01 engine system lg958l

LG958L Training Material

RELIABILITY IN ACTION1

Tuesday, May 19, 2015

Chapter III Engine

Overview of Engine System

CONTENTS

Basic Structural Principle of DDE Engine Engine block group Crank-link mechanism Valve mechanism


Fuel systemCooling systemLubrication system Electronic control systemCause Judgment and Troubleshooting for Common Malfunctions of Engine System

Section I Overview of Engine System Chapter III Structural Theory of LG958L Engine System (DDE)

I. Introduction of Main Parameters I. Model Explanation

BF6M1013-22 T3-0268B Turbocharged model M Water cooling system


LG958L is equipped with Dalian Deutz BF6M1013-22T3 engine. 1KW=1.36HP

B Turbocharged model M Water cooling system F High speed 4-stroke 10 Upgrade number 6 Number of cylinders: 6 13 Stroke: 130mm 22 10X horsepower T3 Euro-III model 0268 Ordering number

2. Introduction of Main Parameters

Engine type6-cylinder, inline, water-cooled, turbocharged and inter-cooled, direct injection, and ω-shaped combustion chamber

Minimum idling speed rpm 600

Engine power (kw) 169 Compression ratio 18:1 Fuel type Diesel Cylinder pressure bar 30-38Engine rated speed 2200 r/min Working sequence of

cylinders 1-5-3-6-2-4


Cylinder bore/ stroke 108/130mm Fuel injection pump Electronically controlled monoblock pump

Minimum fuel consumption ≤210g/kW•h Fuel injector Opening pressure of 210-

230barOil cooling mode Recirculating water cooled Thermostat opening

temperature 83

Displacement 7.146 Thermostat full open temperature 95

Rotation direction Counter-clockwise, when observed towards flywheel Cylinder sleeve type Wet cylinder sleeve

II. Product Characteristics


1. The monoblock pump structure adopted is proved by European market for 12 years,featuring good product continuity and stable performance.

The electronically controlled monoblock pump is directly arranged on the cylinder block andis directly driven by camshaft so that the high pressure is established instantly within thepump. The short high pressure oil pipes feature universality and easy repair.


2. With compact structure and small volume, it’s lighter by 100~150kg comparedwith like products and features simple structure and easy repair as the repairand maintenance points are arranged on the same side of the engine.


3. With minimum fuel consumption under full load in the world’s leading level, it’slower by 5g/KWh and saves fuel by 3~5L per 100km compared with likeproducts.

Ambient noise curve of engines from industry benchmark competitors

Ambient noise curve of BF6M1013 engine


4. The engine adopts monoblock pump structure, which is located withinthe cylinder block and is directly driven by the camshaft. With goodrigidity and low noise (only 96dB under full load), it’s the model withlowest noise among the domestic industry benchmark competitors.Internal noise of cab: The internal noise meets the standard ISO 6396and is comparable with passenger cars.


5. The parts feature good universality, high serialization level, and easy matching of completevehicle. The oil sump adopts symmetric design so that positions can be swapped. The waterpump and fan are separated against mutual interference. There are multiple arrangementschemes available for the turbocharger, such as middle upward arrangement, middledownward arrangement, and rear arrangement, depending on the user’s needs.

Section II Basic Structural Principle of DDE Engine I. Engine Block Group


The engine block group includes cylinder block, cylinder sleeve, cylinder head, valve chambercover cap, and oil sump.Function of engine block group: The engine block is the primary assembly structure for engine.It bears the moving parts of the engine and the internal and external acting forces during theworking of the engine and is fitted with all kinds of accessories. Therefore, the engine block musthave enough strength to bear all kinds of acting forces under rated load or even a certainoverload. It must have enough strength to minimize the deformations of all parts during theworking of engine and have good anti-corrosion performance against coolant, lubricating oil,and flammable gas.

1. Cylinder head

The DDE engine cylinder head adopts integral structure. The cylinder head is installedon the top of the cylinder block to seal the cylinder from the top and constitute thecombustion chamber. As it comes into frequent contact with high temperature and high


combustion chamber. As it comes into frequent contact with high temperature and highpressure combusted gas, the cylinder head is subject to high thermal load andmechanical load. The cylinder head is also fitted with intake and exhaust valve seats andvalve pipe bore for installation of intake and exhaust valves and intake and exhaustpipelines.The cylinder is fixed onto the cylinder block by 18 bolts (for 4-cylinder engines) and 26bolts (for 6-cylinder engines). The cylinder head bolts must be tightened as per specifiedsequence, in order to ensure the uniform force application on the cylinder head.Before tightening the cylinder head bolts, apply engine oil onto the threaded parts.Tightening torque for cylinder head bolts: 30N.m for 1st step, 80N.m for 2nd step, and90º angle for final step.

Intake manifold

Exhaust manifold

Exhaust valveIntake valve


The cylinder head is cast with intake and exhaust ports, of which the intakeports are connected with intake pipes and the exhaust ports are connectedwith exhaust pipes. The intake and exhaust valve for every cylinder can bedetermined depending on the positions of the intake and exhaust ports.

2. Cylinder block The engine block is the basic framework for the engine. It not only bears the

acting force of high pressure and high temperature gas, but also it's fitted withalmost all engine parts. Therefore, the cylinder block must have sufficient strengthand rigidity.

(1) Depending the different mounting planes of the cylinder block and oil sump,the cylinder block is commonly classified into following three types:

Gantr

y cylin

der b

lock

Gene

ral cy

linde

r bloc

k

Tunn

el cyl

inder

block


The DDE engine adopts gantry cylinder block.

Gantr

y cylin

der b

lock

Gene

ral cy

linde

r bloc

k

Tunn

el cyl

inder

block

(2) Advantages of DDE cylinder block


The DDE cylinder block adopts German standard high strength gray cast iron. With integral noise andvibration reduction design, it reduces the noise by 3dB(A) compared with like products. The design ofcylinder block takes the easy repair and maintenance into sufficient consideration. It’s built throughbest optimized design via finite element method. The cylinder block is cast with low pressure fuel line,which is functioned as fuel inlet line of monoblock pump for non-electronically controlled engine andas fuel return line of monoblock pump for electronically controlled engine, to achieve more reasonablelayout of complete unit, prevent leakage, and preheat the fuel.The design of cylinder block takes the easy repair and maintenance into sufficient consideration sothat all external accessories, except the starter and turbocharger, are arranged on the same side ofthe engine.

(3) Structure of cylinder block

This place is the fuel line on the cylinder block and is the fuel return line of monoblockpump for


pump for electronically controlled engine.

1. Cylinder block 2. Main bearing bolts 3. Locating pin 4. Screw plug 5. Sealing gasket 6. Screw plug 7. Screw plug 8. Screw plug 9. Bushing 10. Bushing 11. Water jacket plug 13. Screw plug 14. Guide bushing 23. Guide bushing 24. Screw plug


The 1013 main oil line regulator valve is installed on the lower plane of the cylinderblock. To replace the regulator valve, tap a threaded hole with M8 screw tap andscrew in puller to take out the regulator valve at the time of disassembly. There is anopening extent of regulator valve when no engine oil pressure is available. The higherthe engine oil pressure is, the larger the opening extent is.

3. Cylinder sleeve The cylinder structure in which the cylinder is directly bored in the cylinder block isreferred to integral cylinder. The integral cylinder features good strength and rigidity andis capable of bearing high load. However, the integral cylinder features high materialrequirements and high cost. If the cylinder is manufactured into independent cylindricalparts (namely cylinder sleeve) and then installed into cylinder block.(1) Classification of cylinder sleeve For water-cooled engines, depending on whether the cylinder sleeve comes into contactwith coolant, the cylinder sleeve is classified into dry type and wet type.

Characteristics of dry type cylinder sleeve:After the cylinder sleeve is installed into the cylinder


After the cylinder sleeve is installed into the cylinderblock, its outer walls do not come into contact with thecoolant directly. Instead, its outer walls come into directcontact with the walls of cylinder block, with thin wallthickness (generally 1~3mm). It features theadvantages of integral cylinder block, namely goodstrength and rigidity. However, the machining isrelatively complicated, as the finish machining isrequired for both inner and outer surfaces, and itbrings about inconvenient disassembly and assemblyand poor heat radiation.

Characteristics of wet type cylinder sleeve:After the cylinder sleeve is installed into the cylinder block, its outerwalls come into direct contact with the coolant and the cylindersleeve only comes into contact with the cylinder block by a belt onthe top and bottom respectively, with the wall thickness generally at5~9mm. It features good heat radiation, uniform cooling, and easymachining. Generally, the finish machining is required only for innersurface and no machining is required for the outer surface cominginto contact with the coolant, featuring easy disassembly andassembly. However, its disadvantages include lower strength andrigidity against dry type cylinder sleeve and easy occurrence ofwater leakage. Therefore, some leak-proof measures shall be taken.The engine fitted on LG958L adopts wet type cylinder sleeve.


The engine fitted on LG958L adopts wet type cylinder sleeve.

(2) Measures for wear reduction of cylinder sleeveCorrect start and startup. At the cold start of diesel engine, rotate the engine for several timesto lubricate the friction surfaces before start. Then, idle run the engine for warm-up and do notdepress the throttle pedal. Do not start up the machine when the coolant temperature is lessthan 40ºC. During the running, try to maintain the diesel engine within normal temperaturerange and travel at moderate speed. Correct choice and use of lubricating oil. Choose thelubricating oil with best viscosity depending on the seasons and performance requirements ofdiesel engine. Enhance the maintenance works for fuel filter, oil filter, and air cleaner tominimize the ingress of mechanical impurity into the cylinder.

4. Cylinder gasket

(1) The cylinder gasket is installed between cylinder head and cylinder block and isfunctioned to seal the contact surface between cylinder head and cylinder blockto prevent leakage of air, water, and oil. In addition, the gap between the plane


to prevent leakage of air, water, and oil. In addition, the gap between the planeof piston crown and cylinder block is generally 1±0.1mm and can be adjusted byadding or removing cylinder gasket.

(2) Structure characteristics: The material of cylinder gasket must have certainelasticity to compensate the unevenness of the fitting surface and ensure thesealing. In addition, the cylinder gasket must have good heat resistance andpressure resistance against ablation and deformation under high temperatureand high pressure. At present, the copper sheet – cotton structure cylindergasket is mostly applied. Some engines adopt the cylinder gasket with wovenwire net or perforated steel plate framework and asbestos and rubber adhesivepressed on both sides.

(3) Calculation method for thickness of cylinder gasket for DDE engine

The DDE engine adopts metal cylinder gasket, which is classified into threethickness classes identified by the number of bores at the edge of the cylindergasket. To choose appropriate cylinder gasket, it’s required to measure the pistonprotrusion. Based on the maximum measurement of piston protrusion, choose thecylinder gasket of corresponding thickness.

Piston protrusion Mark of cylinder


Piston protrusion Mark of cylinder gasket

[0.28－0.54mm） one bore[0.54－0.64mm） two bores[0.64－0.75mm） Three bores

Measurement method for piston protrusion


[1] Remove the oil dirt from the surfaces of cylinder block, place themeasurement bar and cushion block on the sealing surface ofcrankcase, on which the cylinder sleeve is installed, and set the pointerof dial gauge to mark “0”.


[2] Place the dial gauge and measurement tool at the measuring points of piston, rotate theengine to move upward the piston, and observe the variation of dial gauge pointer. Whenthe pointer reaches maximum reading and starts to reduce, stop the rotation of engineand read the reading of the dial gauge. In such case, the reading is the piston production.

[3] At the time of measurement, choose the Ø95mm circle on the piston as the measuringpoint and keep the measuring point consistent with the direction of piston pin. All pistonsshall be measured and the maximum value shall be chosen.

The height difference between thecylinder block plane and the pistoncrown is used as the basis to determinethe thickness of the cylinder gasket. Atthe replacement of piston, measure thevalue of each piston in turn. Take themaximum value and look up the required


maximum value and look up the requiredcylinder gasket thickness S as per thediagram above.

At the time of measurement, the pistonmust at the absolute top dead center.

The height difference between cylindergasket plane and piston crown = ②-①(The range of top gap ① is 0.9~1.1mm.)

5. Oil sump


The oil sump of DDE engine adopts symmetric design to ensure easy installation. Twooil drainage plugs are fitted to ensure easy oil drainage, as the oil can be drained fromboth left and right sides. With the application of really low force, the oil sump isgenerally is stamped from thin steel sheet and its shape depends on the overallarrangement of the engine and the capacity of the engine oil. The oil drainage plug isfitted on the bottom of the oil sump. Generally, the oil drainage plug is fitted withpermanent magnet to absorb the metal particles from the lubricating oil and reducethe engine wear. The gasket is fitted on between upper and lower crankcase fittingsurfaces to prevent the leakage of lubricating oil.

5. Gear chamber cover


DEUTZ engine adopts the design thinking of separated gear chamber cover (includingrear oil seal) and flywheel housing. The flywheel housing is functioned for connectionwith complete vehicle and the gear chamber cover is functioned to seal the gearchamber and prevent the leakage of engine oil and is also functioned for ventilation ofcrankcase. This structure greatly reduces the weight and types of flywheel housing andfeature good universality. The flywheel housing is fitted with two locating sleeves (21)for orientation purpose at the installation of gear chamber cover.

II. Crank-link mechanism 1. Brief

Crankshaft timing

1st compression ring 2nd compression ring Oil control ringPiston Connecting rod bolt FlywheelSpeed sensor pulse gearConnecting rod large end lower bushing Connecting rod cap

Piston pinCirclipConnecting rod small end bushingConnecting rodConnecting rod large end upper bushingMain bearing upper bushingCrankshaftCrankshaft sprocket


The crank-link mechanism is the main part for the engine to generate and output thepower.Function: It converts the force applied by the combusted gas onto the piston crown tothe torque of crankshaft and outputs the mechanical energy.Structure: It’s composed of the piston rod group and crankshaft flywheel group.Crankshaft and main bushing: The DEUTZ engine adopts fully balanced cast steelcrankshaft, with full support.

Crankshaft timing toothed belt pulley Connecting rod capConnecting rod nutMain bearing lower bushingCrankshaft pulleyThrust plate

2. Piston rod groupPiston ring

Piston

Rod

Piston pin

Circlip

Connecting rod bearing bushing cap


Rod bushingcap

Bolt

The piston rod group includes piston, piston rings, piston pin, rod, and rodcrankshaft.Function: It transmits the power acquired from the combustion process to thecrankshaft.

(1) Piston top surface

Printed drawing number

Flywheel end mark


Printed manufacture dateWeight group mark

The manufacture date is in format of “Year-Month-Day”

year code year code month code

2001 1 2013 D 1 A

2002 2 2014 E 2 B

2003 3 2015 F 3 C

2004 4 2016 G 4 D

2005 5 2017 H 5 E

2006 6 2018 J 6 F

2007 7 2019 K 7 G

2008 8 2020 L 8 H

2009 9 2021 M 9 G

2010 A 2022 N 10 K

2011 B 2023 P 11 L

2012 C 2024 R 12 M

teamweight of the

piston(g)

A (986，994]

B (994,1002]

C (1002,1010]

(2) Piston rings


The piston rings include the 1st compression ring, 2nd compression ring, and oilcontrol ring in turn from the top to bottom. Two compression rings are mainlyfunctioned to seal the cylinder and the oil control ring is only functioned touniformly apply the lubricating oil to the cylinder walls for lubrication during thevertical movement of the piston and at the same time scrape the excessivelubricating oil into the oil sump.

Two compression rings have thedirectionality. During the installation,the compression ring marked with “top”shall face towards the piston crown.During the installation, the openings ofthree piston rings shall stagger for acertain angle with each other and shall


certain angle with each other and shallavoid the ±45º range in the directionof the piston pin.

(3) Connecting rod The mass of the connecting rod assembly (connectingrod, connecting rod small end bushing, and connectingrod bolts) shall be controlled within 1865~1965g. Theconnecting rod assembly is grouped by mass into 10groups, with the mass difference no more than 10gbetween any two neighboring groups.

Group mark

Mass (g) Group mark

Mass (g) A 1865~1875 F 1915~1925


mark markA 1865~1875 F 1915~1925B 1875~1885 G 1925~1935C 1885~1895 H 1935~1945D 1895~1905 I 1945~1955E 1905~1915 J 1955~1965

(3) Precautions for assembly of connecting rod


(1) The fracture-splitting process is adopted for the parting surface of connecting rod body cap. The fracture-splitting surface shall be free of cracking or loose metal particles. It's disallowed to reversely install theconnecting rod body and cap, or it will impair the indented junction surface.

(2) While assembling the connecting rod, the boss on the connecting rod shall face towards the flywheel end.(3) The connecting rod is stamped with number. During the assembly, pay attention to align properly to

prevent reverse installation. Once reversely installed, the indented junction surface will be impaired.(4) There is a boss on one end of the connecting rod bushing. During the assembly, align with the bushing

cap to prevent reverse installation.

3. Crankshaft flywheel group (1) Brief Main

journal Connecting rod journal

Counterbalance Crankshaft flangeFront of crankshaft

Rear of crankshaft


Crankshaft gearMain journal Lubricating orifice Connecting rod journal

lubricating orifice

The crankshaft flywheel group includes the crankshaft, flywheel, and all partsinstalled on the crankshaft (crankshaft timing gear, bushing, thrust plate, andpulley).Function: It transmits the power to the engine oil pump, water pump, aircompressor, fuel pump, fan impellor, and flywheel and outputs the power.


Crankshaft and main bushing: The DEUTZ engine adopts fully balanced cast steel crankshaft, with full support.

(2) Precautions for Assembly


[1] There are total 7 crankshaft bushing caps, which are marked with numbers1, 2, 3, 4, 5, 6, and 7 respectively counting from the flywheel end. Payattention to the sequence and do not wrongly install at the time ofinstallation.


[2] The crankcase is fitted withguide posts to ensure thesmooth installation ofcrankshaft bushing caps.

[3] The crankshaft bushing caps are fittedwith reverse installation proof boss so thatthe caps can’t be properly assembledonce reversely installed.


[4] The 2nd crankshaft bushing cap is fitted with 2 pairs of thrust plates (total 4 plates) toprevent the axial runout of crankshaft. The axial runout range of crankshaft is0.1~0.3mm. At the installation of the thrust plates, the oil line shall face towards thecrankshaft. The other two thrust plates shall be installed on the crankshaft inspacing of 180º from the above two thrust plates.

Oil groovePay attention to prevent reverse installation


[5] There are two oil grooves on the crankshaft bushings so that thelubricating oil lubricates the bushings via oil grooves. While installing thebushings, pay attention to align the external boss of bushing with thebushing cap to prevent the reverse installation.


[6] During the installation of engine oil pump, pay attention to correspond the keywithin engine oil pump to the key slot of the crankshaft and keep level themounting plane of engine oil pump with the cylinder block plane.


[7] While assembling the crankshaft, align the timing mark on the crankshaftgear with the timing mark on the camshaft. The timing mark of camshaft ison the top of camshaft gear and the timing mark of crankshaft is at thetooth space of the crankshaft gear. When it’s properly timed, the toothtop with timing mark is engaged with the tooth space with timing mark.

III. Valve mechanism

1. Brief

The rocker subassembly of engine is mainly composed of tappets, push rods, intakeand exhaust valves, and rockers.


1. Push rod 2. Tappet 3. Rocker fastening bolts 4. Rocker seat 5. Rocker 7. Washer8. Retainer 9. Fastening nut 10. Adjustment screw 11. Rocker group 12. Rocker seat13. Spring 14. Washer 15. Intake valve 16. Exhaust valve 17. Spring seat 18. Valve pipe19. Intake valve seat 20. Exhaust valve seat

2. Camshaft

1. Camshaft 2. Camshaft bushing 3. Sensing pin 4. Camshaft gear 5. Bushing 6. Idler 7. Idler 8. Guide sleeve


7. Idler 8. Guide sleeve

The valve tappets of the Deutz engine are directly driven by camshaft andthe camshaft also drives the monoblock pump. The camshaft of Deutzengine is fully supported. The BF6M engine is fitted with 6+1 bushings andBF4M engine is fitted with 4+1 bushings. All bushings are same, except thebushing near the flywheel end.

Valve Rocker and push rod

3. Main parts


Valve Rocker and push rod

Intake manifold and preheating plug Tappet

4. Arrangement of valves


The cylinder at the flywheel end is the 1st cylinder and there are 1st cylinder exhaust valve, 1stcylinder intake valve, 2nd cylinder exhaust valve, 2nd cylinder intake valve, 3rd cylinder exhaust valve,3rd cylinder intake valve, 4th cylinder exhaust valve, 4th cylinder intake valve, 5th cylinder exhaustvalve, 5th cylinder intake valve, 6th cylinder exhaust valve, and 6th cylinder intake valve in turn fromleft to right.As the engine equipped on 958L incorporates the EGR function, while adjusting the valveclearance, it’s necessary to find out the compression top dead center for valve adjustmentcylinder by cylinder. The intake valve clearance is 0.3mm and the exhaust valve clearance is 0.5mm.

IV. Fuel System 1. BriefThe fuel line pressure measuring point for low pressure chamber shall be thedownstream of fine filter outlet. The fuel pressure shall be 4.2bar at 1,500~1,899rpm,5bar at 1,900~2,300rpm, and 5bar at 2,300rpm. When measured at the cylinder blockoutlet, the measurement shall be lower than normal pressure by 1bar. When measuredat inlet of fuel delivery pump, the fuel pressure shall be no higher than -0.3bar. Thetemperature of return fuel shall not exceed 80ºC and the amount of return fuel shall bemore than 8L. 1. Fuel tank

2. Fuel line to diesel pump 3. Diesel pump 4. Fuel line to diesel filter 5. Diesel filter


5. Diesel filter6. Fuel line to fuel injection pump 7. Fuel injection pump8. Fuel line to fuel injector9. Fuel injector10. Fuel return pipe11. Fuel pipe bolt with pressure control valve 12. Fuel line of fuel return tank 13. This distance shall be as large as possible.

Fuel operation diagram

Fuel tank

Fuel-water separator

Fuel delivery pump


Fuel fine filter

Monoblock pump

Fuel injector

Fuel delivery pump Fuel return check valve

2. Main parts


Fuel delivery pump Fuel return check valve

Electronically controlled monoblock pump Fuel injector

3. Low pressure fuel line


The diesel from the diesel tank flows to the fuel delivery pump via fuel-water separator and,after being filtered by diesel filter, flows via external connector into the metal low pressure fuelline that is connected with the electronically controlled monoblock pump. Each pump isconnected with external fuel inlet pipe separately. The fuel return passage is cast on thecylinder block.As the fuel supply amount of the fuel delivery pump is more than 10 times of the fuel outletamount of the monoblock pump, a great amount of excessive fuel flows back to the dieseltank via fuel return check valve and return pipe to completely bleed the air from the fuel lineby a great amount of returning fuel and radiate the monoblock pump by a great amount ofreturning fuel flowing through the monoblock pump.

3. High pressure fuel line


The fuel in the low pressure fuel line enters into the monoblock pump. Under theaction of the monoblock pump, the high pressure fuel is formed from themonoblock pump to the fuel injector via really short high pressure fuel pipe. Whenthe pressure reaches 220bar, the fuel injector opens to inject the atomized fuel intothe combustion chamber, which mixes with the air to form flammable air mixture.

4. Electronically controlled monoblock pump (1) Brief

Advantages: The monoblock pump is one of the latesttechnologies, which ensures that the combustion is moreadaptable to the needs of working condition to achieve moresufficient combustion and higher efficiency and lower theexhaust contamination and fuel consumption. It also boastfollowing advantages: Compact structure and good rigidity, as it’s directly driven

by camshaft via tappets. Up to 1,600bar fuel injection pressure. Smaller installation space. Short and standardized high pressure fuel pipe.

Good and freely adjustable speed regulation performance


Short and standardized high pressure fuel pipe. Good and freely adjustable speed regulation performance

and applicability for engines of different applications. Easy replacement of pump.Function: Under different working conditions of the engine, itsupplies high pressure fuel at fixed timing and fixed quantity asper the requirements of complete unit so that all cylinders canfunction normally to output the required power and torque andat the same time meet the emission standard. It plays a vital rolefor the performance, working reliability, and durability of theengine and is the core part of the fuel supply system.

(2) Working Principle Injection module1 - Fuel injector body2 – Transition connecting high pressure pipe3 – High pressure fuel pipe4 – High pressure fuel pipe connector5 – Travel stop6 – Solenoid valve needle valve7 – Disc8 – Pump body9 – High pressure chamber 10 – Fuel pump plunger

15 – Solenoid valve spring16 – Valve housing with coil and magnetic iron core 17 – Output disc 18 – Intermediate disc19 – Seal ring 20 – Fuel inlet (low pressure)21 – Fuel return22 – Fixed part of fuel pump plunger23 – Plunger return spring 24 – Tappet body


When the solenoid valve is cut off, the fuel return passage opens and the monoblock pump can’t establishhigh pressure. The fuel return passage closes and the fuel pressure can rise rapidly only when the solenoidvalve is turned on. The high pressure fuel flows into the fuel injector through a really short high pressure fuelpipe for fuel injection. When the solenoid valve is cut off, the fuel return passage opens for rapid pressurerelief and the fuel injection is stopped. The power-on duration of the solenoid valve determines therecirculating fuel supply amount. The working process of electronically controlled monoblock pump ismainly classified into four stages: fuel injection process, bypass process, injection process, and unloadingprocess.

11 – Engine block 12 – Roller pin 13 – Cam14 – Spring seat 24 – Tappet body 25 – Spring seat26 – Roller body 27 – Roller

[2] Bypass process: When the plunger moves

[1] Fuel suction process: The solenoid valveis not powered on. When the plungermoves downward, the fuel pressurewithin the pump chamber is less thanthe fuel pressure of low pressure fuelline. In such case, the fuel of lowpressure system enters into the highpressure injection system via the fuelinlet on the plunger sleeve.


[2] Bypass process: When the plunger movesupward, the fuel in the plunger chamber iscompressed. However, if the solenoidvalve is still under cut-off state, the fuelpressure within the plunger chamberdepends on the opening pressure of thefuel return check valve, which is far lowerthan the opening pressure of fuel injector,so that the fuel will return to the fuel tankvia fuel return passage.

[3] Fuel injection process: During the fuel supplystroke of the plunger, when the electroniccontrol issues the fuel injection control pulseat a specific moment, based on the sensorsignals collected, and powers on theelectromagnet via drive circuit. In such case,the fuel inlet and return passages are closedand an enclosed volume is formed within theplunger chamber. Following the rise of theplunger, the fuel within the enclosed volumeis compressed and the pressure rises rapidly.When the pressure is higher than the openingpressure of the fuel injector, the needle valveopens and the fuel is injected into the


opens and the fuel is injected into thecylinder.

Note: The resistance of the solenoid coil for thesolenoid valve of monoblock valve is approximate0.9Ω. If less than 0.4Ω, the coil is probably shortcircuited. The fuel injection timing is controlled bythe power-on moment and the fuel injectionamount is calculated by the power-on duration torealize the control of fuel injection amount.

[4] Unloading process: When the controlpulse is terminated, the electromagnet iscut off and the fuel return passageopens so that the fuel overflows via fuelreturn passage, the high pressure fuelunloads to the low pressure system viavalve port, and the pressure of high


valve port, and the pressure of highpressure fuel line drops. When thepressure drops to the opening pressureof needle valve, the fuel injection iscompleted.

V. Cooling system 1. Brief


(1) The integral cooling system is adopted, featuring compact structure and easyinstallation.

(2) High reliability and low operation cost.(3) High cooling efficiency and low required power(4) 1.5bar pressure in cooling system after the running of engine. The antifreeze must

be used as the normal coolant temperature is above 100ºC. In addition, as thethinnest cast thickness of engine block water passage is only 4mm, the use ofantifreeze can prevent he blockage of water passage due to water scale.

2. Thermostat


The thermostat is functioned to change the recirculation strength of the water (routeand flow rate) depending on the engine load and water temperature. In addition, itcan shorten the hot start time of engine and reduce the fuel consumption and wearof engine parts.The DDE engine adopts paraffin thermostat, with opening temperature at 83ºC andfull opening temperature at 95ºC.

(1) Minor recirculation


Before the hot start of the cold engine, the water temperature is below 83ºC. In such case, the mainvalve closes and the bypass valve opens so that the coolant can directly flow back to the water inletof water pump via bypass pipe and is compressed into the water jacket by the water pump. In suchcase, the water only recirculates in a small scale between water jacket and water pump withoutflowing through the radiator. In such case, as the cooling strength is low, the water temperature canrise rapidly to ensure that all parts of the engine can warm up uniformly and rapidly or prevent theunder-cooling of the engine. Due to short flow route and low flow rate of the coolant, thisrecirculation is referred to as minor recirculation, namely thermostat → water pump → engineradiator → water jacket → thermostat.

(2) Major recirculation


When the water temperature within the engine rises to 95ºC, the main valve opens fully and the bypassvalve fully closes so that the coolant flows completely into the radiator. In such case, the cooling strengthis increased to drive down the water temperature or keep it from being too high. In such case, as thecoolant flow route is long with high flow rate, it’s referred to as major recirculation, namely thermostat →water pump → engine oil radiator→ water jacket → radiator→ thermostat.When the coolant within the engine is between two above-mentioned temperatures, both the main valveand bypass valve partially opens so that the major recirculation and minor recirculation of coolant coexist.In such case, the coolant recirculation is referred to as mixed recirculation.

Engine block water passage 3Minor recirculation inlet 1 Water return port 2

(3) Major and minor recirculation routes Water pump water inlet 5Major recirculation water port 4Water pump water inlet 6


Water passage 7 from water pump to engine block

Minor recirculation routeMinor recirculation routeMinor recirculation inlet 1Minor recirculation inlet 1 Water pumpWater pump Water pump outlet 5Water pump outlet 5 Water passage 7 to engine block Water passage 7 to engine block Engine oil radiator Engine oil radiator Engine block water passage 3Engine block water passage 3Cylinder head Cylinder head Water return port 2Water return port 2


Major recirculation routeMajor recirculation routeWater pump inlet 6Water pump inlet 6 Water pumpWater pump Water pump outlet 5Water pump outlet 5 Water passage 7 to engine block Water passage 7 to engine block Engine oil radiator Engine oil radiator Engine block water passage 3Engine block water passage 3Cylinder head Cylinder head Water return port 2Water return port 2Major recirculation water port 4Major recirculation water port 4Water tank radiator Water tank radiator

VI. Lubrication System 1. BriefStructure of lubrication system: Oil sump, engine oil pump, engine oilradiator, engine oil filter, pressure limiting valve, main oil passage, andengine oil pump suction pipe.Function of lubrication system: The lubrication system is functioned tocontinually convey a sufficient amount of clean engine oil at appropriatetemperature to the friction surfaces of all drive parts during the running ofthe engine and form an oil film between friction surfaces to realize fluid


the engine and form an oil film between friction surfaces to realize fluidfriction, in order to reduce the friction resistance, lower the powerconsumption, and relieve the wear of engine parts and promote theworking reliability and durability of the engine.Lubrication mode: Pressure lubrication, splash lubrication, and lubricationby lubricating grease.Functions of lubricating oil: Lubrication, cooling, cleaning, sealing, andrusting-proof.

Diagram of lubricating oil circuit


1. Oil sump 2. Intake manifold 3. Engine oil pump 3a. Oil return valve 3b. Relief valve 4. Engine oil radiator 4b. Engine oil radiator bypass valve 5. Engine oil filter 6. Main oil line 7. Main bearing 8. Connecting rod bearing 9. Camshaft bearing 10. Oil passage to fuel injector orifice 11. Fuel injection orifice for cooling of piston 12. Tappet control orifice for rocker pulse 13. Push rod 14. Rocker 15. Oil return passage to oil sump 16. Engine oil sensor 17. Oil passage to exhaust turbocharger 18. Exhaust turbocharger 19. Oil passage to compressor or hydraulic pump 20. Compressor 21. Hydraulic pump 22. Oil return passage of compressor or hydraulic pump 23. To oil sump 24. From turbocharger to crankcase

2. Engine oil pump

DEUTZ engine oil pump is of rotor type. Installed within front hood of engineand directly driven by crankshaft, it features as below:① Installed within front hood to ease the disassembly.② Directly driven by crankshaft, without additional drive parts.③ Small installation space.④ Large diameter, more teeth, and stable oil supply of pump.⑤ The rotor of oil pump is installed onto the crankshaft by three unevenly


⑤ The rotor of oil pump is installed onto the crankshaft by three unevenlydistributed keys and the pumped oil amount is controlled by the toothwidth of oil pump rotor. The oil supply amount of the oil pump is 50L/minfor 4-cylinder engine and 75L/min for 6-cylinder engine. The oil supplyamount is 90L/min for oil delivery pump of BF6M1013ECP.

Upon detection of low engine oil pressure during normal running of vehicle,check the engine oil pump. Upon detection of clear internal wear or scratch,replace the engine oil pump.

Oil pressure chamber


Oil suction chamber Oil inlet

Radiator

The engine oil radiator is built in thecoolant circuit and is under seriesconnection on the upstream of the mainoil line to control the temperature oflubricating oil by means of thetemperature of coolant. As the coolanttemperature can be controlledautomatically, the engine oil temperaturecan also be controlled to a certain extent.

3. Engine oil radiator


Radiator

Radiator cap

can also be controlled to a certain extent.Therefore, the engine oil temperature canbe controlled within normal range. Whenthe engine oil temperature is high, theengine oil is cooled by the coolant. Whenthe oil temperature is low at the start andwarm-up of the engine, the engine oilabsorbs heat from the coolant to rapidlyincrease the engine oil temperature, lowerthe flow resistance, and help thelubrication.

4. Route of lubricating oil

1. Oil sump 2. Engine oil radiator bypass

valve 3. Engine oil filter bypass

valve 4. Engine oil collector

Fan end

Engine oil filter

Engine oil


4. Engine oil collector 5. Engine oil pump 6. Supercharger 7. Main oil passage pressure

limiting valve

Engine oil radiator

1

2 34

67


5

8

Lubricating oil from engine oil pump

Lubricating oil from engine oil pump

Oil passage 1Oil passage 1

Oil passage 2Oil passage 2 Radiator Radiator Engine oil

filter element Engine oil filter element

Oil passage 3Oil passage 3

Main Oil passage 4Main Oil passage 4 Oil passage 5, for lubrication of camshaft Oil passage 5, for lubrication of camshaft

Oil passage 6 for lubrication of Oil passage 6 for lubrication of

Route of lubricating oil circuit


Oil passage 6 for lubrication of crankshaft and oil passage 7 for lubrication of connecting rod and piston

Oil passage 6 for lubrication of crankshaft and oil passage 7 for lubrication of connecting rod and piston

88 Oil passage for tappet and push rod Oil passage for tappet and push rod RockerRocker

VII. Electronic control system 1. Composition of electronic control system


Sensor Electronic control unit (ECU) Electronically controlledmonoblock pump

2. Sensors(1) In the level of complete unit, ensure that the crankshaft sensor, camshaft

sensor, and engine oil pressure sensor work normally, or the completeunit can’t be started.

Crankshaft speed sensor

Camshaft speed sensorCoolant temperature sensor

Turbocharged air temperature sensor

Fuel temperature sensor


Air pressure sensor, within ECU

Turbocharged air pressure sensor

Engine oil pressure sensor Throttle pedal position sensor

(2) Function of camshaft speed sensor:

The crankshaft sensor needs 15s to find out the top dead center.


dead center.

At the time of start, the determination of the 1st cylinder compression top dead center can be taken as the reserved function of crankshaft speed sensor.

(3) Crankshaft speed sensor


The crankshaft speed sensor is installed on the front of the engine.By measuring the tooth signal on the engine flywheel, it provides instantspeed of engine to the ECU for accurate timing and fuel amount control onthe engine.

(4) Fuel temperature/water temperature sensor


The water temperature/fuel temperature sensor provides the enginecoolant/fuel temperature signal to the ECU and its sensing unit is a negativetemperature coefficient thermistor. The ECU continually collects the real-timewater temperature and fuel temperature to correct the fuel injection amount.

(4) Fuel temperature/water temperature sensor

RELIABILITY IN ACTION76 76

The intake pressure temperature sensor provides to the ECU the intaketemperature and intake pressure information at the downstream of engine-cooler. The pressure sensing unit is a silicone diaphragm and the temperaturesensing unit is a negative temperature coefficient thermistor. The ECU collectsthe intake pressure and temperature information to correct the fuel injectionamount.

(5) Engine oil pressure sensor


This sensor real-time detects the engine oil pressure information andtransmits to the ECU. When the engine oil pressure is out of normal range,the ECU will restrain the engine power or control the flameout of the engine.

3. Main functions of ECU

(1) Start controlFor an engine, to ensure the start reliability andstart smoke number emission requirements,the fuel injection timing and start torque mustbe set as per the method below:Fuel injection timing = f (speed, fuel injectionamount, and coolant temperature)Start torque = f (speed, coolant temperature,


Start torque = f (speed, coolant temperature,and start time).The start control function is under activatedstate, till the engine speed exceeds the startend speed and the engine enters idling control.The driver can operate the engine only underthe idling control state. The start end speed issubject to the coolant temperature andatmospheric pressure.

(2) Fuel injection timing adjustmentThe adjustment of fuel injection timing is intended to meet the emissionregulations and fuel economy requirements as well as consider the cold startand low noise. The adjustment of fuel injection timing is related to theengine performance and additional correction.Fuel injection timing = f (speed, fuel injection amount, cooling temperature,intake pressure, and atmospheric pressure)


(3) Malfunction DiagnosisThe electronic control unit incorporates the real-time self-diagnosis function.Upon detection of malfunction, the ECU will save the malfunctioninformation and current environmental information into the ECU. At thesame time, the malfunction indicator lamp on the instrument panel flashesto remind the driver of getting repaired by the service station. At the servicestation, the repair personnel will connect special diagnostic tool to the ECUand read out the malfunction information.

(4) Cold start auxiliary controlUnder cold temperature, to improve the cold start performance of theengine, the ECU will determine whether the intake preheating is requiredand the required preheating duration depending on the current enginetemperature, which is realized through the control on the intake preheatingrelay.


(5) Engine protection functionIt’s intended to protect the engine under certain extreme conditions.Under the working conditions such as over-high coolant temperature andunder-low engine oil pressure, the engine power will be lowered or it willeven lead to engine flameout, in order to protect the engine.

Section III Cause Judgment and Troubleshooting for Common Malfunctions of Engine System

I. Diagnosis and troubleshooting procedure for malfunctions of DDE engine


1. Thoroughly consider the malfunction cause by considering the engine as an integralunit.

2. Thoroughly understand the information from the operator: Abnormal noise, workingcondition and environment, change of oil pressure or water temperature, abnormaldust or smoke at occurrence of malfunction, consumptions of engine oil, fuel, andcoolant and their recent changes, smoke density, fuel in use, presence of enginesurge during idling or full speed running, presence of long-term idling, recenttemporary repair and repair information, previous occurrence of similar malfunction,information of part replacement, and status after previous treatment.

3. Conduct necessary checking: Enginecleanliness, belt tension, presenceof external leakage of engine oil,fuel, or water, levels of engine oil,water, and fuel, engine sound,presence of jitter, and presence ofsmell, carbon deposit, oil mud, andother abnormality beneath therocker cap at the time of


rocker cap at the time ofdisassembly.

4. Conduct correct analysis.5. Conduct correct repairs.6. Verify whether the repairs fulfilled

actually solve the malfunction.

II. Diagnosis and troubleshooting principle for malfunctions of engine

1. Upon detection of malfunction, firstly check whether the operation andmaintenance instructions are strictly followed and check for presence of


maintenance instructions are strictly followed and check for presence ofsubstituting the maintenance with repair.

2. Poorly manufactured parts (such as hollow filter element), especially thecounterfeit products procured due to temptation of cheap prices, will greatlyshorten the service life of diesel engine.

3. At the occurrence of malfunction, exclude one by onefrom simpleness to difficulty.

4. Do not replace any part easily before the malfunctioncause is found.

5. Pay attention to disconnect the battery during repair, inorder to prevent the start of engine.

III. Analysis of malfunction cases 1. Cause for difficult start or start failure (1) Malfunction of starter electric lock (2) The temperature is less than start limit temperature (3) Malfunction of starter interlock (4) Blockage of fuel delivery pump inlet passage (5) Working failure of cooling fan/broken or loose belt (belt-driven fuel delivery pump) (6) Battery depletion or malfunction (7) Loose or oxidized wires of starter motor (8) Damage or engagement failure of starter motor


(8) Damage or engagement failure of starter motor (9) Incorrect valve clearance (10) Leakage of high pressure fuel pipe (11) Malfunction of preheating plug (12) Damage of fuel injector (13) Air content in diesel system (14) Dirty diesel filter and diesel strainer (15) Incorrect engine oil grade or viscosity (16) Disqualified diesel (16) No signal from sensor to ECU (18) Malfunction of starter relay (19) ECU malfunction

Sensor input: 1. Crankshaft position 2. Camshaft position 3. Coolant temperature 4. Intake temperature and pressure 5. Engine oil pressure Electronic control unitECUSetting point:Foot throttle positionsensorHand throttle positionsensorFunctional selection switchPort: Power supply

Function block diagram of system

[1] Functional block diagram of starter system


Actuator: Electronically controlled monoblock pump Power supply Diagnostic port CAN bus Display functions: Speed Torque Warning signal Malfunction indicator lamp

[2] Fuel line judgment

Malfunction symptom: While driving the rotation of engine with starter, there is noexhaust gas or start symptom of the engine.Judgment method: Cylinder interruption method.1. Outflow of diesel: It indicates that the malfunction occurs at the high pressure

fuel line.2. Air in out-flown diesel: The malfunction occurs in low pressure fuel line or fuel

return line.3. No outflow of diesel: The malfunction occurs at low pressure fuel line.


No outflow of diesel after cylinder interruption

Check fan belt

Observe fuel amount

Leakage of low pressure fuel line

Blocked

Replace if broken

Adjust if loose

Normal

Replace if no rotation


Observe fuel amount

Leakage of low pressure fuel line

Blocked

Replace if broken

Adjust if looseCheck fuel delivery pump pulley

Replace if no rotation Normal

Repair

Check fuel delivery pump Outflow of fuel after cylinder interruption No pressure

Low fuel supply of fuel delivery pump

Pressure of manual fuel supply

Check and adjust regulator valve

Wear of housing

Soft check valve spring

Stagnation of fuel return check valve

Broken check valve spring


Low fuel supply of fuel delivery pump

Pressure of manual fuel supply

Check and adjust regulator valve

Wear of housing

Soft check valve spring

Stagnation of fuel return check valve

Broken check valve spring

II. Unstable running or start failure (1) Working failure of cooling fan/broken or loose belt (belt-driven fuel

delivery pump) (2) Incorrect valve clearance(3) Leakage of high pressure fuel pipe (4) Damage of fuel injector(5) Air content in diesel system (6) Blockage of diesel filter and diesel strainer


(6) Blockage of diesel filter and diesel strainer (7) Disqualified diesel (8) ECU malfunction (9) Malfunction of speed sensor

III. Insufficient engine power (1) Check the maximum idling speed with speedometerDepending on the configuration of the engine, the maximum idling speed shall behigher than the rated speed by 6~8%. The basic calculation equation is as below:Maximum idling speed = Rated speed × 1.07If the maximum idling speed is insufficient, check whether the throttle pedal can reachthe maximum throttle position.(2) Check the fuel injector for presence of leak through or cavitation due to insufficientprimary fuel line pressure.(3) Check the low pressure fuel line system. The insufficient pressure of low pressurefuel line will directly lead to insufficient power or ablation of fuel injector.


fuel line will directly lead to insufficient power or ablation of fuel injector.The minimum fuel supply pressure of low pressure fuel line in 5bar system (unloaded):

1500-1899/min >4.2bar 1900-2500/min > 5.0bar>2500/min >5.3bar

The pressure measuring point of the low pressure fuel line shall be the downstream ofthe fuel outlet of the fine filter (namely at the fuel inlet of crankcase). If nomeasurement space is available in this point, measure at the upstream of the fuelreturn valve (namely at the fuel outlet of the crankcase). Caution: Under rated speed,the pressure measured at the fuel outlet of crankcase is lower than the fuel pressure atfuel inlet of crankcase by approximate 1.0bar.

Causes for insufficient pressure of lowpressure fuel line:- Blockage of fuel strainer and fine filter.- Failure of fuel return valve.- Over-high flow resistance in fuel delivery

pipeline from fuel tank to fuel deliverypump.


pump.- Sufficient fuel supply pressure in fuel delivery pump.- Excessive flow resistance in fuel delivery pipeline from fuel return valve

to fuel tank. In event of excessive resistance, the fuel return amount willbe insufficient and the fuel temperature will rise (the fuel temperatureshall not exceed 80ºC).

Checking Method:(1) Provided that the filter element is not blocked, if the fuel pressure can’t

be reached, check or replace fuel return valve.(2) If the pressure is still insufficient, check the fuel delivery line for presence

of over-high flow resistance. Method:Supply the fuel on the upstream of fuel delivery pump directly with a fuelbarrel, in order to determine the over-high resistance due to fuel supplypipeline and strainer from the fuel tank to fuel delivery pump.Requirement: The fuel pipe inside diameter on the upstream of the fuel


Requirement: The fuel pipe inside diameter on the upstream of the fueldelivery pump shall be no less than 12mm and the fuel pressure at the inletof fuel delivery pump during the maximum idling speed shall be more than -0.5bar (or -0.35bar for Euro-II compliant engines).(3) If the pressure is still insufficient, check the fuel return amount. Method:Disassemble the fuel return end of the fuel return pipe from the fuel tank andinsert into an empty barrel. Measure the fuel return amount of the engineunder the maximum idling speed for 1min. The amount shall be above 8L.

IV. Black smokeRoot cause: Due to incomplete combustion of diesel, the incompletelycombusted carbon forms free carbon, which is floating within the combustedgas and is exhausted along with the exhaust gas to form black smoke.

Malfunction Cause:(1) Blockage of air cleaner and excessive intake

resistance. 。(2) Excessive fuel supply amount of fuel injection


(2) Excessive fuel supply amount of fuel injectionpump or over-high uneven fuel supply amongcylinders.

(3) Blockage of inter-cooler.(4) Poor injection of fuel injector(5) Low cylinder pressure.(6) Poor quality of diesel.(7) Insufficient cylinder pressure.

(2) If the air cleaner is normal and the black smoke is present during idling of thediesel engine, it indicates excessive fuel supply amount under idling condition.Check the fuel injection pump.

(3) If the fuel supply of the fuel injection pump is normal, check the fuel supplytiming of the fuel injection pump.

Diagnosis and troubleshooting method for black smoke:(1) Disassemble the air cleaner and check and clean the

inter-cooler.If the black smoke of diesel engine disappears, itindicates that the air cleaner is too dirty and shall becleaned.


timing of the fuel injection pump.(4) If the fuel supply timing is correct, check the working condition of cylinders by

single cylinder interruption method. If the speed variation is not obvious andthe black smoke symptom disappears after the fuel interruption of certaincylinder, it indicates the poor working of this cylinder, probably the excessivefuel supply amount of branch pump, poor mist injection quality of fuel injector,or under-low cylinder pressure. After the cause is determined, resolve thecause.

(5) If no problem is detected in above-mentioned items, the diesel quality isprobably too bad, which leads to incomplete combustion. Replace the diesel.

V. White smoke 1. Cause: The diesel within the combustion chamber is vaporized and not

combusted and is drained in milk white from the exhaust pipe or the watercontent in the diesel is vaporized in the cylinder to form steam, which isexhausted in white from the exhaust pipe.

Malfunction Cause(1) Water content in diesel or water leakage due to burst cylinder gasket or

cracked cylinder head or cylinder block, leading to water ingress of cylinder.(2) Low cylinder pressure.


(2) Low cylinder pressure.(3) Under-low working temperature.(4) Poor injection quality of fuel injector.(5) Poor diesel quality.(6) Late fuel supply moment of fuel injection

pump.

Diagnosis and troubleshooting method for while smoke:(1) During the running of diesel engine, loosen the air bleeding screw or high pressure fuel

pipe connector on the monoblock pump and check the fuel flow for presence of waterdrops. IF no water drop is present, it indicates that the white smoke in exhaust pipe iscaused by the water content in diesel. Fully drain the water from fuel tank, diesel filter,and high and low pressure fuel lines.

(2) If there is no water in diesel, open the water tank and observe the water tank forpresence of air bubble. If the air bubble is present, it indicates the ingress of coolant intothe cylinder. Disassemble the cylinder head, find out the malfunction portion, and repairor replace.

(3) If there is no ingress of water into cylinder, check the cylinder pressure. If the cylinderpressure is too low, check and repair.


pressure is too low, check and repair.(4) While traveling in winter, if the diesel engine is frequently working under low

temperature, it will lead to presence of white smoke in exhaust pipe. Check whether theshutters are closed securely and the insulation sleeve is good. Otherwise, the repair isrequired.

(5) If no problem is detected in above-mentioned items, check the fuel injection quality ofthe fuel injector.

(6) If the fuel injection quality meets the requirements, check the fuel supply timing andadjust as specified. The diesel quality is of certain influence on the white smoke of dieselengine exhaust pipe. If necessary, replace with new fuel for comparison testing.

VI. Blue smoke A great amount of engine oil that enters into the combustion chamber is vaporized to oil gas and exhausted from exhaust pipe before being combusted. Malfunction Cause: (1) Excessive engine oil in oil sump. (2) Penetration of engine oil into combustion chamber due to damaged oil seal

of turbocharger. (3) Serious permeation of engine oil in cylinder. (4) Wear of valve stem and pipe, leading to excessive gap and failure of valve

pipe seal.


pipe seal.

Diagnosis and troubleshooting method for blue smoke:(1) Check the engine oil level in oil sump. If above specified level, drain the

excessive engine oil.(2) If the engine oil level is normal, disassemble the fuel injector and check

the oil dirt and carbon deposit of the fuel injector. In event of serious oildirt and carbon deposit, it indicates the serious permeation of engine oilon cylinder or excessive gap of valve stem and pipe. Disassemble thecylinder head to find out the cause and resolve the malfunction.

(3) Check the working status of seal rings of intake and exhaust valve pipes.(4) Check the sealing status of turbocharger.


(4) Check the sealing status of turbocharger.

VII. Engine oil pressure warning

Step 1 Check the oil sump for under-low (over-high) oil level or shortage of oil and check for qualified engine oil trademark. ；

Step 2 Check the engine oil filter and cooler for excessive resistance.

Step 3 Check for over-high water temperature of cooling system and check for over-high engine oil temperature. Check turbocharger, strainer, engine oil pipeline, and connector gasket for


Step 4 Check turbocharger, strainer, engine oil pipeline, and connector gasket for presence of blockage or rupture.

Step 5 Check the pressure limiting valve of main oil line for excessive or insufficient adjustment.

Step 6Check the bushings for excessive gap or damage, check whether the engine working hours reach the overhaul period, and check the parts for serious wear.

VIII. Over-high water temperature

Step 1The water temperature is high when the diesel engine runs under high load. Check whether the oil sump level, water tank level, and water pump belt are normal.

Step 2 Check whether the thermostat and connecting water pipes are normal.

Step 3 Check the water temperature gauge and water temperature sensor for normal functioning.

Step 4 The checking of fan found out that the external surfaces of the water tank are really dirty and the radiator port is completely blocked by dirt. ；


IX. Oil-water mixture 1. Damage of engine oil radiator sealing

gasket or engine oil radiator. 2. Damage of cylinder gasket. 3. Cracking and blister of cylinder block.

really dirty and the radiator port is completely blocked by dirt. ；

THE THE THE THE


THE THE

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01 engine system lg958l

Documents

engine system chapter

engine power

engine rated speed

fuel injection pump

monoblock pump structure

model withlowest noise

low noise

withinthe cylinder block