Guangzhou GDF 8320

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OPERATING MANUALFOR 8320 MARINE DIESEL ENGINE

GUANGZHOU DIESEL ENGINE FACTORYTHE PEOPLE'S REPUBLIC OF CHINA

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CONTENT

CONTENTSGoNTENT.. . . . . . . . . . . . . . . . . . .0_,1ATTENT|ON.. . . . . . . . . . . . . . .0___4PREFACE... . . . . . . . . . . . . . . . .0_5Instal lat ion Arrangement of Model 8320 Marine Engine.. . . . . . . . ' . . . . , . . . . . . . . . . . .0-7Propulsion Character ist ic curves of Model 8320 Marine Engine.. . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . 0-g

CHAPTER 1 MAiN SPECIFICATIONS OF THE ENGINE AND ITS ACCESSORIES...,.,,.,,.,......1_11.1 Main specification of the Engine...... . . . . . . . . . . . . . . . 1 - 11 .2 Spec i f i ca t i ono fma inaccesso r iesandsys temda ta ' . ' . . . . . . . , . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 -21-3 Main technical data of the engine.. . . . . - . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . .1-s

1 .3 .1 P ressu re . . . . . ' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1_51.3.2 Temperature,. , . . . . . . . . . . . . .1_51.3.3 Pret ightening Torque for Major Botts . . . . . . . . . . . . . . . . . . . . . . . . .1__S1.3.4 Weights of l \ r la jor Components Needed for Overhaul. . . . . . . . . . . . . . . . . . . . . . . . . . .1_71.3.5 Pressure for l lydraul ic Test of MajorComponent. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-71 .3 .6 Fue l and Lube O i l Recommended . - . . . . . . . . . . . . . ' . . . . . . . . . . - . 1 -7'1.3.7 Refreshing Interval of Lube Oi l . . ' . . . . ' . . . . . . . . . . . . . . . . . . . . . . . . .1-B1.3.8 The fitting clearances and Wear limits of main parts of the engine...... ... 1-9

CHAPTER 2 OUTLINE OF MOOEL 8320 MAIN MARINE OIESEL ENGINE, .........-.....-...,...,2-1

CHAPTER 3 ENGTNE MA|N COMPONENT,. . . . . . . . . . . . . . . . . . . .3_13. ' l Main moving Parts. . . . . . . . . . . . . . . .3-1

3.1-1 Nodular grapr. . r i ' ; Cast l ron crankshaft . . . . . . . . . . . . . . . . . . . . . . . .3-13.1.2 Electroslag S".rel t ing Cast ing Steel Crankshaft , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-23.1.3 Piston and Connect ing Rod Assembly. . . . . . . . . . . . . . . . . . . . . . . .3-g

3 .2 Ma in S ta t i ona ry Pa r t s . . . . ' . . . . . . . . . . ' . . . . . . . . . . . . . . . . 3 293.2.1 Cyl inder Block, Bedplate and Main Bearin9.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-293.2.2 Cyl inder Liner. -- . - . . . - . . . . . . . . . . . . . . . . . . . .3-363.2.3 Cyl inder Head and i ts Attachments' . ' . . . . . . . . . . . . . . . . . . . . . . . .3-38

3.3 Valve Gear. . . . . . . . . . . . . . . . . . . . . . . .3-473.3.1 Camshaft . . . . . . . . . . . .3-423-3.2 Camshaft Dr iv ing Gear. . . . . . . . . . . . . . . . . .3-493.3.3 Tappets for In letand Exhaust Valve' . ' . . . . . . . . . . . . . . . . . . . . . . . .3-S03 .3 ,4 Rocke r A rm. - - . . . " . . . . ' . . . . . . . ' . . . . . . . . . . . . 3 -S13.3.5 Adjustment c\i 'ie Cold Valve Clearance-' ...................3*S2

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CONTENT

CHAPTER 4 FUEL SYSTEM........ ""'""""4-14.1 Fuel t ransfer Pump"" """"" '4-24.2 F uel Fi l ter"""""" "" ' """"" '4-44.3 Fuel Injection Pump"" """""'4-44.4 Fuel Injection Tappet" """""'4--S4.5 Control Linkage for the Fuel jn ject ion Pump"""""""" """"""" '4-74.6 Fuel In jector""""""" """ " '4-1o4.7 Maintenance and overhaul of the Fuel System"". ' """ ' """" ' " '4-11

4.7.1 Escaping Air from the fuel system""""""" ""' "' "' "' 4-114.7.2 Washing of t i 'e Fuel Fi l ter"""" ' -""" ' """"""""""" '4-124.7.3 Overhaul of the Fuel Del ivery Pump"" """"""""" ' "4-124.7.4 Maintenance and Overhaul of the fuel injection Pump.'""""""""""".''4-134.7.5 Checking the Advanced Angle for Fuel lniection"""""" ".'"4-164.7,6 Adjusting of the Advanced Angle for Fuel Injection"""""""""""""""4-174.7.7 lvlaintenance and Overhaul of the Fuel Injector"-""""""""""-"".'"""4-'19

GHAPTER 5 LUBRTCATTNG SYSTEM... . . . . . . . . . """""""" '5-15.1 Lube Oi l Pump"""""""" "" . ' """" . ' """-"""5-35.2 Lube oi l Pressure Regulat ing Va|ve"""""""" """"""""-"""" '5-55.3 Lube Oi l Fi l ter"""""" ' "" """5-75.4 Manual Oi l ing"""""""" """5 7

CHAPTER 6 COOLTNG SYSTEM'. ' . . ' . . . . ' """"""""""- ' - '6-16.1 Cool ing Water Pump""" ' """ '6-36,2 Lube oi l coolerand fresh water coo|er"""""""""" . ' """"""" '6-56.3 Supercharging Air Cooler""" " ' - """"""""""6-8

GHAPTER 7 STARTTNG SYSTEM... . ' . . , . . . """"""""""""7-17 i An Distributor" "" "" """"""7-27.2 Main Starting Valve"'.' """""7 37.3 Sbrting Control Valve""" """'7-57.4 Start ing Valve""""""" ' " """"""""" ' -""" '7--7,5 Starting Accelerator"" """""""-"'-""" """7-77.6 Fuel Limiter ' . . """"" """"" '7 77.7 Air Filter""' " " " .'""7-9

7.8 Air Bott le"" """""""" """" '7--9

CHAPTER I CONTROL SYSTEM.' . . ' . . , . """"" """"""""8-18.1 Principle of ControlAction at local engine"" """8-18.2 Control Box""""""""" " ' ' " " '8 38.3 Value f ixer. ' """""""" ' " ' ' - ""8-5

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CONTENT

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CHAPTER 9 GOVERNOR. OVERSPEED LIMITER AND EMERGENCY BRAKE.. . . . . . . . . " . . '9-19,1 Driving Gear for the GcvernoT""" " "" " "" """'9-19.2 Variable Speed Hydraulic Governor"""""' """'9-39.3 Oversoeed l imiter ' . . . . . ' . . ' . " ' """""""""""""9-89.4 Emergency Brake" ' - ' . """"" """"""""""""9-10

CHAPTER 10 EXHAUST GASTURBOCHARGING SYSTEM .. . . ' ' ' ' ' " . . " . . ' '10-110.1 Turbocharger ' . ' . . ' . . . . . . . . . . "" ' """""""""""1G*210 .2 Exhaus t A i r o ipes . . . . ' . " " " " ' - " " " " " " " " " " ' 10 -210.3 Air In let pipes. ' . . . . . . . . """" '1O-210.4 Air cooler.' " " " "' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' 1 0-310.5 Air-Water SeDarator. . , "" " " ' """"""""""" ' 1G-3

GHAPTER 11 MONITORTNG AND ALARM DEVICES.'.'...'.. . ' . ' . ' ' . ' . . ' . . . . . . . . . 1 1 - I11.1 Local Instrumentat ion."""""""" ' """""""11-111.2 Alarming Device.. . . . . . . """ " """ " " " "" " """ 11 2

CHAPTER 12 OPERATION OF THE ENGINE . , . . . . . . . . . . " ' " .12-112.1 Working Fluids.- . . . . . . . . "" . ' " """""""" " """ 12-112.2 Prepe'alion for SErting the Engine After Long Period Stoppage""" "" " """ """ 12-412.3 Starting"" """""""""""'12---612.4 Maintenance During Engine Running"""""" """""""""""12-712 .5 Shu t Down o f t he eng ine " " " . ' " " " " - . ' . ' ' " " "12 g12.6 Emergency Operat ion of the Diesel Engine. ' . ' " """" """""""12-g12.7 Emeryency Stopping -[urbocharger During Engine Runnin9"""""" """""""'12-1012.8 Water Washing of the Turbocharger Compressor"" """"""12 1012.9 Water Washing of the Turbine""' """"""'12-1312.10 Technical Maintenance Schedule for the Engine"""" . ' "" """"""12- '1512.1'1 Engine Storage and Reuse"""""""' """'12*20

0HAPTER 13 TROUBLE SHOOTTNG AND REMED|ES.. . . . . . , . . . . . . . . . . ' . ' . . ' . . . .13-1CHAPTER 14 SPEC|AL TOOLS.-. ' . . . . ' . . . . ' . , . ' .14*1

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PREFACE

This operating manual is for 8320 marine Diesel engine (irreversible). lt introducesin some detail the main components and main systems of the engine, provides someexperience in engine operation ard maintenance, as well as remedies for engine troubles.

There is a separated volume for the turbocharger.All manuals should be handed over to the operators, so as fo ensure them a better

understanding and master of the engine configuration and related technical data, to reach arational maintenance of the engine, ensuring the engine being operated in normalconditions, and reducing troubles, getting more safety in seruice and longer lifetime of theengine.

It may make a difference befuveen the actual components (which are generally |essimportant) and the ones described hereafter, as a result of continuous product improvementand change of some accessorles. However, additional remarks will be provided if evidentdifference should exist.

Any comments and suggestions concerning this operation manual are welcome.

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Installation Arrangement of Model 8320 Marine Engine

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Propeller Characteristic Curves of Model 8320ZCd-4 Marine Engine

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2100

tB00

1600

1100 -=ir1200

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ztO -rr 400 500 515 (,f. / V1Propeller Characteristic Curves of Model 83202Cd-6 Marane Engine

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800

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200

in)

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MAIN SPECIFICATIONS OF THE ENGINE AND ITSACCESSORIES

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Designation unit Specifi cation or parameter

8320ZCd-4 | 8320ZCd-6 | 8320ZCd-8Steady-state speed regulation %

MAIN SPECIFICAiIONS OF THE ENGINE AND ITSACCESSORIES

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1.3 MAIN TECHNICAL DATA OF THE ENGINE

1.3.1 PRESSURECompressed Pressure of cylinders (idle)

Starting air pressure

Air pressure for the local control system

Air pressure for the remote cciitrol system

Open pressure of cylinder safety valve(at which the safety valve is opened) ' .

Open pressure of air bottle safety valve--(at which the safety valve is opened) --..--

Open pressure of the safety valve of thelow-pressure air boftle for remote control system (atwhich the safety valve is opened)

Lube oil pressure (in the main oil passage)

Lube oil pressure (at the camshaft bearingand the valve mechanism)

Low lube oil pressure (alarm)

Tool low lube oil pressure (engine stop ) -.

Working pressure of internal circulating water

Pressure of fuel oil delivery

Pressure of HFO deliverv

3.1-3 .8MPa

't.47-2.94MPa

0.6MPa

0.6MPa

16.5MPa

. 3 .14MPa

0.7MPa

0.45-0.55MPa

0.1-0 .3MPa

0.2MPa

0.12MPa

0.06-0.23MPa

0.1-0 .1sMPa

0.4-0.5MPa

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1.3.2 TEMPERATURESupercharging air temperature after intercooler 45C -50C

Exhaust air temperature after the cylinder head {450C(engine operated on light fuel rt:l)

Exhaust air temperature after the cylinder head


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1.3.3 PRETIGHTENING TOIIQUE FOR MAJOR BOLTSDesignation Specification Pretightening Torque (N.m)Connecting rod bolt M27X2 750-800Main bearingbolt M3OX2 736-834Flywheel bolt M3OX2 490-588Bolt for rocker arm seat M24X2 295-344Bolts for connecting engineblock with bedolate

M20X2M22X2

137-176206-255

Bolts for the crankshaftresilient gear

M20X2 159-196Bolts for the damper M2OX2 159-196

Cylinder head bolts M33X2Hydraul icPressureofstretcher

8320ZCd-4:50-53 MPa8320ZCd-6:54-56 MPa8320ZCd-8i57-60 MPa

Tie-rod bolts M39X2 Hydraulic pressure of strelcher86MPa

Bolts for crankshaftcounterbalance M3OX2 800

Recommended toroue forother bolts

M10X1 .5M12X1.75M14X2M16X2M18X2.5

14-2224-3838-6059-9482-130

1.3.4. Weights of main components needed for overhaul

DESIGNATION WEIGHT (ks)

piston-connecting rod assemblycylinder headcyl inder l iner

turbochargerflywheel

235205160870938

1 .3.5. Pressure of raulic Test of Main ComCooling water chambei of Cyl inder Head,Turborcharger, Engine Block and Coolers

Air Chamber of Cylinder Head, and Air Bottle

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1.3.6

1.3.7

FUELAND LUBE OIL RECOMMENDED1. FUEL OIL

Light diesel fuels (G8252-2000)180cSU50Cheavy diesel oil (The performance refers to (Points forAttention to HFO Operation for Series 320 Engines) )

2 . LUBE OIL40CD diesel engine lube oil (G811122-1997)4030 lube oil with high T.B.N (when the engine is operated on HFO,see (Points forAttention to HFO Operation for Series 320Engines) ).

3. LUBE OIL FOR THE TURBOCHARGERRust Prevention Steam Turbine Oil 46# (G811120-1989).

4 . LUBE OIL FORTHE GOVERENORTurbine oil 22#

Refreshing Interval For lube oil

For the new diesel engine, the first time to refresh the lube oil shall beafter 300 operating hours .The recommended Lube Oil Refreshing Interval (the Engine isoperated on light diesel oil with a lube oil circulating flow of 1.36 L/kW;Otherwise the interval should be changed accordingly, Reasonablerefreshing Interval should then be based upon Checking Results of OilSampling) is every 2500 operating hours.lf the engine is operated on HFO, the recommended Lube Oilrefreshing inte|val refers to the (( Points for Attention to HFOOperation for Serres 320 Engines) .

The refreshing lube oil interval for the turbocharger is every 500operating hours.The refreshing lube oil interval for the governor is every 2500 operatingnouts.

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MAJOR SPECIFICATIONS & MAIN TECHNICAL DATAOF THE ENGINE AND ACCESSORIES

1.3.8 THE FITTING CLEARANCE AND WEAR LIMITSOF MAIN PARTS OF THE ENGINE

(in mm, measured at 20C of ambient temperature)

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DESIGNATION

OF

ASSEMBLY

POStTtONS

OR

ITIIATCHED PARTS

DIMENSIONS

OF

NEWPARTS

CLEARANCEIN NEW

ASSEMBLY

PERMISSIBLE

CLEARANCE

WEAR

LIMIT

Crankshaft

Main iournal

Main bearing

@250 ffi{O=

O250 {o

0.22-0.30 o.45

Crank-pin

Connecting rodoeanng

-oGts(D250 -od+OE(D250 .|oG

0.20-0.28 0.45

Axial clearancebetween thecrankshaft andthe thrust collar

1.6-2.0 2.2

Crank-web

Deflection

After crankshaftbeing coupled toshafting

See chapter 3

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MAJOR SPECIFiCATIONS & MAIN TECHNICAL DATAOF THE EhIGINE AND ACCESSORIES

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DESIGNATION

OFASSEMBLY

POSITIONS OR

MATCHED PARTS

DIMENSIONS

OF NEWPARTS

CLEARACEIN NEWASSEMBLY

PERMISSIBLE

CLEARANCE

WEAR

LIMIT

Nodularg rap hite

Cast iron

Piston

Cylinder liner

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o32o6

piston o31e 68-0903

o31e.4o-o9ospiston

prsronIII o318.70-0%5

0.30-0.37 135

o320.6

0318 .6

Piston ring

1"t compression ringgroove

1*' compresgion ring(chromium plated)

^ rotlb 4Cl(E

^ -xxrO -CICE

0.13-0.165 0.30

2nd, and 3d

compressron rlnggrooves

2nd, and 3d

compression rings

^ {t(Eb {alct

^ -octO -C'CE

0.011-0.135 0.30

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DESIGNATIONOF

ASSEMBLY

POSITIONSOR

MATGHED PARTS

DIMENSIONSOF

NEW PARTS


PERMISSIBLECLEARANCE

WEARLIMIT

Piston ring

4th compressiorr ringg roovescraper ring

10

10

18 89-B oz

0.07-0.1 1 0_30

Gap clearance of '1stcompression ring fitted inthe cylinder liner

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Gap clearance of 2nd ,and 3rd compression ringfitted in the cylinder linerGap clearance of thescraper ring fitted in thecylinder liner

1 .3 -1 .5

0 .9 "1 .3

3.0

3.0

Piston pin

Piston pin Connectingrod small end bushDiameter of the seat hole

{'GE0'135 {octo135

30135

&

0.195-0.2430.048-0.073

0.400.20

Connecting rod small endbush (axial)Distance between pistonpin seats (axial)

94-o.25-0.45

+0.400vc

0.25-0.8s

Assemblingthe piston

of

The distance between the top surface ofthe piston and the up{::r end surface of thecylinder liner with tie piston being atT D.C. as sh(l'vn in the fig

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PermissibleIOrerance0.5mm betweencylinders in therange of 9.7

+ 1 .50

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DESIGNATIONOF ASSEMBLY

POStTloNsORMATCHED PARTS

OIMENSIONSOFNEW PARTS


PERMISSIBLE

CLEARANCE

WEAR

LIMIT

Cylinder head

ValvesDiameter for valve spindJeguides

-oitQ22 -oE

a22Ec''0 .10 -0 .14 0.40

Outer-diameter of valvespindle guidesHoles for fitting valvespindle guides in cylinderheads

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DESIGNATIONOFASSEMBLY

POSITIONSORMATCHED PARTS

DIMENSIONSOFNEW PARTS

CLEARACEIN NEW

ASSEMBLY

PERMISSIBLE

CLEARANCE

WEAR

LIMIT

Valve tappet

Roller pin

Tappet pin hole

oO30 -oc:4

{OCl2O30 -o@

0.007-

(interference)o.o2(clearancel

Valve rocker arm

Shaft of Inlet valverocker armBearing of Inlet valverocker arm

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DESIGNATIONOFASSEMBLY

POSITIONSORMATCHED PARTS

DIMENSIONSOFNEW PARTS

CLEARACEIN NEW

ASSEMBLPERMISSIBLE

CLEARANCE

WEAR

LIMIT

Fuel delivery

pump

Pump bodyPump gear - -- -{OCg@3/ / . 5 o

oO37.34-o

0.10-0. '13

(at one side )0.25

Pump-shaftShaft bush

-o(2o20 -.oG

@20(zr0.025-0.04 0 . 1 5

Axial clearance ofpump gear o.08-o.12 0.20

Cooling waterpump

Front end coverWater-seal ring o14o E

-ct't 5O140 -oG

0.115-0.226 0.8

Pump casing

Water-seal ring

-o?@90 -o*

ago 2E0.165-0 345 0.5

Camshaft

driving

Intermediate gealbushIntermediate gearseat

{('tt@180 {o'ls

-C'(EQ180 -oe

0 .12"0 .18 0.3

Axial clearanceof the intermediateqear 0.20-0.35

0.6

Backlash of thecamshaft gear

Module ofGears = 5

0.26-0.34 0.45

Driving for threepumps

Running clearancebetween pumpdriving gears at thefront end of theenorne

Module of

Gears = 40.20-0.30

Driving forGovernor

Running clearancabetween bevelgearsRunning clearancebetween cylindricalqears

Module ofGears =3Module ofGears = 5

0.12-0.24

0.15-0,22

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OUTLINE OF MODEL 8320 MARINE DIESEL ENGINES

CHAPTER 2


The model 8320 Marine Diesel Engine is an irreversible model of 320 series of products.The engine is rigid in structure, safe and reliable in operation, durable in service, excellent incontrol performance , easy to maintain and good in economy.The marine main engine can be equipped with the remote control device so as to improvethe operating performance of the ship and the labor condition in the engine room for theoperator .The diesel engine has four strokes which are composed of suction, compression, working,exhaust. The diesel engine continues working in such circulating.The diesel engine may be made different type according to the different working condition inorder that the user may choose the suitable engine-1. The diesel engine is irreversible. lt may drive either fixed-pitch or conlrollable-pitchpropellers through the gear box and is used as main engines for freighter, passenger andworking ships for special purpose.2. The diesel engine is used as the power for the mud pump equipped with mud drag.The structure features of the model 8320 Marine diesel engine are as follows:The engine block and bedplate are made out of cast iron with a thick wall and are fastenedtogether by means of two-line tension bolts as a strong rigid body.The crankshaft is made out of nodular graphite cast iron with the large journal (model8320ZCd-8 diesel engine is Electroslag smelting casting steel crankshaft). Two cranks ofevery cylinder are provided with balance weights so as to ensure good dynamic balanceand good working conditions for the main bearings. The crankshafi is up to the requirementsof shipbui lding at home and abroad.The nodular graphite cast iron piston is "suspended type". lt has some merits, such as lightweight and high strength of structure, and small vibration when the engine operating. Thepiston is made with a cooling chamber in ib upper part and cooled with lube oil. Theconnecting rod body is columniform. The split face of the connecting rod is bevel cut typewith serration for positioning. The piston pin is the floating type.The cylinder head is made of vermicular cast iron and provided with two inlet ports and twoexhaust ports. The valve seat ring is made of heat resisting steel and the valve surface iscoated with a layer of heat-resisting hard alloy, so the valve seats is long life in service. Theexhaust valves of HFO engine is made out of NiMoNiC.All the cams are fitted on the cailtshaft with interference without keys . The cam angle can

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be hydraulically adjusted. The camshafi can be mounted and dismounted transversally soas to reduce the mounting and dismounting space in the engine room.The MIXPC turbocharging system is adopted in the engine with a turbocharger of excellentperformance and a high efficiency air cooler The inlet and exhaust manifolds are installed inthe same side of the engine in order to be easy to operate.The valve mechanism such as push rod, rocker arm is completely enclosed to reducemechanical noise .The engine is equipped with a variable-speed hydraulic governor so it has an excellentspeed governing performance. Furthermore, the engine is equipped with an over-speedlimiter with safety function, nameiy, the engine is stopped due to over-speed.The lube oil pump, cooling waler pump, fuel delivery pump and the tachometer generatoretc. are mounted at the front end of the engine and driven by the crankshaft.At the front end , the engine is provided with a damper to improve the torsional-vibrationcharacteristics according to the shafting.At the free end, the engine is provided with an extension shafi according to the requirementof the user, such the engine can take off the continuous power of 240kw at the raled speedof the engine. The Guangzhou diesel engine factory is not responsible for the fault engine,which is caused because the output shaft is not carried out the torsional-vibrationcalculation by user.The marine main engine is provided with the remote control device and is very easy to bethe local operation and remote coirtrol operation changeover.The engine is equipped with alrto-alarm device for lube oil pressure and temperature, forcooling water temperature etc., and instrumentation for monitoring the diesel parametersThe lube oil coolet fresh water cooler and lube oil filter are mounted outside the enoine.

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ENGINE MAIN COMPONENTS

CHAPTER 3 ENGINE MAIN COMPONENTS

3.1 Main Moving PartsModel 8320 Marine diesel engine may fit the nodular graphite cast iron crankshaft orelectroslag smelting casting steel crankshaft according to the strength.

3.1.1 . Nodular graphite cast iron crankshaft

Fig. 3-1 Nodular graphite cast iron Crankshaftl.flywheel bolt 2. flywheel 3. Hex-socket cap head screw 4. oil throw ring5. timing gear 6. bolt 7. crankshaft 8. vibration damper L resilient gear assembly10. oi l leading shaft 11. gasket r ing. 12. gasket 13. connecting bolt 14.bolt

The crankshaft (7) is made of high strength nodular graphite cast iron with excellentperformance. lt has rational design in crank webs and journals, so that the stresses duringoperation are evenly distributed in its different parts, resulting in sufficient strength. lt is wellbalanced, and the main bearings are running in excellent conditions, as counter-weightsbeing casted onto each crank web to reduce the unbalanced centrifugal force and internalmoments. Both diameters of the main journal and crank-pin are 250 mm. There is aconcave profile fillet between the journal and the web, which provides a larger fillet radius

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without shortening the effective length of the bearing, and reduces the stress concentrationin this part. There are two slope oil passages keeping away from the internal hole of journal,to connect with crank web pin. The take-off flange of the crankshaft and flywheel (2) aresecured together by ten bolts (1) (dia.32) fitted into reamed holes (dia.32mm). The timinggear (5) on the crankshafi is bolted to the crankshaft flange with bolt (6). There is an oilthrow ring (4) fitted on the take-off end of the crankshaft, the ring is made up by two boltshalves. The tightness of the bolts should be checked when reassembling, so as to avoid anydamage resulting from bolt loosening.3.1.2. Electroslag smelting casting steel crankshaft

Fig. 3-2 Electroslag smelting casting steel crankshaftl.flywheel bolt 2. shaft for sealing oil 3.fly wheel 4. hex-socket cap head screw5. oil throw ring 6,timing gear7. bolt 8. crankshaft 9. counterbalance 10. parallelpin 11. bolt for counterbalance 12. hex-bolt 13. Twin-wing lock washer 14. checkwasher 15. plug screw 16. vibration dampar 17. elistic gear assembly. 18passed-oil shaft 19. gasket ring 20. gasket 21. connecting bolt 22. bolt

The crankshaff (8) is made of electroslag smelting casting steel with excellent performanceand high fatigue strength. lt has rational design in crank webs and journals, so that thestresses during operation are evenly distributed in its different parts, resulting in sufiicientstrength and rigidity. lt is well balanced, and the main bearings are running in excellentconditions, as counter-weights (9) being casted onto each crank web to reduce the

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unbalanced centrifugal force and internal moments. Both diameters of the main journal andcrank-pin are 250 mm. There is a concave profile fillet between the journal and the web,which provides a larger fillet radius without shortening the effective length of the bearing,and reduces the stress concentration in this part. The take-off flange of the crankshafi andthe flywheel (3) are secured together by ten bolts (1) (dia.32 mm) .The five bolts thereof arefitted into reamed holes. The timing gear (6) on the crankshaft is bolted to the crankshaftflange with bolt (7). The oil hole ot the crankweb coats "letai242" and is blocked with plugscrew There is an oil throw ring (5) fitted on the take-off end of the crankshaft, the ring ismade up by two bolted halves. The tightness of the bolts should be checked whenreassembling, so as to avoid any damage resulting from bolt loosening.Installation of crankshaft counterbalance

Fig. 3-3 lnstruction diagram for the 60' angle between the mark lines of thebolt and counterbalance when the bolts of counterbalance are tightened.

a. Clean all contact surfaces, coat threaded portion with thin anti-friction material laver ofMoSz.

b. Check the thread and body of counterbalance bolt which can not contact with bolt hole ofcounterbalance.

c. Method of tightening the counterbalance bolts : tighten diagonally the bolts ofcounterbalance rn 3 sfeps to a torque of 550 N.m by means of a torque spanner, thendraw the two mark lines on the bolt head and counterbalance separately , angle of the twomark line is 60" ,finally turn the bolt of counterbalance to 60,at the same time, the twomark lines align

d. The bolts should not move when the bolt is tightened by 800 N.m after the bolt istightened

e. Drill two holes in the hole position of check washer (the hole is not near the edge), the

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depth of the drilling hole is 23mm, the depth of the tapping hole is 20mm. the diameter of thetapping hole is 11mm. then add the duplex stop washer and tighten the bolts, finally Lockthe two bolts with duplex stop washer.There are scale marks on the circumferential surface of the flywheel indicating TDC andsome adjacent crank angles for each cylinder. The crank position of individual cylinder canthus be determined when checking the valve and/or injection timing, via the pointer fixed onthe rear cover. Notches for turning the engine are also casted on central part of the flywheelperiphery.The passed-oil shaft is mounted when the crankshaft is equipped with the Gazling coupling .The shafi for sealing oil is mounted on the take-off end of the crankshaft in order to seal theoil inlet and outlet holes when the crankshaft is equipped with highly elastic coupling.The Gazling coupling is tightening on the flywheel by 24 bolts of M20. The passed oil shaffis bolted to the flange of the take-off end of the crankshaft. The lube oil passes through thepassed oil shaft to Gazling coupiang which produces damp, reduces the torsion-vibration ofshafting and lubricates and coois the Gazling coupling.The installation requirement of the Gazling coupling1) Adjust the distance between end surface of passed-oil shaft and end surface of flylvheel

F + 0 1 5

to 5.oro with shim, adjust the gap between end surface of passed-oil shaft and sealsurface of Gazl ing coupling to 6 =9.1-9. ' tUmm with shim, this device should not leak oi lduring working.

2) When the Gazling coupling aligns, the end face run-out is not more than 0.01mm in therange of every 100mm diameter, diameter runout is not more than 0.08mm.On the crankshaft free end, the elastic gear as illustrated in Fig. 34 is mounted. All thepumps for oil, water and fuel for the engine are driven by crankshaft.

The hub (3) and thrust plate (1) of the gear are secured onto the end face of the crankshaft(5) by bolts, There is a spacer (4) between crankshaft and hub. The tooth ring (2) is freelysupported on hub (3) with an axial clearance of 0.2-0.4mm, and a radial clearance of0.07-0.'175mm.The teeth ring is driven via spring holder (10), spring (11) and (12). Thespring holder (10) is laterally positioned among the hub, the tooth ring and thrust plate. Thesame buffer effect of the spring set can be realized in either direction, the dynamicfluctuating load of the driving gears can thus be reduced. Gears meshing to the resilientgear are: driving gears for lube oil pump (7), for water pumps (6) (8) and for fuel oil deliverypump (13) and for tachometer probe (9).During reassembling of the resitient gear in case of dismounting, it should be noted that thatall slop washers should be replaoed and all screws locked.

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ENGll t i : : MAIN COMPONENTS

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Fig. 3-4 The resilient gear

1. thrust plate 2. tooth ring 3. hub 4. spacer 5. crankshaft 6.driving gear forthe water pump T.driving gear for oil pump 8. driving gear for the water pump 9.driving gear for tachometer motor lO.spring seat 11. ouFide spring 12. innerspring 1 3. the driving gear for the fuel delivery pump

On request, an overhanging front take-off shaff may be connected with the free end ofcrankshaft , which may drive other auxiliary machineries. The take-off power is less than240kw.lf a front take-off shaft is provided (see Fig 3-1), the spacer will be removed and the flangeof the take-off shaft will replace a spacer, at the same time, there are reamed screwsbetween the take-off shafi and the crankshaft so as to ensure take-off torque transmission.

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A silicone oil damper is installed at crankshaft free end in order to improve the torsionalvibration characteristics of the shafting ,the propeller ,the diesel engine and whole system.Referring to the crankshaft drawing. The leaf-spring damper or spring coiling damper maybe installed in order to reduce thtl torsional stress of diesel engine crankshaft.When the crankshaft installs the leaf-spring damper or spring coiling damper,the O-sealring is installed, remove the tightening screw with groove.

Method of Measuring the Grank-web DeflectionThe crankshaft should be placed evenly on all main bearings. As deformation of the centralpart of the crankshaff should be resulted by itself weight when placing only on two endbearings. Crankshaft deformation could not be Cemonstrated if only the conlact areabetween the journal and the bearing was checks. During engine operation, the crankshafr issubject to repeated periodic bending in the case of improper assembling or uneven wear ofthe lower hatves of main bearings, Fatigue damage, cracking or even rupture of crankshaftmaterial will naturally be the result of numerous such repeated deformation.The distance between two crank'webs of the same crank is known as crank web distance,The difference between the nreasured maximum and minimum values of this distanceduring one revolution of the cran L, L< t '

Fig. 3- 5 Elastic Oeflection of Crankshaft

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The crank-web distance L at T.U.C is larger than that L'at B.D.C., i.e. L > L', if the position oftwo main bearings of the crank in question is lower than their adjacent main bearings. Theaxial line of the crankshaft is in the down-warp shape, the value of crank web deflection inthis case is assumed to be (+) .On the contrary, if the position of two main bearings of the crank in question is higher thantheir adjacent main bearings, so that L

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horizontal lefr and right, in other words, at four crank angles: 00, 900,1800and 2700. Themeasurement can be carried out without dismounting the piston and connecting rod. Theshank of the connecting rod may knock against the neter when the crank pin is at B.D.C(1800). In this case, the job can be done by following the measuring sequence given in Fig.3-6, measured values are filled in Table 3.1 . The mean value of points 5 and 1 is taken as theresult measured at B.D.C. Attention should be paid to make sure of not knocking the meterby the connecting rod, otherwise ihe result may be wrong or even the meter damaged.

Table 3.1 Measured result of crank web deflection

Allowable crank-web defl ection1) Crankshaft is supported cn bearings without flywheel + 0.035 mm

2) The crankshaff is fitted with a standard flywheel, for that cylinderadjacent to the fly-wheel (cylinder No. 8): -0.10 mm

3) The crankshaff is elastically connected to the shaffing and the flywheel is mountedadditional weight such as elastic coupling or air tyre clutcher elc (corresponding toincreased weight of flywheel), the more permissible value of crank-web deflection is ,themore addition weight is permissible value of crank-web deflection - 0.13 mm

Cylinder No.

CrankshaftPosition

1 z 4 6 7 o

1 B.D.C(exhaust pipe side )

2 Exhaust pipe side3 T.D.C4 Operating side5 B.D.C

(operatinq side)Maximum crank- webdeflectionMeasured results should be filled in technical reference, with the date and load condirrons.

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limib for readiustrnent: -0 .15 mm

Maintenance of Crankshaftln addition to regular measurement of the crank-web deflection, attention should also bepaid to the following:1) Regular checking the quality of lubricating oil, preventing dust or foreign substances

from entering into the lube oil system so as to ensure good lubrication conditions forthe crankshafi .

2) For those bearing shells with working surface defects, inspect their matching journalsand reface carefully existed defects such as scratching or scoring etc. repair thebearing shells and then reassemble.

3) Attentively observe surfaces of the journals and webs, especially fillets and oil holesfor any possible cracks and/or damages, using a magnifoing glass with a factor of 3 to

4) Regular checking the wear extent, ovality and conicity of all journals. lf a reduction ofthe journal diameter of 0.20 mm (comparing to the standard values), or the ovality of0.10 mm or more being reached, such a crankshafi should be sent to the manufacturerfor regrinding. Crankshaff like this may also be repaired by means of filing, and thenpolished using finest abrasive cloth, special aftention must be paid to the oil holes andfillets. The radial runout ef journals and the parallelism of the main and crank pinjournals and crank-web deflection should be checked as well.

3.1.3 Piston and Connecting Rod Assembly3.1.3.1 PistonThe oil-cooled integral "suspended type" piston (1) is made of nodular graphite cast iron.The top of crown is machined to be "trr' shape, which makes up the combustion chambertogether with the cylinder head. Four recesses were cut on the crown to avoid the pistoncolliding with the valves.There is a threaded hole in the middle of piston top for lifting the piston .There are totallythree compression rings and one scraper ring in the piston crown, Lube oil passages areprovided in the scraping groove, which allows the scraped oil returning to the crankcase.In order tO reduce the temperature of the top surface and the ring-belt of the piston, there isa casted cooling chamber in the piston crown. Lube oil flows from main bearing via oil holesin the crankshaft and connectinu iod to the oil passage of the piston pin (11), and then viathe oil-groove in the piston pin seat and inlet oil hole, finally into cooling chamber. Aftercooling the piston crown, the tii flows through the screw plug (7) of piston back to thecrankcase.

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ENGINI: MAIN COMPONENTS

Fig.3 - 7 Piston arid Connecting Rod Assemblyl.piston 2.piston ring 3.piston ring 4.piston ring 5. scraper ring 6.plug screw 7.oiloutlet plug screw S.screw 9.circl ip 10.screw 11.piston pin 12.copper bushl3.connecting rod l4.locating pin bushing 15. lockwasher lG.connecting rod short bolt17. bolt 18. upper bearing sheM 9.bottom bearing shell 2O.connecting rod cap 21.longer connecting rod bolt

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The piston is made of nodular graphite cast iron ,which is "suspended type' ,thin wall andstrong back with high rigidity and light weight, it can bear higher temperature. Mechanicalload is passed to piston pin seat directly by the vertical reinforcement rib, at the same time,the side trust is passed by horizcntal reinforcement rib. This struciure has enough rigidityand strength to prevent the piston pin seat from deforming. The piston skirt is thin-wall, andcylindroid, to ensure reliability when the engine operates under the thermal state and heavyload. In this case, the piston is not easy to be scuffing of cylinder bore, the piston clearanceis small, the noise of the vibration is low and the load-carrying ability is big.3.1.3.2 Piston Ring

There are three compression rings fitted onto the ring grooves to seal the combustion gasesand ensure the heat transfer from the crown to cylinder liner and then to the cooling water.These rings are made of high strength alloy cast iron and their working surface ischrome-plated. Three compression rings is double cone shape, drum shape and coneshape according to the working condition .On the upper of the rings: sculpture "13E.02" forthe first compression, sculpture "138.03' for the second compression, sculpture "13E.07" forthe third compression. In order ii' ensure that the rings can display air seal, oil seal and oildistribution function, the sequence of ring can't be confused and the sculpturing end of ringsmust be upward .ln order to prevent air from leaking, the joint of different rings should bestaggered each other during assembling.To prevent lube oil from entering the combustion chamber, an oil scraper ring is fitted abovethe piston pin seat.However, no scraper ring is arranged in the piston skirt, so this area canbe sufficiently lubricated. The oil ring is spring expandef ring type, the radial pressure of theoil ring is big, so the performance of scraping oil is strong. The flexibility of the oil ring isgood, so the oil ring mates the wall of the cylinder evenly,the pressure of the oil ring to the wall of the cylinder is stability, the decreasing of theelasticity is small when the ring is worn, the consumption of the lube oil is small. There is aoil{hrough hole in the middle of tf 'e ring.3.1.3.3 Piston Pin

In cool condition, the fit clearance between the piston pin and piston pin seat is 0,048 to0.073 mm, and the fit clearance between the piston pin and the copper bush in theconnecting rod small end is 0.195 to 0.243 mm. For assembly, slightly push the piston pininto its seat- In operation, the piston pin can be rotated relatively to the connecting rod or tothe piston. Therefore, wear will be very uniform peripherally, and jamming can be avoided.To prevent piston pin from axial moving, a clip rings (9) are installed in grooves of seat. Thepiston pin (11) is a hol low cyl indrical, which is dri l led holes in longitudinal and radialdirections for the passage of lube oil, The pin end surface must be plugged by screw plugand caulked to the screw plug hole to avoid its looseness.3.1 .3.4 Connecting Rod

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The shank (13) and small end of the connecting rod are stepped type .The shank of theconnecting rod is a circular cross-section. The angle of the bevel cut to the shank is 40'withlocating by angular rack tooth rack. The shank and big end cap are connected together bytwo longer (21) and two shorter (1 7) connecting rod bolts of M 27x2 ,made of high qualityalloy steel. These bolts are locked by means of lock washer (15) and M8 x 12 bolt (17). Alocating pin bush (14) is pressed in the oil hole of the cap for axial location, which is hollow.The internal hole of the bush is the oil passage. The finish machining of the connecting rodbig end bearing hole is carried out as the cap and the shank is secured together. Acounterpart mark is made on the same side of the cap and the shank respectively. Thesemarks should be mated without mistakes when reassemblingThere is an oil groove with 5 mrn in depth and 14 mm in width in the inner surface of the cap(20), which is connected to the oil hole of shank via two angular holes of o 10 and a straighthole of o 16. There is also an oii groove in the small end bush that connected to the oil holeofthe shank. Lube oil coming from the oil hole ofthe crankshaft flows to the oil groove ofthelow half of the connecting rod bearing shell(19), to the oil hole of the shank and to the smallend and bush (12), then to the piston pin (11). On the top of the small end ofthe connectingrod, a plug screw is used to block the hole for maching the oil hole.The bush (12) is made of tin bronze and fitted to the hole of the small end with interferenceof 0.117 to 0.149 mm. There are oil grooves and holes in its inner surface to introduce lubeoil into the bearing surface and to the piston pin and then to the cooling chamber of thep is ton .There are bearing shells with coated tri-metal alloy laye(8320cd4 is bearing shells of hightin aluminum alloy) and fitted in big end bearing holes, a location pin in the bearing shellinserts to the recess of the connecting rod.Maintenance of the PistonOne of the piston should be dismounted for inspection after every 3,000 operating hours,Observation of surface conditions of all cylinder liners from the inspection window incrankcase box should be carried out. The piston in such a cylinder where heaviest wear isfound should be chosen to be withdrawn. lf no serious scratches or wear of the cylinder linerworking surface found, the conditions of ihe withdrawn piston being normal, all rings beingwell movable without heavy wear, inspection of all other pistons in this case may be put off.However, all rings and pistons should be inspected with the operating hours not more than8000.lf abnormal condition of the dismounted piston and piston rings found, other pistons should

then be dismounted for inspeciion.Diameters of the piston and the cylinder liner should be measured at the same time. Theliner should be replaced if the tolerance clearance reaches the limit values specified inchapterl.lf the wear extent of the pin hole has reached the limit given in chapterl , the piston

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should be replaced as well.When any piston ring sticks to its piston ring groove with carbon deposit(this will cause poorcombustion resulting from reduced compression pressure). use gasoline or carbontetrachloride to wash off the carbon deposit, the ring is then knocked down using a woodmallet and then dismounted. lf the tolerance clearance reaches the limit values specified inchapterl as the ring worn out, oi ring spallation is found, the ring should then be replaced.lf cracks are detected or the tolerance clearance reaches the limit values specified inchaperl as seriously wore out, the piston pin should be replaced.Afier maintenance of pistons, cylinder liners and piston rings, the engine should be runaccordinq to the following table, the diesel engine ma after runnmodel 8320ZCd4 8320ZCd-6 832oZCd-8Speed(r/min)200 315 J Y / 454 210 aan 417 477 210 330 417 477Time (min) 30 30 120 120 30 30 120 120 30 30 120 120

Replacing of Piston Ring

Fig. 3-8 Assembling and Dismounting of Piston RingThe gap of the joint should be checked when assembling a new piston ring. Firstly , the ringis put into the corresponding cylinder liner with its top end parallel with the liner end face,and the gap measured by means of a feeler should not exceed values specified inchapterl.Secondly,the ring is put into the groove, and the side clearance is also measuredby means of a feeler, which should fulfill requirement given in Chapterl . The joint of eachring should stagger each other for 120'.Two rings (3) as illustrated in Fig 3-8 may be madeby the user and then hitched up lhe ring joint as shown in Fig 3-8 to pull open the ring. lt is

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essential not to pull too much to prevent the ring from being broken.Maintenance of Connecting Rod

1. The connecting rod bolt is such an imporlant component that its fracture will result inserious damage of the engine. After every 100 operating hours, the pretighteningcondition of each bolt should be checked by way of lightly knocking bolt heads. All fourbolts should be retightened if one of them being loosened,The pretightening condition of connecting rod bolts should be checked as follows afterfirst 250 to 300 operating hours in case of a new engine or the crank pin bearingsbeing reassembled

1) Remove the small bolts and lock washers on the connecting rod bolts.2) Mark the relative position between the connecting bolt head and connecting rod.3) Try to retighten the bolt by a torque spanner with a torque of 800 Nm. lf the marked

position of one of the four bolts has been changed, all of the four bolts should beretightened and then reassembled with new check washers.

The connecting rod bolts must be replaced if any of the followings should happen1) Crack(s) is found on the connecting rod boli;2) The engine is shut-down as the piston seized up in cylinder liner.3) Accumulated operation time is over 20000 hours.No defects should be found on threaded part of the connecting rod bolt, defects such asscuffing etc. on the shank of the' connecting rod should be polished off, special attentionshould be paid to the fillet area.2. lf the clearance of the small end bush has exceed 0.4 mm, the bush should be

replaced.3. Should defects of the connecting rod such as cracks, twisting or deformation were

detected, the connecting rod should be replaced4. The connecting rod should be checked for deformaiion and cracking in case the piston

was seized up in the cylinder liner or the ship was stranded resulting deformation ofthe crankshaft and bedplate. Measurement method is shown in 3-9. Differencebetween L and L'is not allowed to exceed 0.12 mm ,while that between H'and H notto exceed 0.2 mm.

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Fig.3 - 9 Measurement of the Connecting RodThe Dismounting ot Piston and Connecting Rod1. Drain al l cool ing water in the engine block.2. Dismount the cyl inder head.3. Open the test valves of the cylinders.4. Turn the piston to its B.D.C, clean off the carbon deposit in the cylinder liner. Check if a

step had been formed in the position of the cylinder liner in the position corresponding tothe T.D.C of the first piston ring. In case that yes, the step should be smoothed with anoilstone and then cleaned. Then coat grease on the cylinder liner surface so that whenthe piston is drawn out, the residual carbon particles or metal particles can be buried inthe grease and will not scratch the cylinder liner.

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5. Install the tool No. 320.100.20A on the piston top, run a rope through it and hang ii upwith a liffing hook. Turn the crankshaft to the position for most convenient dismountingconnecting rod bolts. Strain the rope with a crane.

6. Loosen the bolts diagonally, first unscrew the two bolts for the mounting tool fordismounting connecting rod.

7. Install the tool No. 320.100.120A through the observation window, slide the two pins ofthe tool into the tapped holes of the dismounted bolts.

Fig. 3 - 10 Mounting and Dismounting of the Connecting RodRemove the other connecting rod bolts. Use the tool to take out the connecting rod cover.Remove the tool.While turning the crankshaft slowly towards the direction away from the connecting rodopening, lifi the piston up slowly until the crank-pin no longer interferes with theconnecting rod big end when the latter is lifted up from the cylinder liner. Remove theconnecting rod upper shell, tren carefully lift up the piston and connecling rod togetherfrom the cylinder, pay attentir.n to avoid the connecting rod scratching or bumping thecylinder liner.

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9.

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ENGINF MAIN COMPONENTS

10. Use a stand to support the piston and connecting rod so as to avoid the connecting rodtouching the g round.

11. Upon inspection, if the connecting rod is dismounted, first the circlip in the piston pin seatshould be removed.

12.Turn the piston and connecting rod assembly upside-down so that the piston top canface downward. Install the tool No. 320.100. 180 onto the piston pin and remove thepiston pin.

13. Clean and inspect al l partsAssembly the Piston and Connecting Roda. Measuring and recording dimensions of the piston pin and its hole as well as the

small end and checking if the results fulfill the requirements given in Chapter 1.

b. Lifting the connecting rod with the small end downward.c. Fit t ing the special tool No. 320.100.180 onto the piston pin.

d. Turning the piston upside-down with its top end laying on a wood-plate.e. Fit the small end into the piston while paying attention to the bevel cut towafd the

mark 'p' on the piston, namely, toward the exhaust valve.

f. Fit the piston pin into its holes in the piston and the connecting rod, and thendismount the special toal.

g. Fitting retainer ring to both ends of the piston pin hole.h. Turn the piston-connecting rod upside down and put them onto a support frame.

The above method is based on the case where the piston is placed stationary. lf conditionsare available, the work may be performed in such a way that the connecting rod is fixed withits small end pointing upwards, and then liff the piston up and slowly mount it onto theconnecting rod,Maintenance of Connecting Rod Bearing shellsThe wear condition ofthe big end bearing shell and small end bush should be checked afterevery 3000 working operaling hours.lf abnormal wear , spallation or r:racking was detecteci from the dismounted bearing shell orbushes, the others should also be dismounted for inspection, those bearing shells or busheswith defects impossible to be corrected should then be replaced.

It should be noted during replacing the small end bush, that the wider side must be closed tothe big end.Any scuffing on the journals of the crankpin should be removed by neans of grinding stoneand be polished by using the fine abrasive cloth.

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o .

d .


In the case of replacing the bearing shell , the shell should be fitted into the connecting rodas per the assembly requirements, and the bearing hole diarneter should be measured andrecorded as per requirements given in technical certificate, and then write down the date ofreplacernent.Parallelism and twisting of both the big end bearing and small end bush should be checkedafter replacement as shown in Fig 3-9-lf the requirements of clearance given in Chapter 1 are met, the assembly can then be fittedto the engineFitting of Piston and Connecting Rod

a. Clean up thoroughly the internal surfaces of cylinder liner and the crankpin, coat themwith clean lube oi l , and place the assembling tool No. 320.100.30 on top of the cyl inderl iner.

Lifl and clean the assembled piston-connecting rod assembly, check if cuts of pistonrings being staggered and apply some lube oil.Turn the crankpin close to the exhaust side.Carefully and slowly fit the assembly into the cylinder liner, The side of piston crown withthe mark 'p' must close to the side of exhaust pipe.

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e. Turn slowly the crankshafi unl;i that the crankpin enters the bearing in the big end of the

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ENGIl', iE MAIN COMPONENTS

connecting rod.f. Fit the tool No. 320. 100. 120A onto the observation window. Place the connectinq rod

cover with lower half of the bearing shell onto the tool, and fit it to the big end.g. Coat MoS2 on both the thread part of the connecting rod bolt and friction surface of

the hexagon head, diagonally install the connecting rod bolts, tighten them slightly with awrencn.

h. Dismount the tool No.320. 100" 120A , then fit the other two bolts.i. Turn the crankshaft to a position suitable for pretightening the bolts. Then pretighten the

bolts as followsa) Pretighten the bolts diagonally and alternatively in 3 tinres, the torque of long bolts

of connecting rod is 3101{.m, the torque of short bolts is 270N.m.b) Draw the base line in the hexagon head of bolts and connecting rod cap, Use a

torque wrench to turn the tour bolts in 3 to 4 times alternatively and diagonally to 60oegree

c) The bolts should not turn when the torque is 800 N.m for check.lf no torque wrench is available, the pretightening method is as follows:(a) With a wrench of 400 mm handle , pretighten the four connecting rod bolts by

one hand alternatively and diagonally.(b) Mark the base lines in hexagon head of bolts and connecting-rod cap connecting

rod cover, and Use a long wrench to turn the four bolts in 3 to 4 timesalternatively and diagonally to 60 degree .

The bolts should not turn when the torque is 800 N.m for check. Move the connectingrod with lever to check if the connecting rod can move axially on the journal.

j. Place lock washers and tighten lhe screws for the lock washer.k. Check the axial clearance ofthe connecting rod small end.l. In the case that the bronze bush of the connecting rod small end or the cylinder liner is

replaced, or the engine has operated for very long time, the following inspections shouldbe carried out before final installation is made. These inspections are to be made with thepiston without piston rings ano the assembly already is fitted into the engine as per theabove procedures.

Use a feeler gauge to measure the clearances at four positions of the lower end of pistonskirt in crankshafi axis direct ion to rneasure i .e. a'and b'at T.D.C and a and b at B.D.C, asshown in Fig. 3 -9, Maximum difference of them should not exceed 0.10 mm. otherwise thecause should be found out. The parallelism of big end and small end of the connecting rod

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should be checked according to Fig.3-g .lf necessary, the bronze bush of the small end maybe scrapped by a skilled worker. After scraping, smear test with the piston pin should thenbe done to ensure even distribution of the contact spots. The su rface rouohness Ra shouldbe not more than 0.4 um.lf all these have been done, reassemble the assembly into the cylinder liner. lf being up tothe standard, the assembly is dismounted to fit piston rings and finally fitted into the engine.m. Check the distance 6 between top of the piston and top end of the liner when the piston

being at T.D.C as shown in Fig 3-13,if the piston or cylinder liner had been replaced. Thedifference of 6 for different cylinders in the same engine should not exceed 0.5 mm.

Fig. 3 - 12 Positions for Clearance Measurement of the Piston

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ENGINF- MAIN COMPONENTS

Fig. 3 - 13 Checking of Distance,6Between top of the piston and top end of the liner

tnspection and evaluation of tri-metal bearing shells of connecting rod (suitable forModel B320ZCd-6, 8320ZCd-B diesel engine).Note: The criteria mentioned below are used for the assessment of tri-metal corrosionresistent bearing shells consisting of a lead bronze-lined steel back with a nickel dam and aplated overlay of 0.015-0.035.11 is recommended to open perfectly running bearings asseldom as possible because they have to adapt themselves again after every assembly-

The big-end bearings of the connecting rod are equipped with a corrosion resistent tri-metalbearing shel l .Contaminated oil, solid foreign matter and water are the cause of 85% of all cases ofbearing damage. Dirt is the enemy to all bearings. A thorough oil treatment and a carefulfilter maintenance are therefore indispensable for a reliable operation and a long life.

The plated overlay has much better running-in and continuous running properties than theharder lead bronze. In addition, lournal and crankpin wear is greatly reduced by the platedoverlay.lf the plated overlay is corroded by heavy fuel operation or the engine is frequently startedand stopped (max friction), the bearings may be more rapidly worn so that they rnust berenewed sooner.Griteria catalogue (see illushation 3-14)1. Uniform dull grey surface

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The bearing function perfectly. A uniform running pattern can be seen in the mainload-carrying area.

2. Glossy area along the two edges of the bearingThe bearing is overloaded along the two edges. A slight gloss will disappear after a fairlylong time of operation. lf the gloss is very intense, the hard high spots should be touchedup with a scraper to ease running-in. Do not use emery cloth! lf the crankshaft has beenreground check the fillet radius between the web and journal or crankpin.

3. Heavy pressure on one bearing edge with lead bronze exposed over a large area:This is not permissible and the bearing must be renewed .lf such a wear pattern canalready be seen after a short period of operation ,it is of vital importance to find the cause,check the crank web deflection values.

4. Scratches in the plated overlay and lead bronze:The scratches are caused by dirt or foreign matter in the lubricating oil. lf such scratchesare not concentrated or do not reach far into the bronze they will be harmless. lf there area lot of scratches, the shells siiould renewed.

5. Plated overlay worn over a large area (bronze exposed)lf the bearing has been in operation for a long time and its surface and transition area atthe edges are smooth, there will be no danger. Check the shaft for wear. lf such wearpattern can already be seen after a shod period of operation, lack of oil supply could bethe cause. Check the journal or crank pin surface for increased roughness orscores. .Polish if necessary. lf the bearings of the connecting-rod are concerned, checkthe crank web deflection. Realign the engine if necessary. Renew the shells as aprecaution.

6. Renew the bearing if plated overlay is worn over a large area, bronze and nickel dam areexposed, deep score mark both in the plated overlay and bronze layer, Check the surfacecondition of the journal and crank pin and smooth it if necessary. Check the oil filter andpiping between the filter and engine. lf further bearings are fed with oil from this bearing,these must be inspected, too. Ensure extreme cleanliness during assembly.

7. Heavy pressure below the relief area near the parting line.These areas are sometimes marked by heavy pressure. Glossy area should be touchedup with steel wool or a scraper. Check the expansion of the free bearing shells. lf thereare small cracks with some scaling of lhe plated overlay, the shells must be renewed.

8. Cracks in the plated overlayMinor cracks are harmless. The bearings can be fitted again unless a very markedaccumulation of cracks exists r;., the loaded area and the plated overlay 3cales off.

3-22

ENGITIE MAIN COMPONENTS

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Fig.3-14 Criteria catalogue for bearing shell of connecting rod

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9. Depressions caused by erosion or cavitationThese depressions are generally sickle or kidney-shaped. They are recognized by thestepped edges of the damaged areas. The borderline itself is very irregular and, generally,small area with depressions exist next to the borderline. These depressions are harmless-However, if they are accompanied by damage in the lead bronze layer or if bronzeparticles are scattered and embedded over the bearing surface like freckles, the bearingmust be renewed and lhe Guangzhou Diesel Engine Factory representative notified.

10. Diagonal areas of heavy pressure:Make sure that the shells and bearing cap are fitted accurately. Measure the crank webdeflection. lf the plated overlay contains cracks and scaling, renew the shells.

11. The plated overlay is very smeary, the lead bronze is partly exposed(mainly along thetransverse centre line)(11a: inner surface,l l b:outer surface ofthe bearing):Galling due to lack of oil. Very often the outer surface of the bearing is quite black withcarbon deposits along the transverse center line. The bearing shells have contracted asa result of overheating (negative expansion). Check the bearing housing and journal orcrankpin for cracks. The sheiis must be renewed and it is essential to trace the cause.

12.Heavy working traces on the outer surface of the bearing and some areas of frettingcorroston:

Cause: insufficient prestress of bolts ,faulty assembly.The bearing must be exchanged paying particular attention to the assembly instructionfor tightening the bearing bolts. Check the crush of the bearing and inspect furthercrankpin.

1 3.Working traces on the joint faces of the bearing shells:Check the prestress of the bearing shells. Follow the instructions for tightening thebearing bolts exactly. Check the crush. lf such working traces occur on several bearings,notify the Duangzhou Diese! fngine Factory representiative.

14. Working traces on the joint faces (parting line) of the bearing cap and bearing housing(not available as figure).

Exactly observe the instructions for the assembly, especially those for tightening thebearing bolts. Try and smooth any roughness on the joint faces. lf the working traces areheavy notify the Duangzhou Diesel Engine Factory representative.Inspection and Evaluate of the bearing shells of the connecting-rod

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Note:The figures (from 3-1 5 to 3-1 8) show the wear pattern found in heavy fuel operation.Bearing shells with a corrosion resistant galvanized zinc layer is hardly affected in the eventof corrosion, which leads to considerably better running pattern. The mechanical wear isdominant here.Fig 3-15 Perfect bearing shell corresponding to Fig.1 on 3-1 5. Good uniform running pattern,hardty any wear, minor scratches and corrosion in the plated overlay. Proper lubricating oiltreatment. The shells can be used again-Fig 3-16 Typical wear pattern with transition areas afier a long period of heavy fuel oiloperation.

Area I -Plated overlay compietely conserved near the parting line. Protective tin flashstill existing.

Area II --Plated overlay still existing, but darkened and roughened by corrosion.Arealll--Transition area to the running surface proper. Narrow, almost black rim with

plated overlay heavily damaged by corrosion.Area IV --Plated overlay almost completely removed by corrosion and, partly, by

abrasion. Silvery bright nickel dam exposed.AreaV --Nickel dam worn away, bronze becoming visible.Area\4--Bronze becoming visible through minor scratches from dirt.

Fig3-17118 Various wear stiages caused by corrosion and abrasion of the plated overlay inheavy fuel operatio:r.

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Reassembly

A---- Minor conosion of the plated overlay. A narrow ship of nickel dam is exposedon one side. The shel l can be used again.

B---- Heavier corrosion of the plated overlay. Nickel dam exposed on both sides.The shell has nearly reached the wear limit. A perfect adaptation is no longerfully ensured. The hearing can operate another 50% of the time reached.

C---- A large area of the plated overlay has been removed by corrosion as far as thenickel dam. The running pattern is otheruise good. Although the bronzelayer has not yet been exposed, the bearing must be renewed because itcan no longer embed and adapt itself.

D--- Heavy corrosion of the plated overlay. Lubricating oil contaminated bySolid foreign matter causing additional n'lechanical wear of the platedoverlay with scraiches down into the bronze. Check the journal or crankpinfor scratches and smooth it with an oil stone if necessary. This bearingcondition is a considerable risk for the engine. Inspect further bearings,

E---- Heavy corrosion :nd abrasion of the plated overlay. Lubricating oilcontaminated by solid foreign matter causing additional mechanical wear ofthe plated overlay with scratches down into the bronze. Check the journal orcrank pin for scratched and smooth it with an oil stone if necessary. Thisbearing condition is a considerable risk for the engine. Inspect furtherbearings.

F-:- Plated overlay almost completely removed by corrosion and mechanical wear.The running pattern shows partial scoring by a lot of dirt in the danger ofheavy consequential damage. Check the journal or crank pin for scratchesand try to smooth it with an oil stone. Inspect all the other bearingsimmediately Clean the lubricating oil circuit. Inspect the filters andlubricating oil separators.

Replacement

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3-27

ENGiI*E MAIN COMPONENTS

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3.2 Main stationary Parts3.2.1 Cylinder block, Bedplate and Main Bearing

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Fig. 3 19 Engine Block and Bed-plate

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@ENGINi l MAIN COMPONENTSThe cylinder block (3) is made of high strength cast iron with comparatively thick wall. ltsconstruction ensures sufficient longitudinal and lateral rigidity. There are 8 cylinder headbolts (2) around each cylinder bore, a closed crank case is formed afier the cylinder blocksecured to the bedplate (13),to both ends of which front and rear end plates arefitted .Projection for assembling lube oil pump, fuel pump and speed transducer are castedin the front end plate, while those for driving gears of speed governor and over-speed limiteretc. are casted in rear end olate.In the horizontal platform of the operation side of the cylinder block, for each cylinder thereis a projection for supporting the tappets and three through-holes for placing the tappetsupports. The recess around the projection forms the oil return groove, from where the oilcould flow down to the return tube via a through hole.A long opening with the same length as the cylinder block on the side plan of the camshaftspace allows laterally dismounting the camshaft. Camshaft bearing seats with Y{ype openare casted in vertical walls of the opening. This long opening is covered by three longcovers (28), one small cover and a gear casing. Behind the interface of two covers, abase-plate (29) is added, soft wood gasket (30) are fitted with special arrangement forinclined lap-jointed so as to ensure the sealing ofthe cover interface. lt should be noted thatduring assembling, no gap of the gasket is allowed in the interfacing area. Movable pedal(25) for the operator to stand on for inspecting cylinder heads are mounted below thecamshaft covel which can be put down when not used in order to gain more space besidethe engine.The wet cylinder liners (27) are fiited in the cylinder block. There is an intermediate supportin the water jacket area, which is also functioned as the upper locating surface. There arealso 3 rubber "O" rings in the bottom locating surface (26), thus ensuring both the cylinderliner free expansion and water-tightness. This design reduces the distance betweensupporting points and the amplitude of high frequency vibration, increases the rigidity ofbearing the side force from the piston and the ability against cavitation.Inspection doors are provided in lower parts ot both sides of the cylinder block, forinspecting the conditions inside the crank case and assembling or disassembling mainbearings and connecting rod bearings. The windows in the front side are covered by covers(24) which are sealed with asbestos-packing gaskets. The 6 observation covers (8) on theexhaust side are equipped with explosion proof door (10) which will open quickly in case theoil mist in the crankcase is ignitc , so as to ensure that engine is safety.In order to decrease the presstiie in the crankcase which is formed due to the exoansion ofthe oil mist, two vent covers are provided in the exhaust side of the cylinder block closed tothe end surface, so the user is easy to install the breath pipe of the crankcase and leadoil-mist to the safe location of the deck.A cooling water inlet is provided for each cylinder on the exhaust side and the inlet is sealedby the cover (5) . The lower part of cooling water chamber formed by the cylinder block and

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the cylinder liner is wider than the upper part, this allows the water to flow upward evenly. Inthe intermediate support there are two notches perpendicular to the water inlet to changedirection of cooling water thus to enable cooling water sweeping the whole upper surface ofthe cylinder liner before it enters cylinder head via pipes (31) on either side.The engine block and engine bed-plate are tightened together mainly by 18 tie bolts (14) ofM 39 x 3, to bear the major part of the tensile force applied by combustion gases inside thecylinder. In addition to these tie-bolts, there are also 52 screws (12) ol M22X2 evenlydistributed in the joint plane. A sturdy rigid structure is formed after secured all bolts andscrews of the cylinder block and bed-plate. The tie-bolb are tightened in the crankcase bymeans of hydraulic tension devices 320.102.00A, The devices are screwed to the extensionparts of one pair of tie-bolts when tightening, the oil pipes 320.102.10 and 320.102.20 arethen connected. As the oil pressure is increased by a oil pump (320.103A.00) to 81Mpa, thedevices can be dismounted affer the round nuts in the long grooves of the pressure ringshad been screwed up. In the case of dismounting these tie bolts ,the only thing needs to dois to screw off the round nuts afier the oil pressure of the connected hydraulic tensiondevices had been increased to a liftle bit higher than 81Mpa. The sequence for tightening tiebolts is indicated in the figure beiow.

Fig. 3-20 Tightening of the Tie Bolts

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It should be noted that these scriws must not be over-tightening as the screw threads beingdirectly threaded in the bedFiate. The torque should be controlled in the range of216-260N.m to prevent the thread from damage. There are also four dowel pin (22), whichmust be fitted before tightening tie bolts and screws.on the output end ofthe engine, there is a bracket for turbocharger and the supercharging

air cooler and the air outlet cover for the supercharging air cooler.The integral bed-plate is made of cast iron. The joint surface of the cylinder block andbedplate is at 10 mm upward from the center line of the crankshaft.The rigidity and damping performance of the casted bedplate are comparatively good, themain bearing seats with sufficient thickness are devised on the lateral walls withreinforcement, which result in small deformation of the main bearings during engineoperation, so as to ensure the working reliability.In order to reduce the length of the cantilever part of the crankshaft. an 1Orh main bearing isprovided between the crankshafi driving gear and the flywheel. In other words, there aretotally ten main bearings, among which the gt one being the thrust bearing.The cap of main bearing (23) are made of cast iron ,and shrunkly fitted to the main bearingseat. The joint face of the main bearing cover and the bed-plate is at 10 mm downward fromthe central line of the crankshaft. Each main bearing is tightened by two main bearing boltsof M30 x 2 ('11) ln the inner surface of the main bearing cover, oil grooves and bearing shelllocating grooves are provided on the inner surface, there is an oil hole and tap hole on thetop surface for oil pipe connection.

The main bearing shells are oi aluminum alloy tin steel backing type, as illustrated in3-21 ,and are divided into upper shell (3) and the lower shell (4), The thickness of the ailoylayer is 0.8 + 0.1 mm. Oil groove is provided on the working surface of upper shell ,towhich 14 drillings of + 14 are connected. Lube oil from the crankshaft oil hole lows viathese drillings to the oil passage of the connecting rod, then to the cooling space of thepiston. Dowel pin (6) in the shell are matched to conesponding recesses in the bearing capand seat respectively to prevent the shells from rotating axially and peripherally. The jointface of bearing shells is 10 mm higher than that of the bearing cap, which allows the upperand lower shells to be fitted in the same cylindrical hole. Since the actual joint face beinghigher than theoretical one, adequate shrink range can thus be realized after bearingassembling.

On the bottom shell of the 9tn ma'r1 bearing, one thrust pieces (5) of tin bronze is installed oneither side for axial locating of tilr crankshaft. The spiii face of thrust collar is lightly pressesby the bearing covers to prevent them from rotating.

lf the engine is equipped with a lube oil suction pump, a suction pipe (1 7) wilt be arranged inthe lower part of the bed-plate so as to draw out the lube oil from io the bed-plate. In case

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that no suction pump is mounted, no suction pipe is provided and the lube oil will flow fromthe hole of the end face of the bedplate to the oil tank under the engine.

There are 30 holes of 627 drilled and 4 reamed holes of 0 25 on the four corner in supponsin both sides of engine bed-plate, which can be used together with the engine foundation forreaming the holes of anchor bolts. There are 6 tap holes of M 36 x 1.5 in the supports foralignment of the engine with the shaft system The adjusting bolts are screwed into theseholes to prop against the foundaiion for adjustment of the engine position or for facing thecradles. These bolts should he femoved after adjustment, the anchor bolts can then besecured.

I

Fig. 3-21 Main Bearings and the Thrust Bearing

Checking and Replacement of Main Bearings

The wear of a main bearing is quite little under normal operating conditions. However,heavier wear of some individual bearing should happen for any reason resulting indeflection of center line of the crankshaft. This increases the wear of other main bearings,as well as the bending stress nf the crankshaft ,even leads to the crankshaft rupture.Therefore, bearing inspection should be carried out in accordance with the intervalrecommended in Chapter 12. lf in any case abnormal condition is found, dismounting andinspecting should be done accordingly.

The bearing should be replaced if its clearance exceeding limit values or abnormal defectsexisted, such as alloy layer cracking or spallation, serious scarfing eic.

The normal thickness of the bearing shell is 6.381iijmm. lf the journal is seriously worn out,

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a thicker shell should be used. A replacennt shell need not be scraped. lf too much contactor too small clearance for replacing the bearing shell, the shell with a thickness of lower limitshould be chosen. Only in case such a shell still could not fit the case, the shell can thenbe scarped by skilled workers.

Certain crush height of the bearing shell is required, which had been strictly checked bybearing manufacturer and should not be filed or cut by the user.

lf the replacement work should be done inside the crankcase, it is essential not to removelower half shells of two adjacent main bearings, so as to ensure the crankshaft being wellsupported.

Removement of the main bearing cover inside the crankcase is carried out as follows (c.f.Fig 3-22)1. Turn the crankshaft to the position shown in Fig.3 -22.

2. Unscrew the nut of the main bearing bolts.

3. Remove the oil tube for the main bearing, install the tool (320.100.130A) for removingmain bearing cover.

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Fig. 3-22 Removing of Main Bearing cover inside the Grankcase

4. Rotating the two electing bo;ts (2) to eject the cover. Install rod (3) and plate (4) formoving the bearing cover. Carefully take out the main bearing cover and upper shell.

3-34

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ENGIN[: MAIN COMPONENTS

5. lf removing the lower shell (see Fig. 3-23),a tongued pin (5) is inserted into such an oilhole of the journal that the pin itself can not drop out dufing crankshaff turning. Turning thecrankshaft in the direction toward the dowel pin of the bearing shell, the lower shell can ihenbe removed. In the case of removing the shell of the main bearing adjacent to the flywheel,a tongued pin in right angle shape is inserted into the hole of the journal as shown inFig.3-23 to withdraw and install ihe shell.

For placing the bearing shell as follows:

1. The tongued pin is inserteci in the direction opposite to that in above point 4.

2. The lower bearing shell is placed on the main journa..

3. The main bearing tool is fitted as shown in Fig 3-23.The dowel pin (2) of the tool isinserted into the locating groove of the bearing seat, and is removed after the tool beingtightened.

Fig.3-23 Mounting and Fismounting of the Bottom Shell of the Main Bearing

Turn the crankshaft slowly to help the shell moving down until its half way and then thelimiter (6) and (8) is fitted to the main bearing bolt on the other side and tighten themwith nuts. Again slowly turn the crankshaft until one end of the shell is in contact withthe limiter. lt should be noted not to rotate the crankshaft too fast so as to avoid anypossible damage of the shell. lt must be sure at lhe beginning of crankshaft rotating,that the dowel pin of the shell should fit into the groove of the tool.

4.

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5. After removing the tongued pin, the upper shell is placed to the main bearing cover, towhich the tool is then fitted. The whole assembly is then placed on the bedplate. (seeFig. 3-2s)

6. Tighten the two main bearing bolts alternatively and uniformly in several times to reachthe specified torque.

7. Check bearing clearance and crank-web deflection ofthe crankshaft, measured resultsshould be in line with the soecified values.

8. The oil pipes are placed and secured.

It is also very important to be clean during the whole removing or placing process, no anymechanical particle is allowed to present in sliding surface.

3.2.2 Cyl inder Liner

The cylinder liner is made of alloy cast iron with good wearability. The upper flange is seatedon the supporting faces 16 mm above the top face of the cylinder block,a red copper ring isplaced between the flange and supporting. The part above the mid support also for locationis designed to be thinner than the lower part, cooling water can flow directly up to the areaclosed to the flange. Better heat rejection can thus be realized, leading to lower temperalurelevel of the upper part of the liner. There are three o-rings made of oil-proof rubber fitted inthree grooves of the lower locating surface. .A recess for fitting with the cylinder head is cuton top surface of the liner. The recess is just at the position of the supporting area of thecylinder block, this reduces the additional bending moment of the flange, preventing theflange from cracking during engine operation. Furthermore, concave rounded groove isadopted for kansition part of the flange to the cylindrical surface of the liner to eliminatestress concentration.

There is a pin in each cylinder li;rer for its locating on cylinder block. In inner surface of theliner bottom, there are two oppcsite machined recesses with an angle of 15' to the linercentral line, to avoid the liner being collided with the connecting rod as the engine inoperation.

The anti-polishing ring is sprayed in the inner surface of the upper part of the cylinder liner ofHFO engine in order to scrape the carbon in the upper part of the piston, and to reduce thewear of the cylinder liner and lube oil consumption, and to increase the gas-sealing of thecylinder liner and piston, and to reduce the pollution of the lube oil .

Maintenance and removing of Cylinder Liners

The cylinder liners should be cher:ked for scuffing for every 500 operating hours: To do this,

3-36

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turn the crankshafi until the piston being at T.D.C., open the observation window, andobserve the condition of the working surface by means of a mirror extended to near thecylinder liner su rface .

The exteriority of the liner should be checked via removing the water inlet cover for every2000 operating hours, lf serious corrosion is found, replace the cylinder liner with a new one.lf the depth of pits being less than 8 mm, tin repair welding is recommended. lf scale depositexceeds 1.5 mm in thickness, the liner should be removed for cleaning. In any case of thepiston-connecting rod assembly dismounted, the wear condition of the liner should bemeasured together with the piston before reassembling. The liner should be replaced if itswear extent being beyond the lin:its. The central line of a new liner should be normal to thatof the crankshaft. This can be checked by means of smear test if the supporting shouldersof the cylinder liner is in uniform contact circumferentially with the supporting face of theengine block. At the same time, the clearance between the lower matching surfaces of theliner and block should be checked by using a feeler gauge. The flange may be locallyscraped if necessary. In doing so, no O-ring is fitted. The bore corresponding to the areafifting O-rings should be measured after reassembling, where the deformation should be inline with specified values.

Dismounting of Gylinder Liners

1 . Drain off all cooling water in the engine block. Open the observation windows on bothsides of engine block.

2. Remove the cylinder head.

3. Remove the piston-connecting rod assembly.

4. Install tool No.320. 100. 90 for the cylinder liner as shown in Fig. 3-24. The right halfside of the diagram shows dismounting.

5. One by one or simultaneously turn the nut (2) on the tool until the liner coming intocontact with the beam.

6. Withdraw the liner from the engine block.

Mounting of Cylinder Liners

1. Fit new water sealing rubber ring with the rings projecting 0.4-0.6 mm from the linersurface, this can be obtained via filing the rings if necessary.

2. Place suitable annealed red copper ring on the concave of the support of the cylinderblock.

3-37


3.

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Fit the mounting tool to the liner as shown in the left ot Fig.3-24. Lift the liner andslowly put down into the cylinder block. The liner can fit into the counterbore via itsdeadweight or slightly pressing by hands.

Remove the tool and assemble the cylinder head. Hydrostatic test with a pressure ofo.7 Mpa should be carried out after tightening all bolts, and tightness of the o-rings andthe red copper ring should also be checked at the sarne time.

Fig. 3-24 Mounting and Dismotrnting of Cylinder Liners

3.2-3 Cylinder Heads and IG Accessories

3.2.3.1 Cyl inder Heads

The cylinder head is made of spherical graphite cast iron, and is tightened to the engineblock bv means of I studs.

3-38

ENGII{E MAIN COMPONENTS

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Fig. 3-25 Cylinder Head

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Documents

Guangzhou GDF 8320