Tài Liệu sửa chữa động cơ D10

Tài liệu sửa chữa động cơ D10, gồm tất cả các hệ thống nhiên liệu, bôi trơn, làm mát... hình ảnh màu trực quan, dùng cho sinh viên nghành cơ khí cơ khí động lực tham khảo hawojc làm đồ án. hướng dẫn trực quan chi tiết từ hãng, các bạn chịu khó dịch ra tiếng việt tham khảo nhé.

Repair Manual of

D10 Engine

CONTENTS

Chapter I The Working Principle of D10 Engine 3

Section I Working Principle of Diesel Engine

3

Section II Working Principle of Common Rail Engine

5

Chapter II The Structure D10 Engine 6

Section I Structure of Common Rail Engine

6

Section II Electronic Control System of Common-rail Engine

9

Section III Main Parts of Fuel System

14

Chapter III Assembling of D10 Euro III Series Diesel Engine 27

Chapter IV Disassembling and Assembling of Fuel System 51

Chapter V Troubleshooting of D10 Engine 89

Section I Failure of Starting

90

Section II Abnormal Sound from Engine

100

Section III Premature Abrasion

110

Section IV Too Low Pressure of Engine Oil

112

Section V Mixture of Oil and Water

117

Section VI Power Deficiency

120

Section VII High Water Temperature in Engine

127

Section VIII Water Return of Engine

131

Section IX Diesel on Oil Pan

133

Section X Black Smokes

134

Section XI White Smokes

137

Section XII Blue Smokes

140

Section XIII Serious Consumption of Engine Oil

142

Appendix I Procedures for Flash Code Diagnosis of Malfunction Lamp 144

Appendix II Flash code List for Malfunctions of High-pressure Common Rail Diesel Engine 145

Appendix III Circuit Diagram of High-pressure Common Rail Fuel Injection System Harness 159

Chapter I The Working Principle of D10 Engine

Section I Working Principle of Diesel Engine

Engine is the power source of automobile, which changes the energy in certain form into the mechanical energy The engine for automobile is a device which converts the thermal energy into the mechanical energy As the combustion is carried out inside the engine (i.e

in the cylinder), the engine is also called internal combustion engine

As for combustion modes, there are two kinds of internal combustion engines, i.e spark ignition engine (gasoline engine) and compression ignition engine (diesel engine) For the spark ignition engine, the gasoline and air are mixed at first, and then spark ignition is carried out at the proper time; for the diesel engine, the diesel oil is injected into combustion chamber in time and then mixed with air, so that the automatic combustion can be carried out with the help of high temperature arising from compression

With high performance on compression and power, the diesel engines are extensively applied to heavy-duty trucks

Fig 1-1 D10 Series Engine

I Terms:

1 Top Dead Center: The position where the piston top is located in cylinder when the

piston is set at the outmost position away from the slewing center of crankshaft, namely

when the piston is set at the highest position

2 Bottom Dead Center: The position where the piston top is located in cylinder when the

piston is set at the nearest position away from the slewing center of crankshaft, namely

when the piston is set at the lowest position

3 Stroke: It means the movement of piston from one dead center to the other dead center for one time

4 Stroke of Piston: It means the distance of piston movement from one dead center to

the other dead center Usually, it is expressed as the letter “S” During one circle of rotation of crankshaft, the piston will reciprocate in the cylinder for 2 strokes

5 Cylinder Capacity: It means the room formed by movement of piston from top dead

center to bottom dead center The capacity of multi-cylinder engine is the capacity sum of all cylinders The engine capacity (also called displacement) indicates the capacity sum of

all engine cylinders

6 Capacity of Combustion Chamber: The room above piston top when the piston is

located at top dead center is called combustion chamber The capacity of this room is called capacity of combustion chamber

7 Total Capacity of Cylinder: It means the room of all cylinders above piston top

(namely the capacity sum of cylinder and combustion chamber) when the piston is located

at bottom dead center

8 Compression Ratio: It means the ratio of capacity sum of cylinders to capacity of

combustion chamber It indicates the degree of gas compression in cylinder when the piston is moving from bottom dead center to top dead center At present, the prevalent compression ratio of diesel engine is 16~21

II Working Cycle of Engine

The working course of engine is composed of 4 continuous

processes, namely intake stroke, compression stroke, expansion

stroke and exhaust stroke, and such a complete working course

is called as a working cycle To make the engine run constantly,

the working cycle must be carried out repeatedly During a

working cycle, if the crankshaft rotates for two circles and the

piston reciprocates for two times to cover four strokes, such an

engine is called four-stroke engine While during one working

cycle, if the crankshaft rotates for one circle and the piston

reciprocates for one time to two strokes, such an engine is called

two-stroke engine The working cycle of four-stroke engine is

shown as follows:

1 Intake Stroke: During it, the piston moves from top dead center to bottom dead center,

the capacity above the piston is increased, the pressure in cylinder becomes lower than the atmospheric pressure and the pressed air is compressed into cylinder promptly At the same time, the intake valve is opened and the exhaust valve is closed When the piston arrives at the bottom dead center, the intake valve is closed and the air intake terminates

2 Compression Stroke: When the piston arrives at the bottom dead center, the

crankshaft will continue rotating under the effect of inertia force of flywheel and the piston can move upwards from bottom dead center At the same time, the intake and exhaust valves are closed and the air in cylinder is compressed into the combustion chamber When the piston arrives at the top dead center, the compression stroke completes The air pressure in cylinder will be about 2,800~2,600kpa

3 Expansion Stroke: When the “compression stoke” finishes, the diesel oil is injected into the cylinder by the injector, the compressed combustible air mixture burns immediately, and the temperature as well as the pressure in cylinder increases sharply The piston is driven by the gas pressure to move downwards and make the crankshaft rotate to carry out expansion through connecting rod As the piston moves downwards, the pressure and temperature of gas decrease When the piston arrives at the bottom dead center, the expansion stroke terminates

4 Exhaust Stroke: During this course, the piston moves upwards from bottom dead

center, the exhaust valve is opened, and the waste gas is exhausted from cylinder under the effect of residual pressure of itself and upward movement of piston When the piston arrives at the top dead center, the exhaust valve is closed and the exhaust stroke terminates

III Expansion Sequence

When the crankshaft rotates for two circles, each cylinder will execute expansion for one time As D10 series diesel engine for heavy-duty truck has six cylinders To secure the stable operation of engine, the crankshaft has been specially designed and enables each cylinder to execute expansion at different times The expansion sequence of six-cylinder

Fig 1-2 Schematic Diagram of Working Principle of Engine

four-stoke engine is 1-5-3-6-2-4

Section II Working Principle of Common Rail Engine

I Definition of Common Rail Technology

The common rail technology refers to a fuel supply means, in which the generation course

of injection pressure and injection course are completely separated in the closed-loop system consisting of the fuel supply pump, common rail component, and injector

II Features of Common Rail Electronically-controlled Fuel Injection Technology

It can not only help reach a relatively high injection pressure and achieve the control over the injection pressure and fuel injection quantity but also enable the pilot injection and sectional injection, which accordingly optimizes the fuel injection features, lowers the diesel engine noise and greatly reduces the discharge of the harmful ingredients in the exhaust gas Its features are as follows:

1 Designed with advanced electronic control devices and high speed electromagnetic switch valves, facilitating the control over the fuel injection course and providing many controllable parameters, which benefit the whole course optimization of the combustion of the diesel engine

2 The common rail fuel supply method is applied, which brings small pressure fluctuation

of the fuel injection system, little interference between various injectors, relatively high control precision in the injection pressure and precise control over the fuel injection quantity

3 The high speed electromagnetic switch valve with a high frequency can be controlled flexibly, which enables a wide adjustable range of the injection pressure of the fuel injection system and can also achieve the functions such as pilot injection more simply to offer effective means to the optimization of the fuel injection law of the diesel engine, improvement on the performance and reduction of the exhaust gas discharge

4 The system structure can be transferred easily and is adaptable in a wide range, especially it is able to well match with all the light, medium and heavy-duty diesel engines nowadays, which shows a good prospect on the market

Chapter II The Structure D10 Engine

Section I Structure of Common Rail Engine

The D10 Series diesel engine for heavy-duty truck can sufficiently meet the power requirements of 91 Series truck of corresponding tonnage as well as the requirements of other purposes such as engineering machinery It is also featured by compact structure, fine rigidity, reliable operation, long service life, good performance and well economical efficiency

The structure features of diesel engine are summarized as follows:

a One cylinder head matches with one cylinder, which is good for reliable operation and convenient removal

b The oil injection pump is set at the left side (seen from the free end of engine), which is good for arrangement on vehicle

c The built-in oil cooler is applied, working safely and reliably

d All engines of this series are six-cylinder in-line engines, which are highly interchangeable and convenient for complete vehicle assembly

The engine for automobile is mainly composed of crank connecting rod mechanism, distribution mechanism, fuel supply system, lubrication system, intake/exhaust system and starting system

I Overview of Common Rail Engine

In terms of the D10 engine of Euro III manufactured by China National Heavy Duty Truck Group Co., Ltd., with application of the most advanced design means and testing methods

in the world and supported by the huge database of RICARDO and experienced designers, and with the help of the software such as three-dimensional finite element, WAVE combustion analysis and CFD hydrodynamic calculation analysis and components and parts testing equipment, the interior structures of important components and parts are originally designed, the interior structures of the engine body and cylinder head are improved qualitatively; on the basis of the WAVE combustion simulation, hydrodynamic calculation and optimal supercharger match, the combustion chamber, atomization and airflow are reasonably organized, the water flow and thermal load of the cylinder and cylinder head are improved fundamentally, and the thermal load and mechanical load are improved and its shockproof performance is greatly enhanced The key components and parts such as connecting rod, crankshaft, piston, piston ring, and bearing shell are optimized in material selection and key structural size, and the thermal and mechanical shock resistances are enhanced greatly, which underpins the reliability improving, noise reducing and power promoting The engine has a B10 service life not less than 12,000 hours, with a complete machine noise lower than 97 dB

The application of generation 2 electronically-controlled common rail fuel injection system and four-valve structure and its excellent combustion and air-inflation performance bring the engine a very high dynamic behavior With a constant engine displacement, the maximum power of the engine can reach up to 294 kW, namely, 400 hp The engine can satisfy the discharge requirement of Euro IV if the common rail pressure is slightly adjusted and necessary processing system is provided additionally while the installation dimensions of the complete machine keep unchanged, which greatly facilitates the matching of the main engine plants

The structural features are summarized as follows:

New generation of electronically-controlled common rail fuel injection system of Denso

Noise being lowered to less than 97 dB (A)

Lowering the combustion noise: One of the reasons for selecting the common rail fuel injection system is that the common rail system can do better in controlling the engine noise; and the pilot injection is a very good means The pilot injection fuel being injected into the cylinder beforehand has adequate combustion readiness time, and the pilot injection fuel has a very small quantity, which brings little premixed fuel gas in the preliminary combustion This greatly improves the generally inevitable and inherent situation that the diesel engine has not only high preliminary combustion value and great combustion noise As a result, the pilot injection of the common rail fuel injection system can obviously lower the combustion noise In addition, the electronically-controlled common rail system can precisely compensate the unbalance between the fuel injections

of various cylinders, which cannot be achieved by the mechanical pump and greatly improve the shock situation of the engine as a result

Enhancing shock absorbing behavior and reducing noise: The improved design of the cylinder body and crankcase fully strengthens its rigidity; and through the three-dimensional finite-element vibratory response analysis and actual testing, it effectively reduces the vibration and noise of the cylinder body assembly, and noise radiation The noise reduction measures are fully weighed in designing the parts like rocker arm bonnet

Shock absorbing measures: The crankshaft vibration damper is redesigned through analyzing the former torsional vibration system of the crankshaft

JOCOBS Electronically-Controlled Brake System

The engine is provided with the exhaust type brake device of Jacobs (U.S.A), working with the exhaust brake at the same time; when the engine speed reaches 2200r/min, a braking power not less than 146 kW can be obtained which obviously enhances the brake power

of the vehicle and improves the vehicle security

New generation of cold starting apparatuses

The electronic control system can automatically indicate whether the engine is in a starting state, and automatically adjust the advance angle and fuel injection quantity in accordance with the air and water temperature, and therefore, the cold starting performance of the engine is obviously promoted

The resistance air preheater can, under the control of the electronic control system, perform the heating in advance before the engine starts, and automatically continues to heat for some time in accordance with the engine speed after the engine runs, which not only greatly enhance the cold starting performance of the engine but also obviously reduce the phenomenon (inevitable for traditional diesel engines) in which the unburned diesel gives out white smoke in case of low temperature start

Excellent driving and controlling performance

The electronic control system can automatically adjust the fuel injection of the injection nozzle according to the different working conditions such as engine starting, idle speed, departure, acceleration, steady speed, neutral position, astern running, air conditioner using, and power take off, and thus the driving and controlling performance is greatly enhanced

The electronic control system can, in accordance with the difference in the rotation speeds

of various cylinders in operation, automatically balance the fuel injection quantities of various cylinders to make the rotation speeds of various cylinders in operation become exactly the same so as to enable the engine to achieve a very steady idle speed

CEVB Technology

As an auxiliary braking apparatus, the EVB system is an engine retarder and based on the traditional exhaust auxiliary braking apparatus of the butterfly valve, and it can further enhance the braking efficiency of the engine

Fig 2-1 Outside View of Common Rail Engine

II Fundamental Structure of Common Rail Engine

1 Engine Body

Based on the wide type cylinder body of the original design of Steyr in compliance with Euro II Emission Standard, the engine is greatly altered in order to further lower the engine noise, and significantly improved to promote the thermal load of the engine However, the improvement is mainly embodied by the alteration to the casting blank, and what is related

to the machine tooling is altered little; and therefore, the cost of the cylinder body is equivalent to that of the cylinder body in compliance with Euro II Emission Standard

Fig 2-2 Engine body, crankcase, and flywheel casing Main parts: 1 Engine body 2 Crankcase 3 Flywheel casing 4 Cylinder casing 5 Cylinder head stud 6 Rear oil seal 7 Fuel injection pump bracket 8 Thrust plate 9 Hexagon bolt 10 Main bearing stud

The dry type cylinder casing is applied to the engine body, and it is transition fit between the cylinder casing and the cylinder holes of the engine body The thin-wall cylinder casing

is manufactured by abrasion-proof alloy cast iron, with a wall thickness of 2 mm; and the testing of the cylinder casing demands the dedicated measuring unit The internal surface

of the cylinder casing is covered by specially-made overlapping curves, and this brings good effect on the acceleration of running-in and abrasion-proof performance

The front end of the engine body is connected to the timing gear chamber while its rear

end is connected to the flywheel casing

There is a conjunction surface for mounting the fuel injection pump bracket in the middle

of the left side of the engine body; after the said bracket is mounted, the components will

be processed, and the fuel supply pump bracket shall not be disassembled after the components are processed so as not to make the installation precision of the fuel supply pump be affected by the disassembly and reinstallation

2 Crank-connecting Rod Mechanism

Crankshaft:

The crankshaft of the D10 series diesel engine is manufactured by steel die forging, with 42CrMo steel as its material The crankshaft has 12 balancing weights, a main journal of Ф100 mm and rod journal of Ф82 mm, and the width of each journal is 46 mm; and the crankshaft goes through the treatment of tufftride and has a good fatigue strength and abrasive resistance

Crankshaft Vibration Damper:

The silicon oil damper (outside diameter, Φ280 mm) is adopted, with good reliability and effect, and torsional-vibration amplitude is controlled within 0.2°

Flywheel:

The SAE1 flywheel is adopted, the gear ring has 136 teeth, and the matched clutch wearing-piece has a diameter of Φ430 mm Be noticed that it is clearance fit between the SAE1 flywheel and gear ring (16-hole flywheel)

Piston:

The forced cooling type of built-in oil-cooled gallery piston is applied, the piston is manufactured by MAHLE 142 with a higher thermal load resistance, and the small end of connecting rod is of wedge structure, which enhances the piston strength accordingly The first ring groove is inset by cast iron, which is required to have a good sticking to the piston only so as to guarantee a good adhesive strength and heat transfer effect The piston has two gas rings and one oil scraping ring; the first gas ring is the double ended trapezoidal tubbish ring in the cast-iron inset ring groove, and the working surface is plated with chromium-based ceramic, which benefits the running-in, anti-galling and antifriction effect The second gas ring is a surface-phosphatized complex-alloy tapered-face ring, with a ring height of 3 mm, and the assembling clearance between the ring and ring groove is 0.08~0.115 mm The third ring is a coil-spring-loaded alloy cast iron oil ring, with a ring height of 4 mm, and the double-edged surface is plated with chromium, with a strong oil scraping capability, and the clearance between the oil ring and ring groove is 0.04~0.075

mm The piston pin hole has a diameter of Ф50 mm and the complex molded lines are applied to the piston skirt to guarantee that the piston and the cylinder casing are well contacted with each other, and there is a 0.02 mm-thick spray coating of graphite for the skirt surface, which brings a good antifriction effect

The compression height of piston is 80 mm, and the top land has a shallow ω-type combustion chamber The compression clearance after the piston is mounted in the cylinder is 1 mm The piston is cooled by engine oil via injection nozzle

Piston Pin:

The round structure with a diameter of Ф50 mm is applied, and its internal and external surfaces both go through the treatment of carburizing and quenching, with a case hardness of 57~65HRC

positioning structure of 60° and two connecting-rod bolts of M14×1.5 for the connection, and the screwing up of the connecting-rod bolts shall be in conformity to the requirements

of Rotation Angle Screwing Method

The connecting-rod bolt has a performance grade of 12.9, 42CrAH being applied The rotation angle anti-loosening measures are applied to the connecting-rod bolts, and in accordance with the requirements, the connecting-rod bolts are not allowed to be reused

or used beyond the limit so as to avoid fracture and collapse accidents of the machine The small end of the connecting rod is manufactured by steel-backed copper-aluminum alloy, with a thickness of 2.5 mm; and its lubrication groove is T-shaped, with a big pressure bearing surface

The weight difference between the connecting rods in the same group in the installation is not more than 29g

Connecting Rod Bearing Shell:

The steel-backed unequal-thickness bearing shell with a new plating material (supplied by Miba) is applied to the connecting rod bearing shell; the upper and lower bearing shells use different material, the upper bearing shell is able to sustain a higher detonation pressure, and the two shells shall not be misplaced in the assembly

Main Bearing Shell:

The steel-backed equal-thickness bearing shell with a new plating material (supplied by Miba) is applied to the main bearing shell and can sustain a higher detonation pressure The seven main bearing shells share the same width, and are all universal and manufactured by the steel-backed tin-aluminum alloy, with a hardness of HV35~45

Fig 2-3 Main Moving Parts

1 Crankshaft 2 Crankshaft gear 3 Flat key 4, 5 Cylindrical pin 6 Flange 7 Shock absorber 8 Belt pulley 9 Hexagon bolt 10 Main bearing shell 11 Thrust plate 12 Connecting bar 13 Connecting-rod bolt 14 Connecting rod bearing shell 15 Piston 16 Piston ring 17 Retaining ring 18 Piston pin 19 Retaining ring 20 Bush 21 Flywheel 22 Flywheel ring gear

3 Valve Mechanism and Cylinder Head

Cylinder Head:

The special cylinder head for Euro III emission standard is applied, which is made from NiCr pearlitic alloy cast iron Each cylinder is provided with one cylinder head, and a double-valve intake & exhaust and CEVB system is applied

In order to prevent engine oil from coming into air passage through the gap of valve guide, a sealing device is installed above the valve guide

Each cylinder has four M16 king bolts and two M12 studs shared with adjacent cylinders The auxiliary nuts of studs are held down through the clamping blocks with V-shaped pressure surface The main bolts and auxiliary nuts are fastened by torque-angle tightening method

of Ф40.6mm, and the valve stem is chrome plated at its surface

Fig 2-4 Cylinder and Valve System

1 Cylinder head 2 Fuel injector bush 3 Valve guide 4 Valve locking clamp 5 Valve spring 6 Upper seat

of valve spring 7, 8 Valve bridges 9, 10 Rocker arms of intake and exhaust valves 11, 12 Intake and exhaust valves 13 Valve tappet 14 Valve push rod 15 Lower part of rocker arm bonnet 16 Seal ring of upper part of rocker arm bonnet 17 Upper part of rocker arm bonnet 18 Valve rocker arm seat 19 Cup ring 20 Camshaft 21 Hexagon socket head screw 22, 23 Valve clearance adjusting screw and nut

4 Overview of Fuel Supply System

The main components of the system are shown as follows, taking HPO fuel pump as an example

Fig 2-5 Common Rail Fuel Injection System The Generation II electronic control common rail fuel injection system from DENSO Corporation

is applied, the maximum common rail pressure of which can reach 180 MPa It can achieve 5 times of fuel injection within one second, and can adjust fuel injection quantity, times, common rail pressure and advance angle flexibly and accurately based on rotation speed, fuel temperature, load, water temperature, boost pressure, and the running status of engine and vehicle, so as to achieve the best emission performance, noise level, power performance, economy, stability and low-temperature starting performance of the engine, and the optimal maneuverability of the vehicle Now, D10 model is calibrated according to Euro III emission requirements, so only 140 MPa of the common rail pressure and two times of fuel injection (main injection and pre-injection) are used In this system, the fuel atomization is enough to meet the regulatory requirements on particulates, while the accurate electronic control of advance angle plus pre-injection can well meet the regulatory requirements on NOx If the full common rail pressure (180 MPa) as well as the pilot injection, post injection and later injection all are applied, with adjustment and calbrication plus the post-exhaust treatment system, such a system is fully capable of meeting Euro IV emission requirements that is to be implemented And also, the system presents nice idle performance, for its electronic control system can automatically balance the fuel injection quantity

of each cylinder depending on the difference of rotation speed for each cylinder in working so as

to make the rotation speed of all cylinders in working same with each other and thus achieve the stable idle performance of engine

The system mainly consists of fuel pump, common rail components, fuel injector assembly, ECU control assembly and various sensors for different purposes

1 HP0 fuel pump is applied The lubricating oil required by the fuel pump comes from an oblique oil hole at the left side of cylinder block, and the lubricating oil returns back to the crankcase viz the lubricating oil pipeline

2 In consideration of the reliability and service life of high-pressure common rail fuel injection system, a primary filter is installed between the fuel tank and the fuel pump, which is not provided along with the ex-factory engine while is provided by the complete vehicle assemblage plant

3 The 670* fuel injector assembly is applied in this system There are two kinds of QR code identification on the fuel injector assembly, of which, one is machine-reading code and the other is the one with 30 characters for manual reading

For replacement of fuel injector assembly, the compensation valve QR of the new one should be written into the ECU control assembly by personnel of an authorized service station

(1) Fuel circuit system

The fuel pump is a “triple-cam” high-pressure plunger pump As for the “triple-cam”, it refers to the cam provided with three bumps for driving the fuel pumping plunger (generally, only one bump is set on the cam) Thus, for each rotation circle of cam, three fuel pumping actions can be achieved

to enhance the fuel injection quantity by three times In particular, during the start of diesel engine, the increasing rate of oil pressure inside the common rail can be accelerated to facilitate the start

of diesel engine The oil return valve is equipped on the high-pressure fuel pump and the oil return process would be started when the pressure inside the pump body exceeds 225kPa Fuel filter is equipped with a limiting valve and the oil return process would be started when the fuel pressure exceeds 319kPa High-pressure fuel pump is composed of two plunger pumps and each pump has a fuel-supply pressure regulating valve controlled by the ECU

(2) Common rail system

Common rail is connected with the high-pressure oil pipe of each cylinder through the flow buffer which is used to reduce the pressure fluctuation in the common rail and high-pressure oil pipe and automatically cut off the oil supply to the injector when the oil flow is excessive (leakage) The spring-type common-rail pressure controller installed at one end of the common rail would automatically open to reduce the pressure when the common rail pressure achieves 140Mpa and automatically close when the common rail pressure drops to 30Mpa The fuel pressure sensor installed on the common rail is pressure-sensitive resistance type and provides the feedback signal of actual fuel pressure inside the common rail to the ECU

(3) Fuel injector system

The high-pressure fuel in the common rail directly flows into the fuel return passage by which the needle valve and electromagnetic valve at the lower part of injector control the control room at the top of hydraulic piston which is equivalent to a ram When the electromagnetic valve is cut off, the combustion pressures inside the control room and the fuel chamber of needle body are equivalent The fuel pressure of upper part of hydraulic piston and the return spring force would get the needle valve of injector closed, so that the injector does not spray When the electromagnetic valve is turned on, the fuel return passage of control room is open and the fuel pressure on the upper part of hydraulic piston declines rapidly, so that high-pressure fuel inside the fuel chamber

of needle valve of injector to make the injector spray the fuel

5 Lubrication System

(1) Oil pan:

The punched large-capacity oil pan has a deep flanging with the joint surface of crankshaft with a large stiffness The lower joint surface is pressed by 12 supporting blocks of oil pan and bolts M8, coupled with concave oil pan flexible gasket, so the sealing performance is good, there is no oil penetration and the noise of diesel engine is dramatically decreased The whole series of oil pans are basically identical

(2) Engine oil cooler:

Plate-type oil cooler can improve oil cooling effect obviously The structure of oil cooler has been inspected with vibration test and can fully guarantee the safety and reliability In order to prevent the damage of engine due to the oil lack caused by the cooler blockage or the low oil temperature and large viscosity during the cold-start process as well as the higher resistance of oil cooler, the safety valve (bypass valve) of which opening pressure is 600 ± 50kPa is set in the oil circuit of engine

(3) Main oil passage pressure limiting valve:

The main oil passage pressure limiting valve is located at the right lower position of crankcase and protrudes in the inner chamber of oil pan It adjusts the gasket to ensure the opening pressure of

500 ± 50kPa The valve has been corrected before the assembly, so the user can not change it randomly

(4) Engine oil filter:

The large-capacity oil filter can adapt to the more smoke of Euro III engine

(5) Engine oil pump:

Oil pump is some kind of gear pump, and the number of teeth is 10 The thickness of single-stage pump is 45mm In addition to the dual-stage structure of road all-wheel drive vehicle, other vehicle models are equipped with single-stage pump

Fig 2-6 Lubrication System

6 Cooling System

(1) Water pump:

The water pump of D10 series of diesel engine is installed at the front of engine with the volute casing cast as a whole above the timing gear chamber The water out of volute casing directly flows into the water chamber at the right side of body, and the coolant crosses over the oil cooler and flows into the water interlayer of cylinder barrel through the passage hole at the right bottom

to cool the cylinder barrel and then flows into the water chamber of cylinder head through the upper water hole to cool the cylinder head, and finally is discharged from the water outlet of cylinder head into the water outlet pipe of which end is equipped with a thermostat The thermostat has two outlets, of which one leads to the water tank and the other leads to the inlet of water pump (that is, the small cycle) When the coolant temperature is at 80±2℃, the thermostat starts to open and fully open when the temperature reaches 95℃, and at this point, all of the coolant is pumped into the body after being cooled by the radiator, but when the coolant temperature is below 80±2℃, the thermostat would cut off above channel, so the coolant would directly flow into the inlet of water pump to make the diesel engine warm up as soon as possible

Oblique oil passage

Valve mechanism

Cooling oil nozzle of piston

Crankshaft main bearing oil passage Auxiliary oil

Main bearing Oblique oil

Oil pressure sensor

Pressure limiting valve of main oil passage Pressure limiting valve of engine oil pump

Engine oil cooler

Engine oil filter

Engine oil pump

Oil pan Bypass valve

and meet the required thermal conditions, so as to avoid the low-temperature wear and extend diesel engine life 120cm3 of Shell Roller Bearing Grease A shall be added into the oil chamber of water pump and there is a need to add the grease regularly

(2) Expansion Tank:

This part is assembled by the whole-vehicle factory, and the diesel engine is not equipped with this part when it leaves the factory Its role is to eliminate the steam from the low-pressure part of cooling system so as to prevent the air resistance phenomenon and add the coolant Pressure inside the expansion tank shall be maintained at 50kPa and the location of expansion tank must

be 400mm higher than the diesel engine and radiator

A variety of tank cap of cooling system shall be kept intact and closed The cooling system to maintain the internal pressure 50kPa will increase the cooling efficiency and prevent the boiling phenomenon

(3) Fan:

The circular plastic fan with 10 blades of which diameter is not less than Ф640mm is adopted The driving method of fan is divided into rigid drive and viscous drive (i.e., driven by silicon oil clutch)

Viscous fan is controlled by a bimetal temperature sensing element according to the temperature,

so the energy-saving effect is obvious, and the more important is to ensure the good thermal state

of diesel engine, which is helpful to improve the engine operation and prolong the service life The main principle of such fan is that the driving wheel inside the clutch shell is driven by the diesel engine, and the fan blades and the shell are connected together as a whole, and there is a certain gap between the driving wheel and the shell, and when the gap is filled with the silicone oil of tremendous viscosity, the driving wheel drives the shell to rotate, but when the gap is free of silicone oil, the driving wheel would idle (in fact, it is capable of driving the fan to rotate at 25% of nB) Bi-metal tactile rod is the valve which regulates the silicone oil to enter the work space, so that the operation of fan is controlled under the temperature When the front wind temperature of fan is below 40℃, bi-metal tactile rod closes the valve of silicone oil silo, and at this time the driving wheel basically does not pass the power and the driving wheel rotates at the 25% of nB, and when the temperature is greater than 60℃, the valve of silicone oil silo is fully open and the work space is filled with silicone oil, and at this time the rotation speed of fan is 95% of the speed

of driving wheel

Attention shall be paid when using the viscous fan to that it is unallowable to lay down the fan levelly after being removed, otherwise the silicone oil would leak from the mating clearance of sensor shaft to lead to the failure of fan

Fig 2-7 Cooling water circulation of cooling system

1 Water valve 2 Heating radiator 3 Exhaust pipeline of radiator 4 Cooling water discharge pipeline of engine 5 Water inlet pipe of heating radiator6 Water outlet pipe of heating radiator 7 Limiting valve of expansion tank 8 Expansion tank 9 Thermostat 10 Water pump 11 Oil cooler

7 Turbocharging and Intercooling System

1) Turbocharger:

The D10 National III two-valve (common-rail) series engine uses a radial-flow exhaust-gas turbocharger, which is provided with air bleed valve This turbocharger can effectively improve the vehicle performance under low or medium running speed and reduce the exhaust gas emission The engine oil used for lubricating and cooling turbocharger is guided out from main oil passage

of engine and directly returns to the lower part of crankcase

The turbocharger works at a very high rotation speed that may reach 105,000r/min So, after the diesel engine starts up, loads shall not be added to the diesel engine unless an adequate time (approximately 5 minutes, or slightly less in case of short shutdown) is given for the engine to idly run When the diesel engine runs at the high speed and under the heavy loads, it shall not be immediately shut down Instead, you shall gradually reduce the load and rotation speed of engine, and make the engine idly run for 3~5 minutes Or else, the turbocharger bearing will be damaged and disabled For a disassembled turbocharger, you shall add clean engine oil into its oil inlet when reassembling it

Fig 2-8 Intake and Exhaust System of D10 Turbocharger

Table 2-1 List of Special Parts for A7 Series Engine

Section II Electronic Control System of Common-rail Engine

Engine ECU checks the status of the engine according to the signals from the sensors constantly and then calculates the amount of fuel injection according to the engine state etc to start the actuator as well as keep the engine at the top condition Injectors can be started by the charging circuit inside the electronic drive unit (EDU) or the engine ECU The actuator circuit is different due to the specifications of different models ECU also has a diagnostic function which can be used to record the system failure

I Sensor

The sensors installed at the engine include: (provided by engine factory)

(1) Ne Sensor (rotation speed sensor): (installed on the flywheel shell)

Crankshaft position sensor is installed near to the crankshaft timing gear or flywheel The sensor unit is electromagnetic induction (MPU) type When the engine speed pulse gear which is installed

on the crankshaft goes through the sensor part, the magnetic field of the coil inside the sensor changes, which produces the AC voltage Engine ECU would detect the AC voltage as the signal The pulse times of engine speed pulse unit depends on the specification of the vehicle installed with the sensor

Direct measurement on the sensor (40:41): 125 ± 17Ω (20℃)

(2) G Sensor (Cylinder detection sensor); (installed on the fuel pump)

The cylinder detection sensor of HP0 systems is installed on the fuel pump unit The sensor unit is magnetoresistive element (MRE) type For the MRE sensor, when the pulse-generating device gets through the sensor, the magnetic resistance changes and the voltage going through the sensor also changes The variation of enlarged voltage of the internal IC circuit is output to the

engine ECU The pulse times of TDC pulse-generating device depends on the specification of the vehicle installed with the sensor

(3) Coolant Temp Sensor: (installed on the water-out pipe)

Coolant temp sensor is installed on the cylinder body to detect the coolant temperature The sensor is thermistor type

(4) Intake Temp.Sensor; (installed on the air intake pipe)

Intake temp sensor detects the temperature of air which has gone through the turbocharger The sensor part for detecting the temperature contains a thermistor The thermistor is used to detect the intake air temperature, and its resistance value varies with temperature

(5) Fuel Temp.Sensor; (installed on the oil-return connecting seat)

This is a thermistor type sensor and can detect the fuel temperature In the HP0 system, the sensor is installed in the overflow pipe of injector

℃ -30 -10 0 30 50 80 100

(6) Intake Press Sensor; (installed on the intake pipe)

The sensor is the semiconductor type It uses the piezoelectric effect that the change of the pressure of silicon element inside the sensor would lead to the change of the resistance When the engine is idling, the intake pressure is same as the atmospheric pressure In case of the large power, intake pressure can reach more than 220Mpa

(7) Rail Press Sensor; (installed at the left side of common rail)

See the section of oil pump of fuel system for details

(8) Oil Press Sensor (electronic oil pressure sensor is optional)

(9) Diesel moisture alarm sensor (installed on the diesel prefilter) (optional)

The sensors installed on the vehicle include: (provided by whole-vehicle factory)

(1) Accel Pedal Sensors No.1 and 2

Accel pedal sensor converts the opening of accelerating pedal into the electronic signals, and output it to the engine ECU Such sensor is a non-contact type sensor Connecting rod and accelerator pedal are driving together, and the output terminal voltage would change according to the rotation angle of connecting rod In addition, since there are two sensor output systems, it will produce a compensation output voltage

Accelerating

Pedal

APP1 (21:135)

APP2

(2) Vehicle Speed Sensor; (installed at the output terminal of gearbox)

If the whole-vehicle factory decided to use the cruise and speed-limiting etc functions, the signal

of speed sensor shall be input into the ECU (ECU27 pin)

The methods for inputting the speed sensor signal into the ECU include the following:

One is that a circuit of signal is directly connected to pin No.27 from the speed sensor, while the K value of odometer of each vehicle model shall be provided to the engine factory (Pulse / km), K = 8,000 × I / (2ΠR × Y), of which: R: tyre radius; I: rear axle ratio; Y: 1st reduction ratio of gearbox (e.g 1.545)

The other is that a circuit of signal is connected to pin No.27 from the output terminal of speed meter (C3 signal), and its K value is fixed, usually 4,000 /km

(3) PTO Accel Sensor; (installed on the superstructure of engineering vehicle)

Actually, PTO refers to a kind of power take-off when the engine is idling and is composed of power take-off switch (PTO-SW) and PTO potentiometers (AD10) During the operation, the engine shall be at the idle state, that is, the engine shall be in the neutral gear and the clutch shall

be released It is first necessary to close the PTO switch to get the ECU into PTO mode, and then turn the PTO potentiometer, so ECU receives the varied voltage of potentiometer to increase the idle speed of engine according to the calibrated MAP

(4) Idle Speed Control Volume Sensor

The idle speed of engine can be manually regulated by manipulating control potentiometer of idle speed volume (it is usually able to raise up 150rpm or so) Try not to adjust

Idle speed is based on the water temperature: when the water temperature is -30℃, idle speed is 850rpm; water temperature is -20℃, the idle speed is 800rpm; water temperature is -10℃, idle speed is 750rpm; water temperature is 0℃, idle speed is 700rpm; water temperature is 40℃ above, idle speed is 650rpm

(5) Exhaust brake relay;

(6) Bleeder relay1, bleeder relay2 (optional);

(7) Brake Relay (for acquiring the signal of brake indicator lamp)

IV Actuator

PCV×2 2 pressure control electromagnetic valves of oil supply pump; (installed on the top of fuel pump)

See the injection pump for details

Injector×6 6 electromagnetic valves of injector; (installed at the rear of injector)

See the injector for details

6 electromagnetic valves of bleeder brake device (optional for engine), DC24V, 0.78A/piece

V Indicator Lamp

(1) Exhaust Brake Lamp;

(2) Check Engine Lamp;

(3) Heater Lamp

VI Communications Data Connection

(1) CAN1 port is used for accessing the diagnostic tools and SOB data read-in;

(2) CAN2 port is used for the connection between the ECU sensor information and whole-vehicle instrument;

(3) (SINK) TAC2 is the signal output of ECU rotation speed sensor

Section III Main Parts of Fuel System

The main parts of fuel system are fuel pump, common rail components, fuel injector assembly, ECU control assembly and various sensors

I Fuel Pump

Generally, the HP0 fuel pump is composed of the pressure transfer system in traditional in-line (two-cylinder) pump, the PVC (pump control valve) controlling fuel displacement, the crankshaft position sensor (G sensor) and the fuel inlet pump

The functions of parts of fuel supply pump are listed in the following table:

Overflow valve

It sucks the fuel from the fuel tank, and then supplies this fuel to the pumping mechanism

Pump control valve (PCV) It regulates the fuel pressure in fuel pump

Pumping mechanism

Tappet It transfers the reciprocating motion to the tappet

Plunger It reciprocates to pump and compress the fuel

PCV (Pump Control Valve)

Fuel Outlet Valve

Crankshaft position sensor (G

1 Fuel Inlet Pump

The oil inlet pump (integrated in the fuel pump) sucks the fuel from the fuel tank, and then supplies this fuel to the pump chamber via the fuel filter There are two kinds of fuel inlet pumps, i.e trochoid pump and impeller pump The functions of trochoid fuel inlet pump are specified below The camshaft drives the internal/external rotor of fuel inlet pump to rotate According to the space produced by motion of internal/external rotor, the fuel inlet pump inhales the fuel to the suction port, and then pumps this fuel to the drain port

2 Pump Control Valve (PCV)

The PCV regulates the pressure of fuel rail by adjusting the fuel discharge volume of fuel pump The fuel volume discharged to fuel rail by fuel pump is subject to the timing of electricity imposed

on PCV

The fuel is inhaled to the fuel inlet pump from the fuel tank, and then transferred to the pumping mechanism via the pump control valve (PCV) To regulate the pressure of fuel rail, the PCV adjust the fuel volume sucked by pumping mechanism to the necessary discharge volume, and then pumps the fuel to the fuel rail via the fuel outlet valve

The working principle of PCV is shown in the following figure:

The action of PVC during each stroke is listed in the following table

Stroke (C)

Electric power is provided to turn off the PCV and close the fuel return passage when the timing is suitable for the discharge volume At this time, the pressure in plunger chamber rises Therefore, the fuel flows through the fuel outlet valve (reverse cutoff valve), and then is pumped to the fuel rail In details, after the PCV is turned off, the elevation volume of plunger becomes the discharge volume, which can be controlled by changing the closing timing of PVC so as to govern the pressure of oil rail

Stroke (A’)

When the camshaft exceeds the maximum elevation, the plunger will come into the falling stroke, and the pressure in plunger chamber will reduce At this time, the fuel outlet valve is closed, and fuel pumping

is stopped Furthermore, the PCV will be de-energized and opened, and the low-pressure fuel will be inhaled to the air chamber In details, the system will comes into the Mode A

The execution circuit is shown in the following figure The ignition switch turns on or off the PCV relay to apply the electricity onto the PCV According to the signals transmitted by each sensor, the ECU controls the opening/closing timing of PCV, determines and ensures the target fuel supply volume to provide the optimal fuel rail pressure

Working Principle of Pump

From Fuel Tank

At the Time of Increased Discharge Volume

At the Time of Decreased Discharge Volume

Necessary Discharge Volume for Pumping

To Fuel Rail

3 Pumping Mechanism

The camshaft is driven by the engine, and the cam pumps the fuel supplied by fuel inlet pump through the driving effect of tappet on plunger The discharge volume is controlled by the PCV The fuel is pumped to the cylinder from the fuel inlet pump, and then transferred to the fuel outlet valve

4 Crankshaft Position Sensor

When the pulse producer device passes the crankshaft position sensor (TDC (G) Sensor), the magnetic resistance will vary, and the voltage passing this sensor will also change The change of voltage will be amplified by the internal IC circuit and then output to the engine ECU There is a disk gear at the centre of camshaft for fuel pump On this gear, a notch is made for each 60°, and

an additional notch is provided Thus, once the engine (with six cylinders) rotates for two circles, this gear will output seven pulses With the engine rotation speed pulse and TDC pulse combined beside the engine, the pulse behind the additional notch pulse can be identified as 1# cylinder

PCV (Pump Control Valve)

Plunger

Fuel Inlet Pump Pulse of G Sensor

Camshaft

To Fuel Rail Fuel Outlet Valve

5 Air Bleeding of Fuel Circuit

Screw off the 10mm bolt, pump the manual fuel pump, and screw down the bolt when there is no

air at the bolt You must remember that it is forbidden to bleed the air by screwing off the bolt for

fuel return valve (since it is very easy for the steel ball and spring in such a valve to fall off.)

Note: After replacing the MANN HUMEL fuel filter, you must open the fuel inlet pipe of fuel pump

to bleed the air, and then screw off the 10mm bolt to bleed the air Alternatively, you may fill the

prefilter with diesel oil and then conduct installation Or else, it is very difficult to completely bleed

the air from the low-pressure fuel circuit, and this will disable the engine from starting up

Sensor (G Sensor)

G Pulse

Ne Pulse

Standard Engine Rotation Speed Pulse of 1# Cylinder Standard Engine Rotation Speed Pulse of 6# Cylinder

Standard G Pulse of 6# Cylinder

Identifying G Pulse of 1# Cylinder

II Common Fuel Rail

The fuel rail functions to distribute the fuel pressurized by fuel pump to the fuel injector of each cylinder The shape of fuel rail depends on vehicle type, and different parts are used for different vehicle types The parts included in fuel rail are fuel rail pressure sensor (Pc Sensor), pressure limiter, possibly flow buffer and pressure relief valve (for some vehicle types)

Parts and their working principles are listed in the following table:

Fuel Rail Pressure

Sensor (Pc Sensor) It detects the pressure in fuel rail

Flow Buffer

It lowers the fuel pressure pulse in fuel rail If the fuel overflows, the buffer will close the fuel passage to prevent the further fuel overflow Generally, such buffers are used together with engines for large vehicles

1 Pressure Limiter

If the pressure in fuel rail becomes abnormally high, the pressure limiter will act (open); after the pressure has fallen to the certain level, this limiter will reset (close), and the fuel released by pressure limiter will return to the fuel tank

The operating pressure of pressure limiter is subject to the vehicle type The opening pressures for valve and SINOTRUK engine are 140~230MPa and 160MPa respectively, and the minimum pressure is 30MPa

2 Fuel Rail Pressure Sensor

The fuel rail pressure sensor (Pc Sensor) is mounted on the fuel rail It detects the fuel pressure

in fuel rail, and then sends the signals to the engine ECU This sensor is a semiconducting one, which utilizes the piezoelectric effect that the resistance changes when the pressure is imposed

on the silicon elements

Pressure in Fuel Rail

Fuel Leakage Passage (to Fuel Tank) in the Case of Open Valve

Closed

Open Return

Abnormal High Pressure

Common-rail Pressure Sensors (121 and 134): 650rpm 44MPa 1.72V

2,370rpm 103MPa 2.70V

3 Flow Buffer

The flow buffer can reduce the pressure pulse in pressurizing pipe and provide the fuel to the

injector by stable pressure Besides, this buffer cuts off the fuel passage to prevent abnormal fuel

discharge when excessive fuel discharge (such as the fuel leakage in injection pipeline or fuel

injector) takes place

When the pressure pulse arises in the high-pressure pipe, the resistance produced by such a

pressure pulse during passing the measuring hole breaks the balance between fuel rail side and

fuel injector side, so that the piston will move to the fuel injector side to absorb the pressure pulse

In the presence of normal pressure pulse, the fuel injection will stop as the fuel flow reduces

When the fuel flow passing the measuring hole increases, the pressure between fuel rail and fuel

injector will gradually come into equilibrium As a result, the piston, under the effect of spring

pressure, will be pushed back to the fuel rail side However, if there is any abnormal flow

condition due to fuel leakage or similar causes on fuel injector side, the fuel having passed

through the measuring hole will lose balance Therefore, the piston will be pushed to withstand

the seat, resulting in closing of fuel passage

III Fuel Injector

According to the signals given from ECU, the fuel injector injects the pressurized fuel in fuel rail into the engine combustion chamber with the optimal injection timing, injection volume, injection rate and injection mode This fuel injector use the two-way valve (TWV) and measuring hole to control the fuel injection The TWV controls the beginning and ending of injection by means of governing the pressure in control chamber, and the measuring hole controls the injection rate in manner of limiting the opening speed of nozzle The control piston opens and closes the valve by controlling the pressure transferred from control chamber to nozzle needle When the nozzle needle valve opens, the nozzle will atomize the fuel and then inject it

1 Working Principle

To ensure the high pressure, the SINOTRUK engine is equipped with a Japanese G2 electronic fuel injector, which has been improved in many aspects, such as pressure strength, sealing performance and pressurized abrasion durability Also, its operability under high speed has been enhanced, so that more accurate injection control and multiple injections can be realized

Fuel Rail Pressure Sensor

Fuel Pump

The multiple injection is applied to the high-pressure common rail technology for the purpose of meeting Euro III Emission Standard The multiple injection means that: the main injection is divided into 1~5 times to reduce waste gas and noise emission, with the total injection volume unchanged

The fuel injector controls the fuel injection according to the fuel pressure in control chamber The TWV manages the fuel leakage in the control chamber, so as to adjust the fuel pressure in control chamber Different fuel injectors require different TWVs

No Injection

When the TWV is not energized, it cuts off the overflow passage of control chamber, so that the fuel pressures in control chamber and that applied onto the nozzle needle will be equal to the fuel rail pressure When the pressure imposed on control piston surface differs from the spring force of nozzle, the nozzle needle will close to stop the fuel injection The oil outlet measuring hole will be directly closed under the effect of spring force so as

to cut off the overflow passage of control chamber

QR Code (□ 9.9mm)

ID Code

High-pressure Fuel (from Fuel Rail)

To Fuel Tank Connector

For Example, Five-time Injection Mode

Injection

When the TWV is energized, it will be pulled up to open the overflow passage of control chamber With the overflow passage opened, the fuel will flow out of control chamber, and the pressure will fall Since the pressure in control chamber falls, the pressure at nozzle needle overcomes the downward force to push the nozzle needle upwards so as

to start the fuel injection When the fuel overflow from the control chamber, the fuel flow will be limited by the measuring hole and accordingly the nozzle will gradually open The injection rate will rise, as the nozzle opens With the current continuously imposed onto the TWV, the nozzle needle will finally reach the maximum elevation and maximum injection rate The redundant fuel will return to the fuel tank via the passage as shown in the figure

Injection End

When the energization ends, the TWV will fall to close the overflow passage of control chamber Consequently, the fuel pressure in control chamber will immediately become equal to the fuel rail pressure, and the nozzle will directly close to stop the fuel injection

Overflow

Drive Current

Control Chamber Pressure

injection Rate

Injection Rate

Control Chamber Pressure Drive Current

No Injection Injection Injection End

A high voltage is set as executive voltage in order to improve the sensitivity of fuel injector and

quicken the magnetization of electromagnetic coil as well as the response of TWV The charging

circuit in EDU or in ECU enhances the corresponding voltage of storage battery to 100V, which

will be imposed onto the fuel injector according to the signals given from ECU so as to drive the

fuel injector

3 (QR) Code

The QR (Quick Response) codes are used to improve the correction precision The QR codes

include the correction data of fuel injector, and such codes are written into the engine ECU The

QR codes largely increase the numbers of correction points for fuel injection volume so as to

greatly improve the precision of fuel injection volume

The QR Code is a kind of two-dimensional code developed by DENSO Corporation These QR

codes include not only the correction data on fuel injection volume but also the part numbers and

product numbers, and these codes can be read at a very high speed

The engine ECU identifies and corrects the fuel injector which has QR codes Therefore, it is

required to register the ID codes of fuel injector into the engine ECU after you replace the old fuel

injector or engine ECU with a new one See below for the replacement procedure of fuel injector

(you must register the ID code of new fuel injector into the engine ECU):

If the engine ECU is replaced by a new one, you must register all ID codes of fuel injectors used

in the vehicle into the new engine ECU

Replacement It is impossible for the engine ECU to identify the ID

code of new fuel injector.

It is required to register the ID codes of fuel injector into

the engine ECU Engine ECU;

Fuel Injector on the

It is required to register the ID code of fuel injector into

the new engine ECU.

Chapter III Assembling of D10 Euro III Series Diesel Engine

1 Cleaning of the Engine Body

Clean the engine body, especially clean the oil duct and water jacket with special brush, and blow them clean with compressed air, and clean each surface Wipe the cup plug hole with cloth Daub the camshaft, the cup plugs of the main and auxiliary oil duct with 271 sealing adhesive

Knock it into the cup plug with the rapping bar, and get rid of the redundant sealing adhesive on the surfaces Knock reversely the cup plug of the auxiliary oil duct at the rear end face of engine body All the cup plugs should be flat, plain and 0.20~0.40 mm below the machining surface of engine body Sleeve the connecting swivel nut of the oil inlet pipe of supercharger with sealing gasket, daub a little of thread sealant and tighten it into the screw hole of main oil duct at the rear end face of engine body

2 Assembling of the Cylinder Liner

Check the upper thrust port of cylinder liner bearing hole, trim the bur, wipe the cylinder liner bearing hole and the upper thrust port etc with cloth, and daub the cylinder liner bearing hole and the outside wall of cylinder liner thinly with a bed of molybdenum disulfide (MoS2) power

After putting the cylinder liner into the cylinder liner bearing hole and tuning it properly, press it into the engine body slowly and smoothly without too much effort by hands or special tools No automatic falling in

Check the cylinder liner after the pressing to make sure it is 0.05~0.10 mm above the surface of engine body

There must be no foreign matters

The cylinder liner is 0.05~0.10 mm above the surface of engine body

3 Reverse the cylinder body by a degree of 180 , disassemble the crankcase, knock the positioning pin into the combination parts of oil nozzle, and fit the combination parts of oil nozzle into the auxiliary oil duct of engine body by hollow bolt, red copper gasket or compounded gasket and tighten it (tightening torque 40-50 N·m)

4 Daub some oil in the camshaft bores, wipe the camshafts and fit them into the engine body

Before installing all the bearings completely, daub some cleaning oil on their journal

Install the thrust plate of camshaft on the camshaft bearing at the front end face of engine body with two 242-thread-glue-daubed bolts, and tighten it The axial clearance of camshaft should be 0.102~0.305 mm Turn the camshaft with hand to make sure there is no seizure

Oil nozzle