal

spray ect. To keep injection compression is below 9.8Mpa, and there is no

leakage, it proved it is good.

The opening pressure of injector is 9.8Mpa, and if it is abnormal, it should

be repaired or changed injector couple.

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Chapter V Main Parts of Diesel Engine

A. Cylinder block group

Engine block is an integral casting of crankshaft case and cylinders, in which

full-support main bearings are used, and it is made of alloy casting iron. No

cylinder liners are used, and the bore diameter is 99.200~99.230. All main

oil-gallery, main bearing-bore, camshaft bore, plunger bore and all interfaces should

be kept clean before cylinder block is mounted, and should keep oil passage

unblocked. There is dipstick on the left side of the engine block where the oil level

should be always laid between two scales.

Water drain valve is on the rear-left. Change cooling of the engine: Open the

water drain valve, and drain cooling, then close water drain valve of engine and

water tank, fill water, heat engine, then stop engine. Repeat to do this for 2-3 times.

Adopted floated double oil sump, the screws tightening starts from center to

either side alternatively with proper tighten torque to avoid oil pan deformation.

When the drain plug is leakage, we should check if the gasket is perfect or not.

Tightening the drain plug with excessive torque will make the thread loose.

B. Cylinder head group

The cylinder head is a four-cylinder unit, made of alloy cast iron. There is a

cylinder head cover, on which is an oil filler. Cylinder block gasket was divided into

three groups to assemble, and piston gap must be measured which value is 0.8~1.1

when new gasket is replaced.

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Before assembly of cylinder head 20g luboil should be applied uniformly into

internal circumference of each cylinder. Then cylinder head and block can be fixed

with locating bushes and connected with bolts and screws with tightening torque

from 39-44N.m at first and then tighten them from 64-69N.m, the third tighten from

90º±10º.

Tighten them to reach set value in sequence as follow:

15 7 6 14

16 8 1 5 13

I Ⅱ Ⅲ Ⅳ

17 9 2 4 12

18 10 3 11

C. Crankshaft and flywheel assembly

Clearance of crankshaft is 0.06-0.25mm.and main bearing is 10 pieces in two

different kinds. Keeping bearing backs oil-free to avoid affection of heat dissipation

when assemble bearings. Thrust washer is installed on the fourth bearing seat and

positioned by the upper and lower thrust washer extended tail, keeping the working

surface (the side oil groove) towards crank-web.

Closed attention to clean crankshaft before it was mounted into cylinder, and

especially attention to the cleaning of journal surface, oil gallery port and bearing

seat surface. If main bearing shell with oil hole was mounted on the bearing seat, it

should be coincidence with oil hole.

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The combining machining of main bearing caps and engine block are marked

with numbers and serial numbers on the caps. The fourth bearing cap is positioned

by bush. The rest bearings are positioned by lugs. The tip of triangle mark of caps is

facing the front of engine block and numbered beginning from the front when

assemble them.

The main bearing bolt is lubricated with diesel oil, and alternatively tighten

them from the center towards the two sides and when it is done, the crankshaft can

rotated smoothly.

At the rear of crankshaft is flywheel, and it is positioned by lugs. When it is

tightened, sequenced according to diagonal line alternatively. The swing error

allowance of the rear of flywheel is below 0.2mm. There is a damper in front of

crankshaft with three slots pulley. Screws of crankshaft nut should coat grease of

molybdenum disulfide, and nut chamfer is tightened facing to the outside.

Crankshaft, flywheel and crankshaft damping pulley have given dynamic

balance, please pay attention to its balance when changing parts.

D. Piston and connecting rod group

The piston is with two compression rings and one oil ring. The first and second

are compressed rings, and the oil ring is coiled spring expender. When assembly

pistons and connected rods, the arrow pointing direction of the piston should face

the front of engine block (the end of fan). The piston ring open is the same with

axial direction of piston pin and separately difference is 180º. The position should

31

stagger 180℃ with oil ring open which spring is connected with steel wire inside

oil ring. Special expander should be used when piston ring is assembled to avoid

over expending or it may be broken. The ring should be rotated freely in groove and

fallen freely into bottom of the groove by gravity.

The connecting rod body are numbered on its caps in order to avoid errors and

mistakes in directions. When assembled bearing shell, the working face should be

coated oil, but shell back should not coated oil, or it will effect heat dissipation.

Connecting of piston pin and connecting rod adopted full floating. Pistons must be

heated to 60-~80℃ when piston pins are assembled.

The weight of big and small ends of connecting rod are strictly controlled and

assembly weight deviation is below 8g and connecting rod assembly (don’t include

connected shell) mass deviation is below 3g, pistons are chosen the same mass to

compose one group, this must be closed attention when replaced the parts.

E. Transmission system

Valve transmission system adopted side camshaft driving structure. Vale

leakage will affect technical state of the diesel engine, even causing valve and seat

burning, during using we must check sealing state according to the requirements

and practice. Valve lapping has to be done if necessary. Distinguishing rocker by

writing words and mark. Rocker arm, rocker arm shaft, rocker seat and valve

assemble must be cleaned when they were assembled. And after assembled its

movement should rotates freely without any objection, and plugs of two ends of

rocker arm should seal well. Valve springs should adopt unequal matrix spring, and

32

when we inserted them, the side of the mark should be down.

Adopting timing gear of high engagement, gear rotating is shown following:

Fuel injection pump gear idler gear camshaft gear

Vacuum pump gear crankshaft gear oil pump gear

The timing marks on gear surface must be correctly set when gears are

assembled, in order to ensure correctly air and fuel supply. Screws and bolts should

be firmly tightened and every gear rotates freely without any objection.

33

Chapter Ⅵ Supply System of Diesel Engine

A. Diesel engine combustion and combustion chamber

Ignition method of the diesel engine is compression ignition, the type engine

adopted swirl combustion chamber, and the compression is 22:1.

The swirl combustion chamber is consists of swirl chamber and main

combustion chamber. The swirl chamber is on the top of cylinder head, there is a

tangent passage through the main combustion chamber. When compress the stroke,

the air pressed into the swirl chamber generates strong swirl movement, promote

the injected fuel to be mixed with the air. The mixture flows into the main

combustion chamber after firing, forms the second flow, have a further mixing and

burning with the air inside the main combustion chamber. A supplementary needle

type of injector is used in swirl chamber and combustion chamber, the injection

pressure is lower, working is reliable. The advantages are soft in working, low in

noise, air utility is higher and injection pressure is also lower

The engine imported mature technology of Nissan Diesel Japan, making the

match of inlet system, supplying oil system and combustion system keep wonderful

state, so the targets of power, economy, emission and noise are very good.

B. Exhaust gas recirculation system (EGR)

CRQD32EGRdiesel engine is using EGR technology. EGR system is also call

exhaust gas recirculation system, the main function is: allow the partial exhaust gas

34

comes from the exhaust outlet of the head to recirculate and return to the intake

manifold, enters the combustion chamber together with the mixed gas to reduce the

burning temperature, hence reduce the resultant of NOx, finally reduce the

atmosphere pollution. By using EGR technology, the Nox emission has effectively

reduced, meanwhile, by means of good matching with injection system and burning

system, improves burning, increases power, lower fuel consumption, improves the

emission of other exhaust gas, fulfill the requirement of national emission

regulation.

C. Turbocharge system

CYQD32T diesel engine was adopted exhaust turbo-charging technology. And

turbocharge is the important method for increasing power, improving economy and

reducing exhaust pollution without adding displacement and speed of diesel and is

also the development trend of diesel engine at present.

Exhaust turbo-charger used exhaust energy by diesel exhausting with

temperature and compression and rotary mechanical by turbo-charge change into

rotator. So it made blade of the same axle compressor rotate highly, after it make

fresh air increased compress and raised density, cooled by inter-cooler, entered

cylinder by inlet pipe, and it increased filling air, so it can inject the more diesel and

increase power of the diesel engine.

In altitude, because of low air pressure, thin air and hypoxia, power of

naturally aspirated engine will be reduced, in general it will reduce about 10% per

35

1000m, but adopted turbo-charge engine, increasing of altitude of water surface

affected very small to power. Because turbo-charger will increase with increasing of

altitude of water surface, and speed will increase too. So increased turbo-charge

compression, it may compensate inlet density because of increasing of altitude of

water surface, then it will reduce fall of engine power. In general, power will only

reduce 3% per 1000m. So adopting turbo-charge is the best way that restores power

of altitude.

The intake (connected to the end of air filter) resistance from the end of

turbocharger compressor and the exhaust resistance (connected to silencer) from the

end of turbocharger turbine have bigger influence to the engine performance. When

the intake resistance is too big, it’s easy to cause insufficient intake quantity of

engine, hence the engine will have black smoke, exhaust temperature is high, the

power of the engine will be reduced and oil leaking in turbocharger, etc. In order to

ensure the engine is under normal working state, the requirement is as following:

1. When using the new air filter, the intake (connected to the end of air

filter) resistance from the end of turbocharger compressor is < 3Kpa

2. When using the old air filter, the intake (connected to the end of air filter)

resistance from the end of turbocharger compressor is < 6Kpa

3. The exhaust resistance (connected to silencer) from the end of

turbocharger turbine is < 3Kpa

36

Working Principle Diagram of Turbocharger

D. Turbo-charge inter- cooled system

CYQD32 Ti diesel engine adopted super-charged inter-cooled technology.

Exhaust turbo-charger used exhaust energy by diesel exhausting with temperature

and compression and rotary mechanical by turbo-charge change into rotator. SO it

made blade of the same axle compressor rotate highly, after it make fresh increased

compress and raised density, cooled by inter-cooler, entered cylinder by inlet pipe,

and it increased filling air, so it can inject the more diesel and increase power of the

diesel engine.

Supercharged hot air by supercharger entered inter-cooled, made air cool and

reach right temperature, then entering cylinder by inlet pipe. After adopted

inter-cooled technology increased inlet density, reduced inlet temperature, thus may

increase inlet air, and well matching by injection oil system, combustion system, so

37

it improved combustion, and increased the power of diesel engine, and reduced

consumption, and improved pollution. During using, you must pay attention to

avoid touching inter-cooler, and keep connection pipe sealing, in order to avoid

affecting performance of diesel engine. Notice must not make turbo-charged

inter-cooled diesel as non-turbocharged diesel engine used.

E. Fuel supply system

The low pressure part of dividing pump fuel system is consists of fuel tank, low

pressure pipe, fuel water separator with hand supply pump, fuel filter, vane supply

pump, inner pressure control valve and fuel return screw (of which fuel tank, fuel

water separator with hand supply pump, fuel filter are not parts supplied with the

engine). The vane supply pump sucks fuel from the fuel tank, every rotation will

delivery constant amount of fuel to the injection pump. The inner pressure control

valve allows the inner pressure versus speed of the supply pump. The inner pressure

of the pump and the speed is increasing proportionally (the higher of the pump

speed, the higher of the pump pressure will be).

Some fuel returns to the suction port through the inner pressure control valve,

there is also some fuel flow back the fuel tank through “return fuel screw”, the

purpose is cooling and self-exhaust of injection pump.

In order to let the injection pump working effectively, the supplied fuel must

have certain pressure, no bubble and supply continuously. If the height difference

between fuel tank and injection pump is too big, or the pipe between fuel tank and

38

injection pump is too long, then it’s necessary to install a front supply pump, thus

can overcome the resistance between fuel pipe and fuel filter.

The manufacture accuracy of the high pressure part of injection pump and

nozzle is only a few micro, so the substance in the fuel will cause failure,

insufficient filtering will damage the parts of injection pump, delivery valve and

nozzle. The fuel filter must be specially made as per the requirement of fuel system.

Strongly suggest to use the fuel filter recommended by Dongfeng Chaoyang Diesel

Co., Ltd. when customer use or change the fuel filter.

Fuel may contain restrained water (emulsification) and unrestrained water. If

the fuel contains water go into the injection pump, it will cause corrosive damage.

Therefore, a fuel filter with reservoir or separate fuel water separator must be

installed before the dividing pump so as to drain the filtered water regularly.

1.Fuel pump

CYQD32 CYQD32EGR CYQD32T CYQD32Ti Type Distribution Bosch VE pump Injection order 1-3-4-2 Plunger diameter (mm)

11

Cam lift 2.8 Plunger lift standard When check: ±0.05

When adjust:±0.02

0.416

0.468

0.527

0.736

Injection time increase and decrease device

Oil pressure

Fuel cut-off mode Electromagnetic Start advance angle

control device (electromagnetic)

Yes (model in cold area)

Fuel injection adjusting

Centrifugal mechanic governor

39

2. Injector

Using axial needle nozzle, the working principle of it is same as hole

nozzle. Under the sealing cone at the low end of needle valve has another extended

axial needle, it extends outside of the injection hole, allow the injection hole

become a round narrow seam. There is only one hole in the injector with diameter

1mm. The injection pressure is lower, reduced noise and increased power at the

same time.

Characteristics of axial needle nozzle:

2. The needle valve closes the hole when on injection, which keeps

high pressure fuel chamber apart from the combustion chamber, so

the burning gas will not rush into the fuel chamber and causes block

up by accumulate charcoal.

3. The diameter of the injection hole is bigger, which is easy for

machining and no plugged.

4. The needle valve will open when the fuel pressure reach certain

pressure, when stop fuel supply, it will close at once under the

function of spring, therefore, injection start and stop are all quick

and agile, no fuel dropping.

The specification and target of injector for CYQD32 series diesel engine

are as followings:

connection way of nozzle Thread connection

Nozzle type NP—DNOPDN121

40

Nozzle numbers X diameter 1 x 1.0

Injection pressure MPa (kgf/cm2) 9.8 (100)

3. Fuel filter

Using the best filter with resin coat and antirust. Clean or change the element of

fuel filter in time, change all sealing parts when necessary. When the engine is used

in cold area, use the fuel filter with fuel return control valve.

4. High pressure pipe

Inner diameter X Out diameter X Length = ф2mm X ф6mm X 498

Operation mechanism of VE pump for CYQD32 diesel engine

41

5. Governing characteristic curve and injection quantity adjusting data of

injection pump of CYQD32 series diesel engine

Speed of injection pump (r/min)

Governing characteristic curve of injection pump CYQD32, CYQD32EGR diesel engine

Speed of injection pump

(r/min) Governing characteristic curve of injection pump

CYQD32T diesel engine

42

Speed of injection pump

(r/min) Governing characteristic curve of injection pump

CYQD32Ti diesel engine

Injection quantity adjusting table of CYQD32 series diesel engine Model Adjusting point Pump

speed r/min

Average fuel supply mll/1000st

No average Quantity ml/1000st

Fuel temp.

Rated point 1800 52.7±3.5 Max.torque point 1000 50.7±1.0 4.5 Idle point 350 10.9±2.5 2.0

CYQD32

Max.dry running point 2350 19.2±2.5 Rated point 1800 54.3±3.5 Max. torque point 1000 54.3±0.5 4.5 Idle point 350 10.9±2.5 2.0

CYQD32 EGR

Max.dry running point 2350 19.2±2.5 Rated point 1800 64.7±4.0 48~52 Max. torque point 1000 56.8±1.0 6.0 48~52 Idle point 350 10.3±2.5 2.5 46~50

CYQD32T

Max.dry running point 2350 24.6±2.5 50~54 Rated point 1800 75.3±4.0 48~52 Max. torque point 1000 70.9±1.0 6.0 48~52 Idle point 350 10.3±2.5 2.5 46~50

CYQD32Ti

Max.dry running point 2350 30.1±2.5 50~54

43

Chapter Ⅶ Auxiliary System of Diesel Engine

A. Lubrication system

Lubrication system diagram is as following:

----------------------- --- - - ----------------------------------------- oil passage

------ by passage main oil gallery -..-..-.. through oil sump

------- -------------------------------------------

Oil sump

Filter oil screen

Oil pump

Oil filter

Oil cooler

Safe valve

By—pass valve

By pass valve

Equalizer

valve

Main oilgallery idler

Main bearing

crankshaft

Connecting rodbearing

timing gear Piston

Cooling injector

Camshaft bearing

tappet

Push rod

Cylinder head

Rocker seat

Rocker arm shaft

rocker

Vacuum-pump

44

Lubrication system maintenance:

The oil level in oil pan must be checked before engine starting. The oil level

must be within the two marks of oil dipstick. The changing and cleaning of oil and

filter element is done according to the requirements.

The maintenance of lubrication system is done timely, and the more

thoroughly the better, because it may help our customers to use engine reliably and

to operation in long term with satisfactory.

Close attention must be paid to pressure gauge during operation, the oil

pressure is 196~490kPa (2~5kgf/cm2) in normal operation, and over 98 kPa

(1kgf/cm2) in idling operation.

B. Cooling system

The closing system is close forced circulation water cooling type. Water

temperature in cooling system is kept about 85℃.Low temperature will lead to

wear of engine. High temperature will lead to be abnormal operation or failures.

1. Flow direction of coolant:

Water flows out from water pump outlet to the right side of engine block, cools

the oil cooler at first then flows into cylinder water jacket and cylinder head, from

there goes into the thermostat installed in the front of cylinder head. The holes of

cooling water in cylinder head and engine block are made casting and drilling.

Some holes are small, therefore close attention must be paid to be restricted,

especially care to the cooling water jet for cooling the triangle area among valves

45

and nozzle, or it leads to overheat in this area and damage the fuel injector.

Therefore, we especially recommend our customer to use long-term effective

coolant, otherwise it may cause troubles.

2. Water pump is centrifugal type:

When water seals break down, coolant will leak from the overflow hole, so it

must be repaired timely.

3. Thermostat

The opening temperature of thermostat is 76.5℃. When the thermostat is

closed, it makes a small cycle and the water coming out from the cylinder head will

all flow back into the water pump. When water temperature reaches or rises 90℃,

makes a big cycle, all water flows into radiator and cools there. Thermostat cannot

be removed under any condition.

4. Cooling system maintenance:

In normal operation, must use long-term effective coolant. Besides, if found

leakage in cooling system, please clean it as per the following method:

Clean agent was made by mixing 150g sodium hydroxide ( NaOH) with 1 liter

water. Before cleaning, drain out the coolant from the cooling system first, then

pour into the equal cleaning agent, stay 8~12 hours, then make engine operation.

After the temperature reached the working temperature, stop the engine and drain

46

out cleaning agent immediately in order to avoid floating scale deposited there, at

last clean cooling system with cleaning water.

Checking the water level in radiator every time before vehicle is in operation or

go back the parking place, refilling to the specified level when it’s insufficient.

Checking and maintaining the belt tension of the water pump regularly, which is

adjusted by alternator bracket and tensioner. When the belt is pressed by 29~39N

(3~4kgf) force, the deflection of single belt should be between 10~15 mm, neither

too tight nor too loose.

5. Silicone oil fan clutch:

CYQD32 series diesel engine is using silicone oil fan clutch. The silicone oil

fan clutch is installed between driving shaft and fan. You can base on the

requirement of engine cooling system, control the speed of fan and adjust the

strength of cooling. Compared with conventional rigid fixed fan, the main

advantages of the cooling system with silicone oil fan clutch are as followings: save

energy, reduce noise, low emission and less wear etc.

CYQD32 series diesel engine is integrated water pump with clutch, the basic

contour is shown as figure. The water

pump and clutch are fixed on a driving

shaft, as a complete part, the advantages

are: proper in space layout, less run-out

in concentric，good in dynamic balance,

long service life.

47

C: Auxiliary system

1. Vacuum pump

Vacuum pump is driven by injection pump gear directly.

Flow rate of vacuum pump (cm3/rev) 60

Gear number of vacuum pump 39

Negative pressure when idling (reference)

kpa(mmHg)

-87 (-650) above

2. Starter:

Use starter with two axial decrease speed:

Model S14-205

Power 12 V-2.8 kW

3. Alternator:

The standard setup rated output: 12V, 70A. On request, it also can use alternator

with 14V, 90A or 14V, 120A .

D. Clutch

The engine can match clutch with friction disc diameter of ф260mm orф

275mm according to the customer’s requirement. The engine doesn’t equip with

48

gearbox and operation mechanism. The clutch is only given a preliminary

adjustment before delivery, customer needs to readjust it when it is installed in

vehicle or in operation.

E. Preheating device

There is a preheating device in the engine, the heating part of the glow plug

heats the air by penetrating into the pre-combustion chamber, hence ensure the

diesel engine start smoothly under lower temperature.

A. Instruction of glow plug

1. The rated voltage of glow plug: dc 11±0.1V, the working voltage of

glow plug must be same as the voltage of accumulator.

2. Current characteristic of glow plug: under rated voltage, the working

current of glow plug after electrified for 20S should be ≤10A, the

sustained working current (60S) should be ≤8A.

3. When connecting end of the glow plug is wired, the tighten torque of

the nut is ≤7N.m.

4. The preheating time is more than 20 seconds and less than 60 seconds,

it will influence the service life of glow plug assembly if the heating

time is too long.

5. Change the glow plug assembly in time in case the head of it was

damaged, otherwise, it’s easy to cause short circuit of it.

6. Prevent electric conducting plate from contact with the nearby object,

to avoid burning electric system because of short circuit.

49

B. Instruction of preheating device:

The preheating device consists 4 glow plugs, 1 electric conducting plate, 1

wiring harness and 1 preheating electronic control accompanied with the

engine. According to the different requirement of vehicle setup, the

working principle of the preheating electronic control accompanied with

the engine and the type of insert parts are also different, generally there

are two kinds of them:

One is a wiring diagram of the preheating electronic control, type DKK

1507, shown as below figure. This preheating electronic control is used

with electronic fan, it has low speed relay and high speed relay. The

setting temperature of low speed and high speed relays correspond with

the operation temperature of low speed and high speed fan.

Wiring Diagram

50

1. Please connect the wire strictly follow the wiring diagram, especially

pay attention to the connection of positive/negative power supply,

otherwise, the electronic device can’t work properly and may be

damaged due to this reason.

2. When starts the engine, the preheating lamp start to light after the key

switch is turned on .The engine can start only the preheating lamp is

off. If the key switch is turned to Start position, but the engine still

doesn’t start within 15±3 seconds, the electronic device will cut off

the circuit automatically; If want to start again with preheating, then

must turn off the key switch for about 3 seconds, then repeat the above

procedure.

3. During post preheating, the low speed relay will be on if the coolant

temperature is above 86℃; the high speed relay will be on if the

coolant temperature is above 93℃.

4. In order to protect your engine and benefit, in cold whether, we

strongly recommend to start the engine only when the front preheating

lamp is off.

5. Note: must use a post preheating glow plug that matching this device.

The function of every pin in below DJ7121 y-2.2-20 connectors are as

following:

51

Match DJ7121 y-2.2-20 connectors

1. Connect to start shift of key switch (ST)

2. Connect to D + signal

3. Connect to preheating indicating lamp

4. Connect to the negative pole of accumulator

5. Connect to temperature sensor

6. Connect to vehicle speed sensor

7. Connect to working shift of the key switch (ON)

8. Connect to preheating relay of glow plug (matching with 70A/14VDC)

9. No connection

10. Connect to low speed relay

11. Connect to high speed relay

12. Connect to overflow valve (KSB valve)

Another type is a preheating electronic control that matching with normal fan,

such preheating electronic control has no low speed relay and high speed relay.

Note:

1. The way of connection and connector type for different type of preheating

electronic control may different.

2. In order to avoid improper working of the preheating electronic control,

when customer change temperature sensor and vehicle speed sensor, please

chose the same product from the same manufacturer that same as original

one.

52

F. Idling increasing device

A idling increasing control and its control electromagnetic valve are installed on

injection pump of the engine. The function of an idling increasing control is:

when turn on air condition when engine is under idling mode (700 ± 50r/min),

the electromagnetic valve of the idling increasing control is in operation, pull the

fuel filling handle move a certain distance torwards fuel filling direction, allow

the idle of engine increased to 850 ± 50r/min in order to increase the

generated energy of the alternator to fulfill the requirement of air condition.

Idling increasing device

53

Chapter Ⅷ Trouble and shooting of Diesel Engine

A. Difficult to Start

1.Starter Doesn’t Run

Mainly Check Reasons Remedy

Starting switch NG→ poor contact, damage → repair, replace ok↓ fuse NG→ melt → replace ok↓ storage battery NG→ poor contact caused by ↓ terminal loose, corrosion→ clean and tight

↓ NG→ not full charged, poor discharge→ repair charging system charge or replace

ok↓ NG→ fan belt loose, damage → tension, replace starter NG→ poor magnetic switch → repair and replace NG→ poor starter → repair and replace

2.Starter Runs But Engine Doesn’t Run

storage battery NG→ poor contact caused by ↓ terminal loose, corrosion→ clean and tight ↓ NG→ not full charged, poor discharge→ repair charging system

charge or replace ↓ NG→ fan belt loose, damage

( influence the alternator) → tension, replace ok↓ starter NG→ small gear or gear ring damaged→ replace ↓ NG→ brush worn, brush spring broken→ clean and tight ↓ NG→ magnetic switch damaged → repair, replace ok↓

engine itself NG→ internal moving parts damaged, melt, such as piston, main shell→ repair, replace

54

3. Starter Runs But Engine Doesn’t Work * Injection Pump Stop to Supply Mainly Check Reasons Remedy

Engine stop whether the solenoid valve of injection mechanism NG→ pump is connected to the power supply→ check & adjusting ok↓ fuel tank NG→ no fuel → filling ok↓ fuel pipe NG→ blocked, damaged, loose in connection part → repair, replace

and tight ok↓ fuel filter NG→ overflow valve can’t close→ repair, replace ↓ NG→ filter element blocked → replace ok↓ fuel system NG→ mixed with air in fuel system→ release air NG→ inlet screen blocked in Fuel supply pump → clean and repair

NG→ fuel supply pump doesn’t Work properly → repair, replace * Injection pump supply fuel

Fuel NG→ poor quality or incorrect brand→ replace ↓ NG→ water in fuel → replace

ok↓ fuel system NG→ air in fuel system → release air ok↓ advance angle NG→ incorrect advance angle → adjusting ok↓

injector NG→ injector assembly blocked leaking → replace ↓ NG→ opening pressure is low → adjust and replace

ok↓ injection pump NG→ poor delivery valve, blocked→ repair, replace ↓ NG→ plunger worn or blocked → repair, replace ok↓

compressed pressure NG→ cylinder bore worn, piston ring blocked or broken → repair, replace NG→ valve leaking → repair, replace

55

B.Idle Speed Is Unstable Mainly Check Reasons Remedy

Fuel system NG→ leaking in fuel system → repair, replace ↓ NG→ mixed with in fuel system → release air ↓ NG→ water in fuel → replace

ok↓ fuel filter NG→ filter element blocked → clean, replace ok↓ injector NG→ injector assembly blocked, leak→ adjust, replace ↓NG→ opening pressure low, poor injection→ adjust, replace ok↓ fuel pump NG→ idle speed is too low → adjust, replace

↓ NG→ oil is uneven in each cylinder → adjust, repair ,replace ↓ NG→ poor delivery valve, blocked → adjust, repair, replace ↓ NG→ plunger worn and its spring broken→ replace ↓ NG→ camshaft worn, tappet worn → replace

ok↓ engine itself NG→ valve gap incorrect → adjusting ↓ NG→ poor valve and valve seat seal → repair, replace ↓ NG→ cylinder bore worn, piston ring

blocked or broken → repair, replace

C. Insufficient Power

Air filter NG→ filter element blocked → clean and replace

ok↓ fuel system NG→ mixed air in fuel system → release air ↓ NG→ oil circuit blocked → clean, repair, replace

ok↓ oil gate mechanism NG→ the lever is not in position

fuel supply is insufficient → adjust, repair ok↓

advance angle NG→ advance angle is incorrect → adjusting ok↓

fuel pump→NG main spring of governor adjust, replace ↓ NG→ plunger, camshaft or tappet worn→ replace

ok↓ turbocharger NG→ gas guide pipe of boost compensator

crack → repair, replace

56

↓ NG→ too much dirt in intake/exhaust manifold or leak air in connection → clean, repair, replace ↓ NG→ performance of turbocharger reduced→ clean, repair, replace

inter-cooler NG→ leak in pipe, dirt cause big resistance → repair, replace ok↓

injector NG→ poor spray of injector or blocked → adjust, replace ok↓

engine itself NG→ valve gap is incorrect → adjust ↓ NG→ poor sealing in valve, valve seat → repair, replace ↓ NG→ cylinder bore worn, piston ring blocked

or broken → repair, replace ↓ NG→ the gasket of the head is breakdown→ replace

D. Fuel Consumption Is Big

Fuel system NG→ leaking in fuel system → repair, replace

ok↓ air filter NG→ filter element blocked → clean, replace

ok↓ advance angle NG→ advance angle is incorrect → adjusting ok↓ injector NG→ poor spray of injector → adjust, replace ok↓ turbocharger NG→ too mush dirt in intake/exhaust

manifold or leak air in connection→ repair, replace ↓ NG→ poor performance of turbocharger→ clean, adjust, replace

ok↓ engine itself NG→ valve gap is incorrect → repair, replace ↓ NG→ not well sealed in valve, valve seat → adjust, replace ↓ NG→ valve spring became soft → replace ↓ NG→ cylinder bore worn, piston ring blocked

or broken → repair, replace

E. Oil Consumption Is Big Mainly Check Reasons Remedy

57

turbocharger NG→ failure of turbine end sealing or compressor blade end sealing → repair, replace

ok↓ valve seal NG→ failure of valve guide seal → repair, replace

ok↓ in/ex. Valve NG→ valve stem and guide is worn→ replace

ok↓ bore, ring NG→ cylinder bore worn, piston ring blocked

or broken → repair, replace ok↓

whole oil system NG→ leaking → repair, replace

F. Water Temperature Is High in Engine Outlet Cooling water tank NG→ coolant is not enough → filling ↓ NG→ radiator is blocked → clean ↓ NG→ cover of water tank damaged→ repair, replace

ok↓ water tank meter

or water tem. sensor NG→ failure → repair, replace ok↓

fan belt NG→ loose or damaged → tension, replace ok↓

water pump NG→ water pump damaged → repair, replace ↓ NG→ silicone oil clutch failed → repair, replace ok↓ thermostat NG→ failure, damaged → replace ok↓ seal between head and block NG→ gasket failure, water flow→ replace ok↓ cooling passage NG→ too mush scale, blocked → remove ok↓ advance angle NG→ too small, seriously rear fire→ adjusting

G. White Smoke in Exhaust Mainly Check Reasons Remedy

58

advance angle NG→ too small, seriously rear fire→ adjusting

ok↓ fuel NG→ water n fuel → replace ok↓

injector NG→ poor spray of injector, leak → adjust, repair, replace ok↓

turbocharger NG→ turbocharger damaged → repair, replace ok↓ in/ex. valve NG→ valve worn or damaged → replace ↓ NG→ failure of guide seal → replace ok↓ bore, ring NG→ cylinder bore worn, piston ring blocked or broken → replace

H. Black Smoke in Exhaust

Air filter NG→ filter element blocked → clean, replace ok↓ advance angle NG→ too big or too small → adjusting ok↓ injector NG→ poor spray of injector, leak → adjust, repair, replace ↓ NG→ opening pressure is low of it→ adjust, replace

ok↓ turbocharger NG→ doesn’t work properly → check, repair, replace

I. Oil Pressure Is Low

Mainly Check Reasons Remedy

Oil manometer or pressure sensor NG→ damaged → replace ok↓ oil NG→ oil brand is not correct → replace

ok↓ oil filter NG→ filter element blocked → replace ok↓

59

safety valve/ bypass valve NG→ spring damaged or valve

body blocked → repair, replace ok↓

oil pump NG→ gear was worn → replace ok↓ rocker shaft NG→ rocker shaft was worn → replace ok↓ camshaft &bush NG→ they were worn → replace

ok↓ crankshaft, con’rod and shell NG→ they were worn → replace

ok↓ oil cooler NG→ cooler element blocked → clean, replace

↓ NG→ opening pressure of the bypass valve is incorrect→ check,, adjust, replace

J. Failure caused by Turbocharger

1. Power is insufficient

* Black Smoke in Exhaust

Mainly Check Reasons Remedy

Turbocharger speed Is insufficient NG→ impurity of oil piled up at side

Seal of turbine → replace oil, repair turbocharger ↓ NG→ oil tem. is too high, oil is insufficient floating bearing burnt → check oil system, repair

turbocharger ↓ NG→ rotor of turbine shaft is out of balance→ repair, replace

ok↓ friction between turbine blade and compressor blade, damaged NG→ turbine speed is too high → check boost system, repair

↓ NG→ exhaust tem., pressure is too high→ check engine, repair ↓ NG→ mixed with foreign matter → check intake system, repair, replace

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↓ NG→ floating bearing was worn → replace

* White Smoke in Exhaust

Oil return pipe Of turbocharger NG→ oil leaks from turbine and compressor Shaft end caused by block and deform.→ repair, replace

ok↓ seal ring NG→ damaged → replace

2. Oil Consumption is Too Big seal ring NG→ worn, damaged → replace ok↓

oil NG→ poor quality → replace ok↓

leak from blade end of compressor NG→ air filter blocked → clean, replace ↓ NG→ dynamic balance of turbine is poor → replace

3. Abnormal Sound turbine end NG→ gas passage became too small → clean, replace

ok↓ compressor end NG→ gas passage became too small → clean, replace ↓ NG→ when countercurrent produced in gas outlet → repair, replace

ok↓ friction between turbine, compressor blade and case NG→ floating bearing worn too much → replace

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4.Vibration

Mainly Check Reasons Remedy friction between turbine, compressor

blade and case NG→ foreign matter entered → replace ↓ NG→ floating bearing worn too much → replace

↓ NG→ dynamic balance of turbine is poor→ check, repair, replace

↓ NG→ dynamic balance of turbine is poor→ replace

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Meaning of the Unit Symbols Used

in This Manual and Its Conversion

item Unit symbols Conversion

power kW 1 kW=1.36 Ps

torque N.m 1 kgf.m=9.81 N.m

speed R/min

Oil/fuel

consumption

G/kW.h 1 g/Ps=1.36 g/kW.h

Swept volume L 1 L=1000 ml

area Cm2 1 m2 =10000 cm2

pressure KPa

MPa

1 kgf/ cm2=98.1

kPa=0.0981 Mpa

force N 1 kgf=9.8 N

length m 1 m=1000m

time Min(s) 1 min=60 s

temperature K(ºC) 273 K=0 (ºC)

voltage V

current A

Crankshaft

angle

ºCA

mass g 1 kg=1000 g

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CYQD32Ti turbo-charge inter-cooling diesel engine Full speed &full load characteristic curve Model CYQD32 diesel engine

Full speed &full load characteristic curve Model CYQD32EGR diesel engine

Full speed &full load characteristic curve Model CYQD32T diesel engine

Full speed &full load characteristic curve Model CYQD32Ti diesel engine

P10 pulley of fan deflection pulley of alternator pulley of crankshaft

p19 correct spray no good no good no good no good no good P14 engine cylinder intercooler compressed air flow exhaust gas outlet

ambient air inlet exhaust gas flow

p16 accelerator handle idle screw gone out device(red wire) start become thicker(black wire)

p22 high speed relay low speed relay charge indicator alternator

preheating lamp key switch preheat relay glow plug vehicle speed sensor temperature sensor overflow valve

p24 HP pump accelerating handle pipe connecting to vacuum pump terminal 1 solenoid valve terminal 2 connecting hose 1 connecting hose 2 idle increasing device

p44 accelerator full open position idle position accelerator full open position idle position average fuel supply average fuel supply average fuel supply