work shop manual lgw 523-627 matr 1-5302-509

8/12/2019 Work Shop Manual LGW 523-627 Matr 1-5302-509

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WORKSHOP

MANUALSeries LGW 523-627 and LGW 627 GPL enginescode 1-5302-509

SERVICE

1

LGW 523LGW 627

1st Edition

COMPILER TECO/ATL REG. CODE

1-5302-509

MODEL N

50778

DATE OF ISSUE

10.06.99REVISION 00

ENDORSEDDATE

10.06.99


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SERVICE

FOREWORD

We have done all in our power to give up to date and accurate technical information in this manual. Lombardiniengines are, however, constantly developing thus the data in this publication may be liable to modification without

prior notice.

The information in this manual is the exclusive property of Lombardini. Neither partial nor total duplications orreprints are therefore permitted without the express authorization of Lombardini.

The information in this manual is given on the assumption that:

1- the persons who service Lombardini engines have been adequately trained and outfitted to safely andprofessionally carry out the necessary tasks;

2- the persons who service Lombardini engines possess the necessary skills and special Lombardini tools tosafely and professionally carry out the necessary tasks;

3- the persons who service Lombardini engines have read the specific information concerning the abovementioned Service operations and that they have clearly understood the operations required.

GENERAL SERVICE NOTES

1 - Only use genuine Lombardini spare parts. Use of spurious spares may lead to incorrect performance andshorten the life of the engines.

2 - The metric system is used to express all data, i.e. the dimensions are given in millimeters (mm), torque isexpressed in Newton-meters (Nm), weight in kilograms (Kg), volume in liters or cubic centimeters (cc) andpressure in barometric units (bar).


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MODEL N

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DATE OF ISSUE

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ENDORSEDDATE

10.06.993

WARRANTY CLAUSE

Lombardini S.r.l., guarantees its engines for a period of 12 months from the date of delivery to the first user, andno later than 24 months from the date of delivery to the manufacturer or building site. Of the two alternatives, theone that occurs first shall be considered valid.Stationary assemblies (with use at constant load and constant speed and/or with load and speed that slightly varywithin the regulating limits) are not covered by this clause. For these assemblies, the guarantee is recognized upto a maximum one thousand (1000) hours service if the above mentioned periods have not been exceeded.

In the case of special applications requiring considerable modifications to the cooling, lubricating (example: drysump systems), supercharging and filtering circuits, either the special warranty clauses explicitly established inwriting shall be valid or the above mentioned general clauses if an approval test of the application issued by theTechnical Management of Lombardini motori is exhibited.Within the above mentioned terms, Lombardini undertakes to supply, free of charge, spare parts for thosecomponents which are recognized by Lombardini or by one of its authorized representatives as possessingmanufacturing or material defects or, at its discretion, to either carry out repairs itself or by means of authorizedworkshops.

All other total and partial liability and obligation for other direct or indirect expenses, damages or losses derivingfrom use or the impossibility to use the engines shall, however, remain excluded.Repairs or supply of substitutions shall in no way extend or renew the length of the warranty period.

Expenses sustained to remove the engine from the machine or hull and to remount it again, plus transportexpenses and those for expendable materials (filters, lubricating oils, etc.) shall be at the user's charge.

Lombardini's obligations established in the previous paragraphs shall become void if:- The engines are not used in compliance with Lombardini's instructions in the operation and maintenance

manual;- The seals affixed by Lombardini are tampered with;- The engines are repaired, dismantled or modified by workshops that have not been authorized by Lombardini;- Use has been made of spares that are NOT genuine Lombardini parts;- The injection systems have been damaged by unsuitable or polluted fuel;- The electrical systems become faulty owing to components such as remote control relays, for which the

manufacturer's warranty is applicable.

Lombardini shall consider itself released from all liability and from the obligations described in the previousparagraphs once the twelve month period from the date on which the engine was delivered to the first users haselapsed and/or the thousand (1000) hours service have terminated.

This warranty, which runs from 1st July 1993, voids and substitutes all other expressed or implicit warranties andmay only be modified in writing.

WARRANTY CLAUSE


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MODEL N

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DATE OF ISSUE

10.06.99REVISION 00 DATE

10.06.99

ENDORSEDCOMPILER TECO/ATI

4

TABLE OF CONTENTS

I TROUBLESHOOTING

II SAFETY DECALS - SAFETY INSTRUCTIONS

III CODE AND IDENTIFICATION

IV TECHNICAL SPECIFICATIONS

V CHARACTERISTIC CURVES

VI OVERALL DIMENSIONS

VII MAINTENANCE- RECOMMENDED OIL - COOLANT FLUID - FUELS AND LUBRICANTS

VIII DISASSEMBLY / REASSEMBLY

Bearing half-rings, oversizesBelt tightening guide pulleyCam height inspectionCamshaft and housings, pin dimensions (mm)Camshaft, demountingCamshaft, inspection of pin diameters and housingsCentral main bearing caps

Checking for play between bearings and main journalsConnecting rod (big-end bearing)Connecting rod complete with bearings and pinConnecting rod, weightConnecting rod alignmentCooling fanCooling fan and alternator beltCylinder head, removalCylindersCylinders, classCylinders, roughnessCrank shaft floatCrank shaft front and rear oil retention sealsCrank shaft, lubrication ductsCrank shaft, main journal and crank inspectionDemounting and remounting the pin stop ringsDemounting the oil pumpDiameters of main journal and big-end journalsDriving pulleyExhaust manifoldFlywheelHead gasketHead torquingHydraulic pump drive (for LGW 627)Inner diameters of main and big-end bearingsIntake, exhaust cam height - LGW 523 - LGW 627LGW 523 - LGW 627 remote dry air filterLGW 523 - LGW 627 valve springsLGW 523 - LGW 627 valve/rocker clearanceLGW 523 Dry air filter

This manual contains information on how to repair LOMBARDINI LGW 523, LGW 627 gasolinefuelled engines and LOMBARDINI LGW 627 LPG fuelled engines and is up to date as of10.06.1999.

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TABLE OF CONTENTS


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TABLE OF CONTENTS

LGW 523 bleedLGW 523 dry air filterLGW 523 rocker capLGW 523-627 head torquing phasesLGW 627 air filter supportLGW 627 dry air filter

LGW 627 rocker capLGW 627 speed governorLGW 627 speed governor componentsLGW 627 speed governor leversOil pumpOil retainer seal in valve guide, removalOil sump, removalOperative timing system tuning angles (valve clearance = 0.26 mm) for LGW 523Operative timing system tuning angles (valve clearance = 0.26 mm) for LGW 627PistonPiston protrusion testPiston rings - Distance between the tipsPiston rings, assembly orderPiston rings, play between slots (mm)

Piston, class and logotypePiston, demounting and inspectionPiston, refittingPistons, weightPulley on crank shaftRear and front main bearing capsRemounting the LGW 627 speed governorRemounting the oil pumpRemoving the timing beltRocker cap and recirculated oil vapour bleeding system for engine LGW 627Rocker shaftRocker shaft, demounting and refittingSupporting half-ringsTank (on request)Third drive, components (for LGW 627)Timing belt and gearsTiming belt guardTiming pulley - Disassembly/ReassemblyTiming pulley - Timing system tuning reference marksTransmission pulleyTuning angles to check the timing system (valve clearance = 2 mm) for LGW 523Tuning angles to check the timing system (valve clearance = 2 mm) for LGW 627Tuning the timing system - AnglesTuning the timing system - Belt tightening toolTuning the timing system - InspectionTuning the timing system - Refitting the timing beltTuning the timing system - Tightening the timing belt and tightener torqueValve guides and housingsValve guides, assemblyValve recessing and width of housing sealValvesValve springsValves, seats and housingsValves, specifications

IX LUBRICATION CIRCUIT

Internal oil filter and engine oil return tubeLubrication circuitOil filter cartridgeOil pressure check

Oil pressure regulating valveOil pumpOil pump, play between rotors

291929382019

2826262627323425253537363636

35353736234126272328303041214422222324222525252425242433333432333433

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TABLE OF CONTENTS

X COOLING CIRCUIT

Cooling circuitCooling fluid pump, componentsRadiator and compensation chamber plug - Inspections and tightnessThermostatic valve

XI FUELLING CIRCUIT

AdjustmentsAdjustments and calibrationCalibrated partsCarburetorCarburetor 32TLF/250Carburetor FHCD22.18ECarburetor LGW 523Carburetor vacuum adjustmentCarburetor vacuum adjustmentCarburetor vacuum balancing testCarburetor with variant to keep the engine idling when coldCold startingEnrichment adjustments - with analyzerFloat chamber levelFuel filter detached from tankFuel pumpFuel pump rod projectionHigt and idling speed adjustmentIdling adjustmentIdling speedFuelling circuitInspections and adjustmentsMixture adjuster screw regulation (idling rate)Normal speed

Partial air powered opening of the ignition throttlePick-upPick-up pump deliveryPositive openingPreliminary conditionsSpeed adjuster screw regulation (idling rate)

XII IGNITION

523 ignition processIntroductionLGW 523 coilLGW 523 cut-offLGW 523 ignition systemLGW 627 ignition systemMain components of the LGW 523 ignition systemMain components of the LGW 627 ignition systemOperating principleOperating principlePhase sensorSpark plug (type Champion RC 12YC)Technical specifications of the ignition module

XIII ELECTRICAL CIRCUIT

Alternator housed in the flywheelAlternator Iskra 14V 33A

BatteryBattery recharging curve for 12V 20A alternator

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TABLE OF CONTENTS

Battery recharging curve for 12V 30A alternatorCharacteristic curve of alternator Marelli AA 125 R 14V 45ACharacteristic curve of starter motor Bosch type DW 12V 1.1 kWCharacteristic curve of the Iskra 14V 33A alternatorIgnition module of gasoline (petrol) and LPG fuelled engine LGW 627 with spark lead variationdevice serial N122.2193.114

Ignition module of gasoline (petrol) fuelled engine LGW 523 with idling back-up device serial N122.2193.113Ignition module of gasoline (petrol) fuelled engine LGW 523 without idling back-up device serial N122.2193.108Ignition module of gasoline (petrol) fuelled engine LGW 627 with spark lead variation device serialN 122.2193.109Ignition module of gasoline (petrol) fuelled engine LGW 627 with spark lead variation device serialN 122.2193.114Marelli alternator, type AA 125 R 14V 45APressure switch for oil pressure indicatorSensor for coolant fluid temperature indicatorStarter motor, Bosch type DW 12V 1.1 kWVoltage regulator connectionWiring diagram of gasoline (petrol) fuelled engine LGW 523 with idling back-up device, with internal

alternator and module serial N122.2193.113Wiring diagram of gasoline (petrol) fuelled engine LGW 523 withour idling back-up device, withinternal alternator and module serial N122.2193.108Wiring diagram of gasoline (petrol) fuelled engine LGW 627 with external alternator and moduleserial N 122.2193.109Wiring diagram of gasoline (petrol) fuelled engine LGW 627 with external alternator and moduleserial N 122.2193.114Wiring diagram of LPG fuelled engine LGW 627 with external alternator and module serial N122.2193.114

XIV STORAGE

Permanent protection (longer than 6 months)Preparing for operationStorageTemporary protection (1/6 months)

XV LPG fuelled ENGINE LGW 627

Carburation test with exhaust gas analyzerChange-over switch Mod. 093Components of the LPG conversion unitConnecting the mixer to the regulatorElectrical system

Gasoline (petrol) solenoid valveHow to regulate the sensitivity of reducer SE 81 SICLiquid phase LPG shut-off solenoid valveMod. 093 change-over switch installationOperation of the ignition system for gasoline (petrol) or LPG fuelled enginesOperation of the LPG conversion unitPositioning the regulatorRegulator heating circuit connectionRegulator installationRegulator/atomizerRegulating procedure with reducer SE 81 SICTechnical specificationsThe mixer

76757774

69

73

71

65

677577777775

72

70

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66

68

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TABLE OF CONTENTS

XVI MAIN DRIVING TORQUES

Driving torques for standard screwsMain driving torquesUse of sealing agents

XVII SPECIFIC TOOLS

Specific tools

90

919090

" 92

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The table gives the causes of some of the faults that may occur during operation.Proceed systematically with the simplest inspections before removing or replacing any parts.

D I S A S S E M B L Y / R E A S S E M B L Y

A D J U S T M E N T S

M A I N T E -

N A N C E

E L E C T R I C A L

C I R C U I T

L U B R I C A T I O N

C I R C U I T

F U E L

C I R C U I T

PROBABLE CAUSES AND THEIR REMEDIES

Clogged tubesFuel filter cloggedAir in the fuel circuitTank plug venting hole cloggedDefective fuel pumpFuel dirty or containing waterCarburetor incorrectly regulatedDirty carburetorOil level too highPressure regulating valve jammed or dirtyWorn oil pumpAir in oil intake pipeDefective pressure gauge or pressure switchOil intake pipe cloggedOil filter cloggedElectronic module defective"Hall" module sensor faultyBattery lowWiring uncertain or incorrectDefective ignition switchDefective starter motorDefective coilSpark plug grounded or defectiveSpark plug cable disconnectedCut-Off defective or disconnected

Air filter cloggedCoolant fluid radiator cloggedCoolant fluid level low or containing airEngine overloaded

Speed governor levers incorrectly timedSpeed gov. spring broken, released or unsuitableIdling rate too lowPiston rings worn or jammedCylinders worn or scoredValve guides wornFaulty valve housingsValves jammedWorn connecting rod journal bushesGovernor levers not free to slideDrive shaft not free to slideDamaged big-end sealsTiming belt broken

PROBABLE CAUSE

FAULTS

I r r e g u

l a r s p e e

d

F a i l s t o a c c e

l e r a

t e

S t a r t s

t h e n s t o p s

F a i l s t o s t a r

t

B l a c k s m o k e

W h i t e s m o k e

L o w o i

l p r e s s u r e

H i g h o i

l p r e s s u r e

E x c e s s i v e

o i l

c o n s u m p

t i o n

O i l a n

d f u e l

d r i p f r o m e x

h a u s

t

C o o l a n

t

f l u i d o v e r

h e a t s

TROUBLESHOOTING I


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Failure to comply with theinstructions could result indamage to persons and

property

Failure to comply with theinstructions could lead totechnical damage to the

machine and/or system

DANGER

SAFETY AND WARNING DECALS

CAUTION

SAFETY INSTRUCTIONS

Lombardini Engines are built to supply their performances in a safe and long-lasting way. To obtain these results,it is essential for users to comply with the servicing instructions given in the relative manual along with the safetyrecommendations listed below.

The engine has been made according to a machine manufacturer's specifications and all actions required to meetthe essential safety and health safeguarding requisites have been taken, as prescribed by the current laws in merit.All uses of the engine beyond those specifically established cannot therefore be considered as conforming to theuse defined by Lombardini which thus declines all liability for any accidents deriving from such operations.

The following indications are dedicated to the user of the machine in order to reduce or eliminate risks concerningengine operation in particular, along with the relative routine maintenance work.

The user must read these instructions carefully and become familiar with the operations described. Failure to dothis could lead to serious danger for his personal safety and health and that of any persons who may be in the vicinityof the machine.

The engine may only be used or assembled on a machine by technicians who are adequately trained about itsoperation and the deriving dangers. This condition is also essential when it comes to routine and, above all,extraordinary maintenance operations which, in the latter case, must only be carried out by persons specificallytrained by Lombardini and who work in compliance with the existing documentation.

Variations to the functional parameters of the engine, adjustments to the fuel flow rate and rotation speed, removalof seals, demounting and refitting of parts not described in the operation and maintenance manual by unauthorizedpersonnel shall relieve Lombardini from all and every liability for deriving accidents or for failure to comply with thelaws in merit.

On starting, make sure that the engine is as horizontal as possible, unless the machine specifications differ. In thecase of manual start-ups, make sure that the relative actions can take place without the risk of hitting walls ordangerous objects, also considering the movements made by the operator. Pull-starting with a free cord (thusexcluding self-winding starting only), is not permitted even in an emergency.

Make sure that the machine is stable to prevent the risk of overturning. Become familiar with how to adjust the rotation speed and stop the engine.

Never start the engine in a closed place or where there is insufficient ventilation. Combustion creates carbonmonoxide, an odourless and highly poisonous gas. Lengthy stays in places where the engine freely exhausts thisgas can lead to unconsciousness and death.

II SAFETY AND WARNING DECALS - SAFETY INSTRUCTIONS


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The engine must not operate in places containing inflammable materials, in explosive atmospheres, where there isdust that can easily catch fire unles specific, adequate and clearly indicated precautions have been taken and havebeen certified for the machine.

To prevent fire hazards, always keep the machine at least one meter from buildings or from other machinery. Children and animals must be kept at a due distance from operating machines in order to prevent hazards

deriving from their operation. Fuel is inflammable. The tank must only be filled when the engine is off. Thoroughly dry any spilt fuel and move

the fuel container away along with any rags soaked in fuel or oil. Make sure that no soundproofing panels madeof porous material are soaked in fuel or oil. Make sure that the ground or floor on which the machine is standinghas not soaked up any fuel or oil.

Fully tighten the tank plug each time after refuelling. Do not fill the tank right to the top but leave an adequatespace for the fuel to expand.

Fuel vapour is highly toxic. Only refuel outdoors or in a well ventilated place. Do not smoke or use naked flames when refuelling. The engine must be started in compliance with the specific instructions in the operation manual of the engine

and/or machine itself. Do not use auxiliary starting aids that were not installed on the original machine (e.g.Startpilot).

Before starting, remove any tools that were used to service the engine and/or machine. Make sure that all guards

have been refitted. During operation, the surface of the engine can become dangerously hot. Avoid touching the exhaust system in

particular. Before proceeding with any operation on the engine, stop it and allow it to cool. Never carry out any operation

whilst the engine is running. The coolant fluid circuit is under pressure. Never carry out any inspections until the engine has cooled and even

in this case, only open the radiator plug or expansion chamber with the utmost caution, wearing protectivegarments and goggles. If there is an electric fan, do not approach the engine whilst it is still hot as the fan couldalso start operating when the engine is at a standstill. Only clean the coolant system when the engine is at astandstill.

When cleaning the oil-cooled air filter, make sure that the old oil is disposed of in the correct way in order tosafeguard the environment. The spongy filtering material in oil-cooled air filters must not be soaked in oil. The

reservoir of the separator pre-filter must not be filled with oil. The oil must be drained whilst the engine is hot (oil T ~ 80C). Particular care is required to prevent burns. Donot allow the oil to come into contact with the skin.

Make sure that the drained oil, the oil filter and the oil it contains are disposed of in the correct way in order tosafeguard the environment.

Pay attention to the temperature of the oil filter when the filter itself is replaced. Only check, top up and change the coolant fluid when the engine is off and cold. Take care to prevent fluids

containing nitrites from being mixed with others that do not contain these substances since "Nitrosamine",dangerous for the health, can form. The coolant fluid is polluting and must therefore be disposed of in the correctway to safeguard the environment.

During operations that involve access to moving parts of the engine and/or removal of rotating guards,disconnect and insulate the positive wire of the battery to prevent accidental short-circuits and to stop the startermotor from being energized.

Only check belt tension when the engine is off. Only use the eyebolts installed by Lombardini to move the engine. These lifting points are not suitable for the

entire machine; in this case, the eyebolts installed by the manufacturer should be used.

SAFETY AND WARNING DECALS - SAFETY INSTRUCTIONS II


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III CODE AND IDENTIFICATION

Max speed

setting(r/min)Type of engine

Serial N

Performance approval

N of version(K modulus)

Exhaust approvals

Note: The Performance Approval and Exhaust Approvals areonly stamped for Diesel engines


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CylindersBoreStrokeDisplacementCompression ratior/min

N 80/1269/EEC - 88/195/EEC - ISO 1585Power kW/HP NB 80/1269/EEC - ISO 1585

NA ISO 3946/1 - ICXNMaxim um torqueNo-load idling speed r/ minWater pump flow rate

Max. tolerated inclination for intermittant service ***Specific fuel consumptionStandard oil sump capacity (filter included)Standard oil sump capacity (filter excluded)Oil consumption (measured at N power rating) *Oil consumption (measured at NA power rating) **Recommended batteryDry weight

IVTECHNICAL SPECIFICATIONS

LGW 523-627 SPECIFICATIONS

TYPE OF ENGINE

Nmmmmcc.

Nm

l/min

g/kWl.l.

g/kWhg/kWh

V/ahKg

* In N power SELF-DRIVING POWER: Discontinuous service at variable rate and load.** In NA power CONT. OVERLOADABLE POWER: Continuous heavy-duty service at constant rate and load.*** Depending on application

LGW523 LDW 627

27262

5058.7 : 1500 0

15 / 20.4

37 @ 2200110052 (~)

at 5000 rpm25 (35)

3001.51.4

0.007

12/4452

27275

6119 : 13600

14.5 / 19.7

12.3/16.744.5 @ 2400

110040 (~)

at 3600 rpm25 (35)

3101.71.6

0.00712/44

60

LGW 523

LGW 627


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CHARACTERISTIC CURVESV

CHARACTERISTIC POWER, DRIVING TORQUE AND SPECIFIC CONSUMPTION CURVES

N (80/1269/CEE - ISO 1585) SELF-DRIVING POWER : Discontinuous service at variable rates and loads.NB (ISO 3046 - 1 IFN) NON-OVERLOADABLE POWER: Continuous light service at constant rate and with variable loads.NA (ISO 3046 - 1 ICXN) CONTINUOUS OVERLOADABLE POWER: Continuous heavy-duty service at constant rates and loads.MN Torque curve (in curve N)

Mt (in curve N)MA (in curve NA)C Specific consumption curve measured at power NBCse Specific consumption curve measured at power N

The indicated power ratings refer to engines equipped with air filter, standard silencer and fan, with the running-in period terminated and atenvironmental conditions of 20C and 1 bar.Maximum power is guaranteed with a 5% tolerance.The power ratings drop by about 1% for every 100 m of altitude and by 2% for every 5C above 25C.

Note: Consult LOMBARDINI for power, torque curves and specific consumptions at rates differing from those given above.

LGW 523 LGW 627

Remember that all variations to the intake or exhaust systems during the application phase of engines LGW 523 andLGW 627 will involve a variation in the carburation.Optimizing must be checked beforehand in the Lombardini test departments. Failure of Lombardini to approve this typeof modification relieves the same from all liability for any damage the engine may sustain.


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VIOVERALL DIMENSIONS

Note : The values are in mm

LGW 627

LGW 523


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VII

10 50 80 100 175 250 350 500 1000 2000 5000

FREQUENCY HOURSPARTOPERATION

SUMP OIL LEVELRADIATOR FINSALTERNATOR BELT TENSIONVALVE AND TAPPET PLAYAIR FILTERCARBURETORSUMP OIL LEVELANTI-FREEZE (****)OIL FILTER CARTRIDGEFUEL FILTERAIR FILTER CARTRIDGETIMING BELT (**)FAN (ALTERNATOR) BELTSPARK PLUGPARTIAL (***)GENERALCARBURETOR

First change(*) In very dusty environments(**) When the timing belt is removed it must be changed even though it has not terminated its period of use.(***) Check the cylinders, piston rings, guides, springs and valve seat honing; descale cylinder head and cylinders.(****) Every two years or after 1000 hours service.

INSPECTION

REPLACEMENT

OVERHAUL

Failure to carry out the operations described in the table may lead to technical damage to the machineand/or system

MAINTENANCE - RECOMMENDED OIL - COOLANT FLUID - FUELS AND LUBRICANTS

LGW 523 ENGINE MAINTENANCE

10 50 80 100 175 250 350 500 1000 2000 5000

FREQUENCY HOURSPARTOPERATION

OIL-COOLED AIR FILTERFUEL TANK

AIR FILTER OILLEVEL SUMP OIL

BATTERY FLUIDRADIATOR FINSALTERNATOR BELT TENSIONVALVE AND TAPPET PLAYAIR FILTERCARBURETORS

AIR FILTER (*)(**)SUMP

ANTI-FREEZE (*****)OIL FILTER CARTRIDGEFUEL FILTERAIR FILTER CARTRIDGETIMING BELT (***)ALTERNATOR BELTSPARK PLUGPARTIAL (****)GENERALCARBURETORS

First change(*) In very dusty environments

(**) See recommended type of oil(***) When the timing belt is removed it must be changed even though it has not terminated its period of use.(****) Check the cylinders, piston rings, guides, springs and valve seat honing; descale cylinder head and cylinders.(*****) Every two years or after 1000 hours service.

CLEANING

INSPECTION

REPLACEMENT

OVERHAUL

OIL

LGW 627 ENGINE MAINTENANCE

(*)

(*)

(*)

(*)

(*)


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GRADERECOMMENDED OIL

AGIP SINT 2000 5W40 specification API SJ/CF ACEA A3-96 B3-96

MIL-L-46152 D/E.ESSO ULTRA 10W40 specification API SJ/CF ACEA A3-96 MIL-L-46152 D/E.In countries where AGIP and ESSO products are not available, useAPI SJ/CF oil for gasoline-fuelled engines or oil that complies withmilitary specification MIL-L-46152 D/E.

OIL SUPPLY ( liters ) 523Standard oil sumpfilter included 1.5filter excluded 1.4

OIL SUPPLY ( liters ) 627Standard oil sumpfilter included 1.7filter excluded 1.6

ACEA SEQUENCES

A = Gasoline (Petrol)B = Light Diesel fuelsE = Heavy Diesel fuels

Required levels :

A1-96A2-96A3-96

B1-96B2-96B3-96

E1-96E2-96E3-96

-30

-25

-20

-15

-10

-5 0

+5

+10

+15

+20

+25

+30

+35

+40

+45

SAE 20W

SAE 10W

+50

SAE 30SAE 40

SAE 10W-30

SAE 10W-40

SAE 10W-60

SAE 15W-40 mineral based

SAE 15W-40 semi-synthetic based

SAE 20W-60 semi-synthetic basedSAE 5W-30 synthetic based

VIIMAINTENANCE - RECOMMENDED OIL - COOLANT FLUID - FUELS AND LUBRICANTS

CCMC G- 2

CF CE CD CC CB CA SA SB SC SD SE SF SG

DIESELBENZINA - ESSENCE - PETROL

BENZIN - GASOLINA -

CCMC G- 3 G- 5CCMC PD - 1 / PD - 2

CCMC D- 2D- 4CCMC D- 3D- 5

MIL - L - 2104 DMIL - L - 2104 E

MIL - L -46152 CMIL - L- 46152 D/E

MB 226.1 MB 226.5MB 227.1 MB 227.5

228.3 MB 228.1

VW 501.01VW 500.00

VOLVO VDS

MAN QC 13-017

VW 505.00

SHAPI

The engine could be damaged if allowed to operate with insufficient oil. It is also dangerous to add too much oil as itscombustion could sharply increase the rotation speed.Use a suitable oil in order to protect the engine.The lubrication oil influences the performances and life of the engine in an incredible way.Use of an inferior quality oil or failure to regularly change the oil will increase the risk of piston seizure, may make thecompression rings jam and will lead to rapid wear on the cylinder liner, the bearings and all other moving parts. Engine life

will also be notably reduced.Oil viscosity must suit the ambient temperature in which the engine operates.

Old oil can cause skin cancer if repeatedly left in contact with the skin and for long periods of time. If contact with the oilis inevitable, you are advised to thoroughly wash your hands with soap and water as soon as possible.Appropriate protective gloves etc should be wore during this operation.Old oil is highly polluting and must be disposed of in the correct way. Do not litter.

G- 4

SJ

SAE 0W-30 synthetic basedSAE 5W-40 synthetic based

-35

-40


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VII MAINTENANCE - RECOMMENDED OIL - COOLANT FLUID - FUELS AND LUBRICANTS

The fluid coolant circuit is pressurized. Inspections must only be made when the engine has cooled and even in thiscase, the radiator or expansion chamber plug must be unscrewed with the utmost caution.If an electric fan is installed, do not approach a hot engine since the fan itself could start up even when the engine is ata standstill.Coolant fluid is polluting. It must therefore be disposed of in the correct way. Do not litter.

COOLANT FLUID

Remember to use anti-freeze and protective fluids (e.g. (es. AGIP ANTIFREEZE, ESSO PERMANENT ANTIFREEZE, etc.)mixed with decalcified water for preference.The freezing point of the coolant fluid mixture depends on the concentration of the product in water: at -15 ( 30% ), at -20C( 35 % ), at -25C ( 40 % ), at -30C ( 45 % ), at -35C ( 50 % ).Besides lowering the freezing point, permanent liquid also raises the boiling point. This passes from 100C (point at whichwater boils) to temperatures of over 110C. The boiling point varies according to the characteristics of the fluid and dependingon the pressure in the circuit itself.It is therefore advisable to use a mixture diluted by 50% to ensure a general degree of protection.

COOLANT FLUID SUPPLY ( liters )

With standard radiator LGW 523 - 627 l. 2.3


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DISASSEMBLY/REASSEMBLY VIII

DISASSEMBLY AND REASSEMBLY

Besides describing how to dismantle and reassemble the variousparts, this chapter also includes instructions on how to check andtune the engines, dimensions, repairs and hints on operation.Always use genuine LOMBARDINI spares to correctly repair the

engines.

LGW 523 Dry air filter

The dry air filter of engine LGW 523 consists of a single unit (casingand cartridge) which cannot be separated.Since the internal cartridge cannot be cleaned, the whole filter mustbe changed.To remove the old filter, unscrew screw 1 (clamp that fixes it to thecarburetor) and screw 2 ( clamp that fixes the breather pipe).To fix seal 3 (see fig. 1), thoroughly clean and and degrease the

housing on the carburetor and apply Loctite 401 adhesive.Consult page 16 for the maintenance (replacement) instructions.

Never clean the filtering element using solvents with a lowflash point. This could cause an explosion !

It is inadvisable to blow compressed air on to the paper filterelement.If necessary, lightly and repeatedly tap the element on a hardsurface to eliminate any excess dirt.

LGW 627 Dry air filter

Parts: 1 Cover2 Filtering cartridge3 Support4 Vent

Cartridge specifications:Filtering degree = 13 to 14 micron m.Filtering area = 4470 cmSee page 16 for the maintenance or replacement instructions.

LGW 627 Air filter support

The exhaust manifolds are built into the support.To remove the support, unscrew the 4 nuts 1 and disconnect thebleed pipe between the manifold and the rocker cover.When remounting the parts, re-connect the bleed pipe, tighten therelative clamps and then torque the 4 nuts 1 to 4 Nm.

3

1

2

Always wear protective goggles during repairwork, when compressed air is used


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LGW 627 Air filter support

1 Air filter support2 Oil vapour venting tube from the tappet cap to the air filter support3 Tube that returns the vapour, re-converted into liquid oil, back to

the sump

Whenever the intake manifold is demounted, make sure that thereare no traces of dust either in the manifold itself or in the intakepipes.Replace the seals between the carburetors and manifold wheneverthe support is demounted.

LGW 523 - LGW 627 Remote dry air filter

Configuration example of remote air filters for the two engines inquestion.4 or 5 inch filtering elements can be used.

LGW 523: 1 Remote air filter (4 or 5 inches)2 Clamp3 Connection pipe from the carburetor cap to the air filter4 Clamp5 Carburetor cap

LGW 627: 1 Remote air filter (4 or 5 inches)2 Clamp3 Connection pipe from the intake manifold to the air

filter4 Clamp5 Intake manifold6 Bleed pipe from the intake manifold to the rocker cap

Allow the exhaust manifold to cool before demounting it inorder to prevent scorching and burns.

Exhaust manifold

When the exhaust manifold is demounted, make sure that theinterior is perfectly clean and free from cracks or fractures.Replace the seals whenever the manifold is remounted.Torque the fixing nuts to 25 Nm when the parts are remounted.

DISASSEMBLY/REASSEMBLYVIII

6

5

4

When engines LGW 523 and LGW 627 are being installed, remember that any variation to the intake system (type ofair filter, length and diameters of the pipes leading from the intake manifold to the air filter) will involve a modification tothe carburation.The carburation must be tested beforehand in the Lombardini test department. Failure of Lombardini to approve thistype of modification shall relieve the same of all liability for deriving operating faults and any damage to which theengine may be subjected.

When engines LGW 523 and LGW 627 are being mounted, remember that any variations to the exhaust system (typeof exhaust silencer, length and diameters of the pipes that lead from the exhaust manifold to the silencer) will involve avariation to the carburation.The carburation must be tested beforehand in the Lombardini test department. Failure of Lombardini to approve thistype of modification shall relieve the same of all liability for deriving operating faults and any damage to which theengine may be subjected.


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Transmission pulley

Remove the pulley by taking out screw 1 of fig. 12.

Components:

1 Screw 6 Ball bearing2 Washer 7 Spacer3 Centering bush 8 Ball bearing4 Pulley 9 Circlip5 Circlip

Note: To remount, thoroughly clean the thread of screw 1 andtorque to 25 Nm.

Always lock the crank shaft and not the other enginecomponents to loosen or tighten screw 1 to the requiredtorque value.

Driving pulley

Lock the drive shaft in the following way: demount the starter motorand mount tool 7107-1460-051 in its place (see page 92).To remove the pulley, slacken off the central screw 1 and proceedwith the four side screws 2.The central screw 1 is unscrewed in a clockwise direction. Whenremounting, apply "Moly-slip" anti-seize to the screw thread andtorque to 360 Nm.

Note: When reference mark A coincides with B, the piston of thecylinder on the flywheel side (first cylinder) will be at top deadcenter ( TDC ).

Timing belt guard

Unscrew the five screws and remove the guard.Torque the screws to 10 Nm when remounting.Check the rubber seal 2 and the two dust seal rings of the twopulleys 1 if mounted.

Timing belt and gears

Components:

1 Camshaft timing belt2 Timing belt3 Crank shaft timing pulley4 Coolant fluid pump gear5 Belt tightening guide pulley

16

12 13

14

15


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VIIIDISASSEMBLY/REASSEMBLY

If the timing belt is removed, it must be replaced even thoughit has not terminated its forecast period of use.Always make sure that the battery + is well disconnected.

Removing the timing belt

Unscrew the screw of the tightening pulley 1 and remove the belt bypulling it from the timing pulley on the camshaft.Consult page 16 for the frequency with which the belt must bereplaced.Consult page 16 when remounting.

Belt tightening guide pulley

Components:

1 Nut2 Washer3 Belt guide pulley4 Ball bearing5 Shaft6 Bearing plate7 Timing belt tightening lever.

Torque nut 1 to 40 Nm when remounting.

Pulley on crank shaft

Make sure that the key remains in its housing when remounting.

Note: reference mark 1 on the timing pulley and reference mark 2on the oil pump casing are used to tune the timing system.When the two reference marks are aligned, the piston of thecylinder on the flywheel side (first cylinder) will be at top deadcenter.A puller is not required for demounting.

Timing pulley - Disassembly/Reassembly

Unscrew screw 1 and remove the timing pulley. A puller is notrequired.Torque the screw to 80 Nm when remounting.

Note: Check for possible wear caused by the lip of the retention ringon the pulley hub.

22

17 18

19 20

21


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Timing pulley - Timing system tuning reference marks

1 Timing system tuning reference mark for LGW 523 and LGW 6272 Timing system tuning reference mark for LGW 5233 Timing system tuning reference mark for LGW 627.

Only remove the timing belt from its protective casing justbefore assembly.

Tuning the timing system - Refitting the timing belt

Match the reference marks on both the timing pulley fig. 23 anddriving pulley fig. 21.Insert the timing belt as shown in fig. 24, complying with thedirection shown by arrows A on it. The arrows must indicate therotation direction (clockwise) as viewed from the timing system side.Tighten nut 1 by hand until the belt tightener rests on the surface ofthe engine block.Belt remounting must begin with the camshaft pulley and then passto that of the drive shaft, not the driven shafts.

Tuning the timing system - Belt tightening tool

Fit tool 1 Serial N7107-1460-049 (see page 92) into lever 2.

Tuning the timing system - Tightening the timing belt and belttightener torque

Fit the torque wrench into the above mentioned tool so that axis A ofthe wrench fig. 27 is 90to axis B of the tool in fig. 26.Torque to 20 Nm in a clockwise direction. Maintaining the belttightened in these conditions, torque nut 3 to 40 Nm with anothertorque wrench.After having remounted the single-race pulley, turn the crank shaft afew turns and make sure that the obtained belt tension is asdescribed above.A further belt tension test can be conducted with a special tension

gauge available on the market (type ND DENSE).Belt tension must be 15 2 Kgm.

23

24 25

27

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Tuning the timing system - Inspection

A = Intake valveB = Exhaust valve

Move piston N1 (the one on the flywheel side) to top dead center.

Make sure that intake and exhaust valves A and B are balanced bysetting the touch probes of the two dial gauges on the valve caps.

Tuning the timing system - AnglesThe values of the angles can be identified by turning the crank shaftin a clockwise direction (viewed from timing system side).

S = Piston at top dead centerI = Piston at bottom dead centeraaaaa = Intake valve openingbbbbb = Intake valve closingggggg = Exhaust valve openingddddd = Exhaust valve closing

Operative timing system tuning angles (valve clearance = 0.26mm) for LGW 523

aaaaa = 38before Sbbbbb = 58after Iggggg = 70before Iddddd = 26after S

Tuning angles to check the timing system (valve clearance = 2mm) for LGW 523

aaaaa = opens 2after Sbbbbb = closes 18after Iggggg = opens 30before Iddddd = closes 14before S

Operative timing system tuning angles (valve clearance = 0.26mm) for LGW 627

aaaaa = 18before Sbbbbb = 62after Iggggg = 52before Iddddd = 28after S

Tuning angles to check the timing system (valve clearance = 2mm) for LGW 627

aaaaa = opens 22after S

bbbbb = closes 22after Iggggg = opens 12before Iddddd = closes 12before S

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LGW 627 speed governor

the speed governor is a mechanical type with centrifugal weights.It is installed behind aluminium support A fig. 30 and is drivendirectly by the camshaft.

Components:

1 Support with 4 weights2 Sliding sleeve3 Axial needle bearing4 Thrust plate

LGW 627 speed governor components

1 Oil retainer ring 2 Support

3 Screw 4 O-Ring 5 Ball bearing 6 Circlip 7 Flat ring 8 Screw 9 Support with 4 weights10 Sliding sleeve11 Axial needle bearing12 Thrust plate

LGW 627 speed governor levers

1 Governor control rod 2 Governor fork lever 3 Pin 4 O-Ring 5 Governor spring 6 Accelerator lever 7 Accelerator rod 8 Intermediate rod 9 Governor spring holes (the various holes are used to modify the

speed drop with the same spring)10 Accelerator support bracket

When remounting, make sure that all components are in agood condition and perfectly functional.A badly operating speed governor can seriously damage theengine and any bystanders in the vicinity.

Remounting the LGW 627 speed governorFit all parts in place by reversing the order shown in fig. 32.When the governor support is inserted into the camshaft, make surethat the four weights enter in an open position so that they can takeup the sleeve and close on top of it.To tune the speed governor with the carburetor, remember thatcarburetor throttles (gas valves) fully open - governor weights allclosed.

Make sure that the O-Ring of the support and the oil retainer ring arein a good condition. Torque the three screws to 10 Nm.Note: When the speed governor is mounted, camshaft float must be

nill.

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30 31

32

33


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VIII

Old engine oil can cause skin cancer if repeatedly left in contactwith the skin and for long periods of time. If contact with the oil isunavoidable, you are advised to wash your hands with soap andwater as soon as possible.Dispose of old oil in the correct way as it is highly polluting.Donot litter.

Demounting the oil pump

The oil pump is tested before and after assembly. Do not open itunless you are sure that it is faulty.To demount the pump, first remove the fixing bolts from the engineblock and set the piston of cylinder N 1 (flywheel side) to top deadcenter.These conditions allow key A to pass through cavity B.

Oil pump

Details and components:

1 Outer casing of oil pump (in aluminium)2 O-Ring3 Oil pump cover (in steel)4 Gasket between oil pump and engine block5 Centering pins6 Bolt to fix oil pump to engine block7 Bolts to fix oil pump to engine block8 Countersunk screw to fix pump cover to pump casing

Remounting the oil pump

The pump lobes should be coupled from the same side. Seereference marks 2 and 3.Replace ring 1.Tighten the fastening bolts to the engine block with a 25 Nm torque.Fixing bolt 6 (see fig. 35a) is different in length from the others andshould be tightened to a 20 Nm torque.The oil pump specifications are shown in figs. 114-115-116.

35

DISASSEMBLY/REASSEMBLY

35a

36


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37

39

38

LGW 627 rocker cap

Many of the more important engine components are on the cylinderhead.The rocker cover houses part of the camshaft lubrication duct, thatof the rockers and part of the engine bleeding system.

External parts of the rocker cover:

1 Screw to fix the rocker cover to the cylinder head2 Pressure switch (the only point where the engine oil pressure can

be gauged)3 Oil fill plugTighten the fixing bolts to a 9 Nm torque when remounting the cover.

Rocker cover and recirculated oil vapour bleeding system forengine LGW 627

Internal parts of the rocker cover:

1 Camshaft and rocker rod lubrication ducts2 Oil vapour cooling labyrinth3 Vent vacuum valve4 Space allowing oil vapour to pass from the cylinder head to the

rocker cover5 Outlet for vapour re-converted into oil by cooling in the labyrinth

with consequent return to the sump6 Outlet to vent oil vapours from the duct to the intake manifold7 Hole to drain oil from the cylinder head8 Oil return from bleed to sump (see description in point 5)9 Seal between rocker cover and cylinder head

The rocker cover seal ensures that the rocker pivot camshaftlubrication circuit is tight. It is therefore advisable to replace itwhenever it is demounted and to remount it with particular care.Damage or breakage of the seal could lead to a pressure drop in thelubrication circuit.Torque the fixing screws to 9 Nm when remounting the cover.

By physical principle, oil vapours reach the cylinder head from thetop part of the engine through hole 4 fig. 38.The moment in which the vapours approach the cover inlet, they areattracted by the vacuum created in the intake manifold (with the aidof valve 3 of fig. 38) with which the cover is in communication (from6 to intake manifold see fig. 39 ).To prevent excessive amounts of oil from reaching the manifoldalong with the vapour in certain extreme conditions (e.g. lack of filtermaintenance, wear on the cylinders, etc.), the venting system hasbeen designed to decant the drops of oil during its passage throughlabyrinth 2 of fig. 38 and to allow them to return to the sump alongthe route ( 5 --> 8 of fig. 39).Vapour that is not re-converted into oil enters intake manifold 6 offig. 39.



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40

42

41

LGW 523 rocker cover

Components :

1 Camshaft and rocker rod lubrication ducts1a Camshaft and rocker rod lubrication routes

2 Rocker cover without labyrinth for oil vapour3 Seal for rocker cover without hole for oil vapour access4 Hole to drain oil from the cylinder head

The rocker cover seal ensures that the rocker pivot camshaftlubrication circuit is tight. It is therefore advisable to replace itwhenever it is demounted and to remount it with particular care.Damage or breakage of the seal could lead to a pressure drop in thelubrication circuit.Torque the fixing screws to 9 Nm when remounting the cover.

LGW 523 bleed

The operating principle of the bleeding system for engine LGW 523is similar to that of engine LGW 627.Vapour and oil are no longer recovered in the rocker cover but in theengine block (cover 3).The oil vapour reaches air filter casing 1 through pipe 2

LGW 523 - LGW 627 valve/rocker clearance

Adjust when the engine is cold: set the pistons of each cylinder tocompression top dead center and adjust the clearance in position Ato 0.20 mm for both the intake and exhaust valves.For greater convenience, clearance adjustment is also accepted inposition B; in this case, the value is 0.15 mm.


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Rocker shaft

Unscrew the nuts from the supports that fix the rocker shaft to thecylinder head. Tighten them to a 40 Nm torque when they areremounted.The shaft is hollow inside to allow for lubrication and is closed at

both ends by two plugs.

Rocker shaft, demounting and refitting

To take the shaft 1 from the support 2, remove pin 3 by drilling it

with a 4 mm bit.On remounting, insert a new pin and recess it in relation to thesurface of support A (0 to 1 mm).Check the shaft (diam. B) and rocker holes (diam. C) for wear.Remove the closing plugs 4 from the ends and thoroughly cleaninside.

Dimensions (mm):

A = 0 to 1.00B = 17.989 to 18.000C = 18.015 to 18.030(C-B ) = 0.015 to 0.041 ( C-B ) wear limit = 0.090

44 45

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Camshaft, demounting

Before removing the camshaft, demount the rocker shaft asindicated in fig. 43Slacken off the screws and remove the cover 1.Make sure that the retention ring 2 is in a perfect condition.

Remove the rod from the fuel pump.Remove the camshaft by pulling and turning, paying particularattention since the cam turns directly on the cylinder block withoutthe aid of bushes.

Note: The eccentric that controls the fuel pump 3 is not an intengralpart of the camshaft, but is faced on to it and fixed with a bolt.Tighten the screw on the eccentric to an 80 Nm torque in caseof replacement.

Camshaft, inspection of pin diameters and housings

Measure the diameters of the housings with a internal comparator

and the camshaft journals with an externalmicrometer.

Camshaft and housings, pin dimensions (mm)

A = 37.035 to 37.060B = 36.975 to 37.000(A-B ) = 0.035 to 0.085 ( A-B ) wear limit = 0.170

Note: The diameters of the camshaft journals and the relativehousings are not the same for all engines in the LGA 523-627series.

Cam height inspection

Use a micrometer for exteriors.

46 47

48 49

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Intake, exhaust cam height

LGW 523A1 = 1st cylinder intakeS1 = 1st cylinder exhaustA2 = 2nd cylinder intake

S2 = 2nd cylinder exhaustH = 30.78 to 30.718 mm (intake and exhaust cam height)

LGW 627A1 = 1st cylinder intakeS1 = 1st cylinder exhaustA2 = 2nd cylinder intakeS2 = 2nd cylinder exhaustH = 30.64 to 30.578 mm (intake and exhaust cam height)

Do not demount or remount while hot as this could lead todeformations.

CYLINDER HEAD, removal

If deformation exceeding 0.10 mm is gauged on the cylinder headsurface, level off by grinding, removing 0.20 mm at most. Consultfig. 82 when tightening the head.

Valves

To remove the valves, first take out the cotters. Place a shim underthe valve mushroom, strongly press on the upper spring plate asshown in the figure.

Components:1 Valve stem2 Oil retainer seal3 Lower spring ring4 Spring5 Upper spring ring6 Cotters

Oil retainer seal in valve guide, removal

To prevent seal 1 from being deformed when the valve guide ismounted, fit it into tool 2 (serial N 7107-1460-047 on page 92) andproceed as shown in the figure, making sure that the seal 1 is fullyinserted.

56 57

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Valve springs

Measure the free length with a gauge.

For LGW 523 - Free length A = 39.8 mm.Replace the spring if the length value is less than 37.3 mm.

For LGW 627 - Free length A = 45.6 mmReplace the spring if the length value is less than 43.1 mm.

Valves, specifications

Exhaust valve A - Stem and mushroom are made of two different

materials.2 Welded section3 Chromium plated section4 Section of material: X 45 Cr Si 8 UNI 3992aaaaa = 4530' to 4545'D = 29.00 mm

Intake valve B - Material: X 45 Cr Si 8 UNI 39921 = Chromium plated sectionaaaaa 1 = 6030' to 6045'C = 33.00 mm

Valve guides and housings

The intake and exhaust guides are both made of grey iron ofphosphorous pearlitic matrix and are dimensionally the same:Dimensions (mm):A = 36.4 to 36.6B = 11.045 to 11.054C = 11.000 to 11.018D = 5.80 to 6.20E = 9.75 to 9.85

Note: Since they are pre-finished, the guides must no longer bemachined after they have been inserted.There are also valve guides with outer diameters B increasedby 0.5 mm.

Valve guides, assembly

Insert the guides with a punch, taking value A into account, inrelation to the head surface.

Dimensions (mm):A = 39.5 to 40.0B = 7.005 to 7.020C = 6.960 to 6.990

Play (mm):(B-C ) = 0.015 to 0.050 ( B- C ) wear limit = 0.10

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Valve seats and housings

Dimensions (mm)A = 34.020 to 34.045B = 34.106 to 34.115C = 30.020 to 30.041

D = 30.108 to 30.116aaaaa = 4453' to 45aaaaa 1 = 5953' to 60Insert the seats in their housings

Note: Since they are pre-finished, the seats must no longer bemachined after insertion.

Valve recessing and width of housing seal.

Dimensions (mm)

D = 0.5 to 0.8 D (wear limit) = 1.1S = 1.6 to 1.7 S (wear limit) = 2.0

Grind the valves in their seats with fine emery paste.After grinding, check the recess of valves D in relation to the headsurface and the retention width of seat S .

Old engine oil can cause skin cancer if repeatedly left in contact

with the skin and for long periods of time. If contact with the oilis unavoidable, you are advised to wash your hands with soapand water as soon as possible.Dispose of old oil in the correct way as it is highly polluting. Donot litter.

Oil sump, removal

Remove the fixing screws.Insert blade 1 into the front and rear main bearing zone to detachthe sump from the engine block.Remove the silicone from the main bearing seals.Apply silicone of the " Dow Corning 7091" type when remounting,as shown in the figure.Tighten the fixing bolts to a 10 Nm torque.

Before starting the engine, make sure that:1) the oil drain plug on the sump has been tightened in the

correct way2) that the right quantity of oil has been added (see pages 13

and 17).

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67 68

Piston

Remove the big-end cap.Remove the piston connecting-rod assembly.

Piston, demounting and inspection

Remove the circlips and take out the pin, see fig. 77.

Take out the piston rings and clean the slots.Measure diameter Q at dimension A from the base of the skirt ( A = 9mm).Replace the piston and piston rings if wear on the diameter exceedsthe minimum given value by more than 0.05 mm.

Note: The forecast allowances are 0.50 and 1.00 mm.

Demounting and remounting the pin stop rings

Remove the circlip by inserting a pointed tool into slot A.When remounting, insert the circlips with their tips pointingdownwards within the angles ( aaaaa = 15 ).

Piston, class and logotypeDepending on their diametral values, the pistons are divided intoclasses: A, B, C. This reference is marked on the crown of the piston,see fig. 71.The logotype is marked inside the piston.Dimensions (mm)

Piston supply:Pistons with nominal value diameters are only supplied in class A.Pistons oversized by 0.50 and 1.00 mm are supplied with a sizereference = 72.5 and = 73 on the crown.


69

70

71

ClassesABC

cylinder 71.990 to 72.00072.000 to 72.01072.010 to 72.020

piston 71.930 to 71.94071.940 to 71.95071.950 to 71.960

play

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Pistons, weight

To prevent imbalance, the pistons must be weighed before they arereplaced.The difference in weight must not exceed 4 g.

Piston rings - Distance between the tips

Fit each piston ring into the cylinder and measure the distance

between tips A in the operating zone.

1st piston ring A = 0.20 to 0.40 wear limit = 1.02nd piston ring A = 0.20 to 0.40 wear limit = 1.03rd piston ring A = 0.20 to 0.45 wear limit = 1.0

Piston rings, play between slots (mm)

A = 0.030 to 0.050B = 0.020 to 0.040C = 0.010 to 0.030

Piston rings, assembly order

A = 1st piston ring (tapering and torsional interior)B = 2nd piston ring (tapering interior)C = 3rd oil scraper piston ringD = Chromium plated zoneE = Chromium plated zone

Note: If there is a caption on the surface of a piston ring, thatsurface should be mounted pointing upwards.

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Lubricate the following parts with oil before mounting: thepiston pin, the piston, the cylinder and the big-end bearing

Piston, refitting

Couple the piston to the connecting-rod by inserting the pin (after it

has been lubricated) and simply pressing with the thumb.Fit in the two circlips that hold the pin in place and make sure thatthey are well housed in their seats; also see fig. 70.Using a piston ring clamp, fit the piston into the cylinder so that theintake valve impression (larger than the exhaust one) on the crown ispointing towards timing system side A.Couple the piston/connecting-rod unit to the crank shaft: consult fig.83 for the head/connecting-rod torque value.

Piston protrusion test

Establish value A of each piston by checking in four differentdiagonally opposite points of the piston crown, then make sure thatthe protrusion does not exceed the following values: 0.95 to 1.27.Series LGW 523-627 has a head gasket with a single thicknessmeasurement (1.65 mm). This means that the clearance can be 0.38min. to 0.70 max..

Only remove the head gasket from its protective wrapping justbefore assembly

Head gasket

The head must not be re-torqued after the running test.

Head torquing

Use a torque wrench with an angular torquing tool, see fig. 81.Measure the length of each bolt (initial free length = 89.5 to 90.5mm). Replace it if it exceeds 92 mm.Lubricate with low viscosity engine oil.

81

77 78

79

80

Measured pistonprotrusion

0.95 to 1.27

Gasket thickness

1.65

Clearance

0.38 min0.38 max


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83

84 85

Once the head has been correctly torqued, it will not need re-torquing unless it is disassembled again.Before mounting, it is advisable to lubricate the bolt shanksand under their heads with SPARTAN SAE 460 oil.

LGW 523-627 head torquing phases

The bolts must be torqued in three phases, in compliance with thenumeric order shown in fig. 82:

1st phase = 50 Nm2nd phase = Turn the torque wrench through 90 in a clockwisedirection.3rd phase = Continue by turning the torque wrench through 90in aclockwise direction.

When remounting the big-end bearings, remember tothoroughly clean the parts and generously lubricate them toprevent seizure when the engine is started up for the first time

Connecting rod (Big-end bearing)

After having uncoupled the connecting-rod from the crank shaft inorder to make the necessary inspections, make sure whenremounting that the two centering marks A and B are on the sameside (see fig. 83).Tighten the big-end cap bolts to a 40 Nm torque.

Note: The big-end bearing is supplied in both the nominal value andundersized by 0.25 and 0.50 mm.

Connecting rod, weight

To prevent imbalance, the connecting rods must be weighed beforethey are replaced.The difference in weight must not exceed 8 grams.The connecting-rods of engines LGW 523 and LGW 627 are madeof cast iron and differ from each other as to length.

Note: For the LGW 523 AUTOMOTIVE version, weigh the pre-assembled connecting rod, piston and pin. The margin oferror must be within 8 grams.


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87 88

Connecting rod complete with bearings and pin

Dimensions (mm)

A = 106.98 to 107.02 (for LGW 523)A = 126.48 to 126.52 (for LGW 627)

B = 18.015 to 18.025C = 40.021 to 40.050 (with bearing torqued to 40 Nm)D = 17.996 to 18.000E = 50.900 to 51.100(B-D) = 0.015 to 0.039 (B-D) wear limit = 0.060

Note: When the small-end bearing is inserted, make sure that thetwo lubrication holes coincide.Lubricate before remounting

Connecting-rod alignment

Use a gauge with surface plate or a comparator as shown in the

figure.Check the alignment of the axes using the piston pin;deviation A = 0.015 mmlimit 0.030 mm.

Small deformations can be corrected under a press, proceeding bygradual movements.



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89 90

91

92

Cylinders

Reset the comparator with a calibrated ring.Check diameter D in points 1, 2 and 3 ; repeat the same operation byturning the comparator through 90at the same levels.Check for possible wear in zone X where the piston rings operate and

grind the cylinder to the next allowance if it exceeds the max. givenlimit (e.g. 72 mm) by 0.05 mm.Dimensions (mm) LGW 523, LGW 627 = 71.990 to 72.000The diametrical values given belong to class A cylinders to whichpistons of the same class must be coupled, see fig. 71.To check the coupling play with the pistons, measure the diameter ofzone Z of each cylinder according to the axis perpendicular to thecrank shaft.

Cylinders, class

The class references of the pistons ( A, B, C, ) are on the piston

crowns while those of the cylinders are on the cylinder block, in theplaces indicated by the arrows (see fig. 91).

Note : For engine LGW 523 with aluminium cylinder block, the castiron cylinders can be normally ground to 0.5 and 1.0 mmallowances.The cylinders must not be replaced.

It is forbidden to touch up the inner surfaces of the cylinderswith emery paper.

Cylinders, roughness

The slant of the crossed honing marks must be between 45 and 55.These marks must be clear and uniform in both directions.The average roughness must be between 0.5 and 1 (micron).The entire surface of the cylinder that comes into contact with thepiston rings must be machined by the faceplate method.

FLYWHEELSIDE

TIMINGSYSTEMSIDE


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94 95

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Central main bearing caps

The central main bearing caps have reference marks that can eitherbe numbers as shown in the figure, or punch marks.The same reference marks are also applied to the cylinder block.Match the caps with the same reference marks and on the same

side. In any case, always refer to the two centering marks on thebush. They must be on the same side.Tighten the screws to a 60 Nm torque.

Before finally torquing and after having torqued, check with aground bar to make sure that planes E-F and G-H arecoplanar

Rear and front main bearing capsWhen remounting rear main bearing cap 1, replace the rubber sideseals 2 remembering that projection A and B from the support mustbe 0.5 to 1.0 mm. Cut off any excess but never ever recess inrelation to the retention surface, only project. Proceed in the sameway for the front main bearing cap.To fit the supports into the cylinder block, insert the two 0.1 mmthick laminations C and D between their surfaces (tool serial N7107-1460-053). Tighten the screws to a 60 Nm torque.Note: It is advisable to apply a few drops of silicone sealer on the

shearing plane of gasket 2.

Checking for play between bearings and main journals

Use calibrated wire A type Perfect Circle Plastigage and apply alittle grease in the center of the bearing. Tighten the screws to a 60Nm torque.Measure the play, checking the extent to which the wire is crushedby means of the relative graduated scale supplied with it in the samepack and available on the market.Consult fig. 107 for the values of the play between main journals,connecting rod pivots and corresponding bearings.

Supporting half-rings

Apply a little grease to make sure that they remain in their housingsduring assembly.The half-rings must be mounted with grooves A as shown in thefigure.Thickness of the half-rings = 2.31 to 2.36 mm; 0.1 and 0.2 mmthickness oversizes are supplied as spares. See further on.


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VIII

99 100

DISASSEMBLY/REASSEMBLY

101 102

Crank shaft float

After having tightened the main bearings, measure float A betweenthe crank shaft support on the flywheel side and the main bearinghalf-rings.

A = 0.130 to 0.313 mm limit 0.5 mmB = 23.05 to 23.10 mm limit 23.50 mm

If the play is not within the given value, check value B . Mountoversized half-rings if necessary. See further on.

Bearing half-rings, oversizes

Dimensions

* A of fig. 99** B of fig. 100

The following half-rings can be mounted by grinding B as shown inthe table:1st Oversize . Half-rings 1 and 2 + 0.10 mm on both sides of

the support.2nd Oversize . Half-rings 1 and 2 + 0.10 mm on one side of the

support and + 0,20 mm on the other.3rd Oversize . Half-rings 1 and 2 + 0.20 mm on both sides of

the support.

The rings could be damaged with ambient temperatures ofless than -35C.

Crank shaft front and rear oil retention seals

Front oil retention seals 1 in the oil pump cover and rear oil retentionseals 2 in the flange on the flywheel side.Replace the seals if they are deformed, hardened or damaged.To replace:

- Thoroughly clean the housing- Keep the seals immersed in engine oil for about half an hour.- Insert it in its housing with a plug, exercising an even pressure all

over its front surface. The two surfaces A and B must be on thesame plane.

- Fill the inner cavity with grease and lubricate the retention lip withthick oil.

Note : Before overhauling the engine and if an oil leak is noted in the retention zone of seals 3 and 4, this fault can berememdied by replacing the seals and pushing the new ones inwards by about 2 mm in relation to the previouslymounted ones.If the seals are black in colour, this means that zones 3 and 4 of the drive shaft are hardened. In this case, remount aseals of the same colour. If the seals are brown, zones 3 and 4 are not hardened and brown coloured seals must bemounted.

103

Standard1st Oversize2nd Oversize3rd Oversize

C22.787-22.92022.987-23.12023.087-23.22023.187-23.320

B**23.050-23.10023.250-23.30023.350-23.40023.450-23.500

0.130-0.313

A*


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104

It is important to wear protective goggles when compressed airis used during repairs

Crank shaft, lubrication ducts

A = Crank shaft LGW 523

B = Crank shaft LGW 627Place the shaft in a bath of degreasing and detergent fluid.Remove the plugs and clean ducts 1 and 2 or 3 and 4 with apointed tool. Blow with compressed air.Fit the plugs back into their housings and check for tightness.

Note: The crank shaft of engine LGW 523 with aluminium cylinderblock cannot be interchanged with that of the cast ironcylinder block since the counterweights are different.

Crank shaft, main journal and crank inspection

Use a micrometer for exteriors.

Diameters of main journal and big-end journals

Dimensions:A = 47.984 to 48.000 wear limit = 47.900B = 39.984 to 40.000 wear limit = 39.900

The diametrical values of the main journal and big-end journals arethe same for all the engines in the series ( LGW 523, LGW 627).

Inner diameters of main and big-end bearings

Dimensions (mm):C = 48.041 to 48.091 wear limit = 48.130D = 40.021 to 40.050 wear limit = 40.100

The given dimensions refer to tightened bearings. Consult fig. 83 forthe big-end tightening torque and fig. 93 for the main bearing captightening torque. Play between bearings and corresponding pivots(mm) see figs. 107, 108.(C-A ) = 0.041 to 0.107 wear limit = 0.230(D-B ) = 0.021 to 0.066 wear limit = 0.130

Note: There are 0.25 and 0.50 mm inner diameter undersizes forboth main and big-end bearings.108

107


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VIII DISASSEMBLY/REASSEMBLY

Hydraulic pump drive (for LGW 627)

A = Third driveA hydraulic pump (2 PD, Bosch flanging or a 1 PD) type can bemounted on the third drive.The power that can be supplied by the third drive is 7 kW,

corresponding to a 37 Nm torque at 3600 rpm.Engine r/min/pump r/min transmission ratio = 1:0.5.

Third drive, components (for LGW 627)

1 Splined sleeve2 Timing pinion3 Retention ring4 Flange for hydraulic pump 1 PD5 Retention ring

Note: Sleeve 1 also includes the fuel pump control eccentric andshould be fixed with the same bolt as the standard eccentricbut with an 80 Nm driving torque. Tighten pinion 2 to thehydraulic pump with a 45 Nm torque.

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110


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LUBRICATION CIRCUIT IX

Components:

1) Pressure switch 6) Oil drain plug 11) Oil pressure regulating screw2) Rocker shaft 7) Oil dipstick 12) Oil pump

3) Big-end journal 8) Breather 13) Crank shaft4) Oil filter cartridge 9) Oil fill plug 14) Oil suction strainer5) Main journal 10) Camshaft

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LUBRICATION CIRCUIT

The engine can be damaged if allowed to operate with insufficient oil. It is also dangerous to add too much oil because itscombustion may lead to a sharp increase in the rotation speed.Use suitable oil in order to protect the engine.Nothing more than lubrication oil can influence the performances and life of an engine.Use of an inferior quality oil or failure to regularly change the oil will increase the risk of piston seizure, will cause the pistonrings to jam and will lead to rapid wear on the cylinder liner, the bearings and all other moving parts. Engine life will also

be notably reduced.The oil viscosity must suit the ambient temperature in which the engine operates.

Old engine oil can cause skin cancer if repeatedly left in contact with the skin and for long periods of time. If contact withthe oil is unavoidable, you are advised to wash your hands with soap and water as soon as possible.Dispose of old oil in the correct way as it is highly polluting.


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LUBRICATION CIRCUITIX

It is important to wear protective goggles when compressed airis used during repairs.Wash the parts with degreasing and detergent liquid.

Internal suction strainer and engine oil return tube

Wash the internal suction strainer 1 and the engine oil return tube 2 ;blow them with compressed air.Replace retention rings 3 and 4 .Tighten the bolts to a 10 Nm torque when the sump is remounted.Tighten the oil drain plug to a 40 Nm torque.

Oil pump

Oil pump flow rate test at 1000 r/min with oil at 80C.

Engine Flow rate (l/min) Pressure(bar) LGW 523 - LGW 627 4 to 4.3 3 to 3.5

Flow rate test at 3600 r/min with oil at 80C

Engine Flow rate (l/min) Pressure(bar) LGW 523 - LGW 627 19.3 4 to 4.5

Oil pump, play between rotors

Measure play A between the teeth as shown in the figure. The maxvalue is 0.171 mm; wear limit play 0.250 mm.Consult figs. 35, 35a and 36 when disassembling and remounting.

Oil pressure regulating valve

Components:1 Valve2 Spring3 Seal4 Plug

Spring length = 27.50 to 27.75 mmBlow the valve housing with compressed air and thoroughly clean allparts before remounting them.

Note : The valve begins to open at a pressure of 4.5 to 5.5 bar at1000 r/min.116

112 113

115

114


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LUBRICATION CIRCUIT IX

When the oil filter is replaced, keep it separate from other waste.Dispose of the old oil correctly since it is highly polluting. Donot litter.

Oil filter cartridge

Components:1 Seal 5 Filtering element2 Plate 6 By-pass valve3 Rubber pad 7 Spring4 Spring

Specifications:Maximum working pressure: 7 barMaximum bursting pressure: 20 barFiltering degree: 15 mBy-pass valve setting: 1.5 to 1.7 barTotal filtering area: 730 cm

Oil pressure check

After remounting, fill up with engine oil, fuel and coolant fluid.Remove the pressure switch, fit on a union and connect a 10 barpressure gauge.Start the engine and watch the pressure variation in relation to theoil temperature.

Note : The pressure of the oil must never be less than 1 bar with amax operating temperature of 80C at 900 r/min.

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X COOLING CIRCUIT

COOLING CIRCUIT

Components :

1) Coolant fill plug 6) Circulation pump2) Compensation chamber 7) Fan3) Thermostatic valve 8) Radiator4) Cylinder block5) Fluid temperature thermoswitch

119

The cooling circuit contains fluid under pressure. Do not carry out any inspections until the engine has cooled and eventhen, open the plug of the radiator or expansion chamber with caution.Keep well away from a hot engine if an electric fan is installed since this could start up even when the engine is at astandstill.

Coolant fluid is polluting. It must therefore be disposed of correctly. Do not litter.


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COOLING CIRCUIT X

Radiator and compensation chamber plug,Inspections and tightness

Remove the plug from the compensation chamber and make surethat the coolant is at the correct level.Replace the plug with one with a connection for a manual air pump.

Compress the air to a pressure of 1 bar for about two minutes.Make sure that there are no leaks from the radiator.The tank plug has a vacuum valve 1 and an overpressure valve 2.Overpressure valve opening pressure 0.7 bar.

Cooling fluid pump, components

1 Impeller

2 Front seal3 Pump casing4 Drain hole5 Bearing6 Pulley7 Shaft

Thermostatic valve

1 - Stainless steel or brass casing2 - Wax bulb3 - Air bleed hole

Specifications:Opening temperature: 83 to 87CMax stroke at 94C = 7 mmFluid flow rate = 30 to 80 l/h.

120

121

122 123


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XI FUELLING CIRCUIT

Do not smoke or use naked flames during the disassemblyand reassembly operations as this could lead to explosions orfire outbreaks.Fuel vapours are highly toxic. Only carry out these operationsoutdoors or in a well ventilated place.Keep your face well away from the cap to avoid inhaling

harmful vapours.Fuelling circuitComponents:1 Tank 6 Pipes from fuel pump to carburetor2 Fuel filter 7 Drain tube from fuel pump to tank3 Fuel pump4 Carburetors5 Tube from tank to fuel filter

Note : The tank complete with filter is supplied on request.Never ever fit the fuel filter near heat sources or naked flames(e.g. silencers, exhaust connection pipes, etc.).Periodically check the condition of the fuel pipes.

Fuel filter detached from tank

The fuel filter for the engines in question is the Lombardini typeserial N3730.106.You are advised to use genuine spare parts since their 350 cmfiltering area volume and their filtering degree have been speciallyresearched.It is advisable to replace the fuel filter after every 350 hours servicein normal operating conditions.When replacing, check the arrow that indicates the correct mountingdirection, see fig. 125.

Fuel pump

Components:1 Fuel pump casing2 Rod3 Retention ring4 Fuel inlet from tank5 Fuel outlet from fuel pump to carburetor6 Fuel pump return to tankThe fuel pump is the diaphragm type and is operated by aneccentric of the camshaft by means of a rod.The eccentric should be tightened to a 80 Nm torque.Specifications:At 2000 r/min of the eccentric, the flow rate is 40 l/h and the self-regulating pressure 0.3 0-05 bar.

Fuel pump rod projection

Projection A of rod 2 from the head surface is 0.85 to 1.35 mm.Inspections must be made with eccentric 1 in the non-operativeposition as shown in figure 127.Lock the two fuel pump fixing nuts to a 24 Nm torque.Check the length of the rod and change it if it is not the right size.Rod length = 85.45 0.5 mm.

127

124

126

125


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Carburetor

Engine LGW 627 is fuelled by two "DELLORTO" carburetors typeFHCD22-18.Comply with the following instructions when adjusting:- The air filter must have a clean cartridge.

- Air must not be drawn through vacuum pipes, seals, etc.- Parts that use electric power must not be operating (electric fans,alternator, etc).

If the carburetors are remounted, tighten the fixing nuts to an 8 Nmtorque and the stud bolts to a 5 Nm torque.

Speed adjuster screw regulation (idling rate)

Use a precision revolution counter.Insert the exhaust gas analyzer probe into the exhaust pipe. Bringthe engine to operating temperature by allowing it to run at about20

work shop manual lgw 523-627 matr 1-5302-509

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