Page 1


Preface

This Repair Manual is designed to facilitate competent repair of the engines listed here in. In addition to this Repair Manual the following publications are available: D D D D

Operating Instructions Fuels, Lubricants and Coolants for MAN Diesel Engines Spare-parts catalogue Service record book with maintenance plan

The pictures and relevant descriptions show typical work that may not always be applicable to the engine in hand, which nevertheless does not mean that they are not correct. In such cases the repair work is to be planned and carried out in a similar way. It is compulsory that the engine be removed before performing any of the work describe in this Repair Manual. The expert knowledge necessary for handling Diesel engines was taken for granted when this publication was compiled. Note: Only use fuel, coolants and lubricants in accordance with MAN’s regulations otherwise the manufacturer’s warranty will not apply! For basic information on the fuels see the publication “Fuels, Lubricants and Coolants for MAN Diesel Engines”. You can find the approved products in the internet under: http://www.man-mn.com/ " Products & Solutions " E-Business Any repair of components such as injection pump, alternator etc. ought to be left to our or the manufacturer’s service department.

Best regards MAN Nutzfahrzeuge Aktiengesellschaft Nuremberg Plant

Since our products are in continuous development, we reserve the right to make technical modifications. © 2006 MAN Nutzfahrzeuge Aktiengesellschaft Reprinting, copying or translation, even of extracts, is not allowed without written permission from MAN. All rights under the copyright law are strictly reserved by MAN. MTDB

Technical status: 03.2006

1

51.99598−8166


Instructions

Important instructions which concern technical safety and protection of persons are emphasised as shown below. Danger: This refers to working and operating procedures which must be complied with in order to rule out the risk to persons. Caution: This refers to working and operating procedures which must be complied with in order to prevent damage to or destruction of material. Note: Explanatory descriptions which help in understanding the relevant work or operating procedure to be carried out.

Assembly of pipes Danger: No pipes may be bent. Risk of breakage!

Fitting flat seals / gaskets Flat seals / gaskets are often inserted with sealing agents or adhesives to make fitting them easier or to achieve better sealing. Flat seals may slip in operation due to the “sewing -machine� effect, in particular if they are used between parts with different rates of linear expansion under heat (e.g. aluminium and cast iron), and leaks may then occur. Example: The cap of the front crankshaft seal. If a sealing agent or an adhesive is used here the flat seal will move inwards in the course of time as a result of the different expansion rates of the materials. Oil will be lost, for which the shaft seal may be thought to be responsible.

Flat seals / gaskets can be fitted properly only if the following points are observed: D Use only genuine MAN seals / gaskets D The sealing faces must be undamaged and clean D Do not use any sealing agent or adhesive − as an aid to fitting the seals a little grease can be used if necessary so that the seal will stick to the part to be fitted D Tighten bolts evenly to the specified torque

Fitting round sealing rings D Use only genuine MAN round sealing rings D The sealing faces must be undamaged and clean D Always wet round sealing rings with engine oil before fitting them

2


Contents

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine type classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Safety regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fault table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General notes on engine overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Commissioning after engine overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic diagram of engine lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic diagram of cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic diagram of fuel system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic diagram of engine timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 2 5 6 12 15 16 18 20 21 22 23

Fuel system Removing and installing high-pressure pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing the high-pressure lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing the rail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing the injectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel prefilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing the Fuel Service Centre, replacing the filter cartridge . . . . . . . . . . . . . . . . . .

24 27 28 30 35 36

Cooling system Draining and filling coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing thermostats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing expansion tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing coolant pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Repairing coolant pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cleaning cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing heat exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing pipe cluster for heat exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cleaning heat exchanger pipe cluster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing sea water pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing/installing/stripping seawater pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Changing impeller of sea water pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

38 41 42 43 45 50 52 53 55 56 57 59

Lubrication Changing oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing the oil cooler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing, repairing oil pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing oil injection nozzle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

61 62 64 68

Flywheel / Crankshaft seal Removing and fitting vibration damper, replacing front crankshaft gasket . . . . . . . . . . . . . . . . . . . . . . Removing and installing flywheel, replacing starter gear ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replacing crankshaft seal (flywheel end) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replacing the bearing race . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

69 73 75 76 77

Intake / exhaust system Removing and installing intake pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing exhaust pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turbocharger, troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing turbocharger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Waste gates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing intercooler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

78 79 81 83 85 86

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Contents

Cylinder head Removing and installing cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Setting the valve clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dismantling and assembling the rocker arm mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing valve guides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replacing valve seat insert . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Reworking valve seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refacing valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Checking compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

89 93 94 98 104 105 107 110 111

Valve timing Removing and installing the timing case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing camshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing camshaft bearing bushes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Checking the valve timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

114 116 118 127

Crankgear, pistons Removing and installing crankshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and installing pistons with conrods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing pistons from conrod and fitting, checking − replacing conrod . . . . . . . . . . . . . . . . . . . . . . . Removing and installing piston rings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Replacing cylinder liners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Measuring piston protrusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

128 131 134 136 138 142

Attachments Removing and installing starter motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Removing and attaching alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V-belts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankcase breather (oil separator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

143 144 145 147

Service Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine − Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankcase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder liner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Crankshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Flywheel and starter gear ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conrod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conrod bearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pistons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cylinder head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Valve train . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engine lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cooling system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Turbocharger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuel system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Starter motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Torque guide values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

149 150 151 151 152 154 155 155 156 157 159 162 163 165 166 167 167 168

Special tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

173

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

187

4


Engine type classification

All the engines dealt with here are related in terms of their design and make up a family.

The type classification, which is made up of a series of letters and numbers, reveals some of the features of the engine in question provided the reader is familiar with the underlying nomenclature.

The system is explained below using the model type D 2876 LE 423 as an example: D

The “D” at the start of the type classification stands for “Diesel”

28

The numbers “28” indicates that the power plant in question has a bore of 128 mm

7

The “7” means 166 mm stroke

6

The “6” indicates the number of cylinders 6

L

This letter stands for “charge-air cooling” (German: Ladeluftkühlung)

E

The “E” stands for “fitted engine” (German: Einbaumotor) and is intended to distinguish MAN vehicle engines

423

This is a factory-internal development number

5


Safety regulations

General notes Important safety regulations are summarized in this quick-reference overview and arranged by topic to effectively convey the knowledge necessary to avoid accidents causing injury, damage or environmental hazard. Additional information can be found in the operating instructions of the engine. Important: Should an accident occur despite all precautionary measures, particularly one involving contact with corrosive acid, penetration of fuel under the skin, scalding by hot oil, antifreeze splashing into the eyes etc. you must seek medical assistance immediately.

1. Regulations for the prevention of accidents with personal injury Inspection, adjustment and repair work may only be performed by authorised and skilled personnel. D During installation work, switch off the battery master switch.

D When carrying out maintenance and repair work, ensure that the engine cannot be accidentally started from the bridge by unauthorised persons. D The engine may only be started and operated by authorised personnel. D When the engine is running, do not get too close to the rotating parts. Wear close-fitting working clothes.

D Do not touch hot engine with bare hands: Risk of burns.

D Keep area surrounding engine, ladders and stairways free of oil and grease. Accidents caused by slipping can have serious consequences. D Only work with tools which are in good condition. Worn spanners / wrenches slip: Danger of injury. D Persons must not stand under an engine suspended on a crane hook. Keep lifting gear in order.

D Open the coolant circuit only when the engine has cooled down. If opening the coolant circuit while the engine is hot is unavoidable, observe the instructions in the chapter “Maintenance and care” in the Operator’s Manual. D Do not tighten or undo pipes and hoses under pressure (lubricating oil circuit, coolant circuit and any downstream hydraulic oil circuits). The fluids which flow out can cause injury.

6

ËË ËË


Safety regulations

D When working on the electrical system, first disconnect the earth cable of the battery and reconnect this last to prevent short circuits.

D Follow the manufacturer’s instructions for handling batteries. Caution: Accumulator acid is toxic and caustic. Battery gases are explosive. D When performing welding work, observe the “Notes for welders”.

2. Regulations designed to prevent damage to engine and premature wear D Prior to repairing the engine, clean it thoroughly. Ensure that dirt, sand or foreign matter will not get into the engine during repair work. D If engine operation is disrupted, immediately determine the cause and have it remedied to prevent additional damage. D Always use genuine MAN parts only. Installation of “equally” good parts from other suppliers may cause severe damage for which the workshop carrying out the work is responsible. D Never allow the engine to run dry, i.e. without lubricant or coolant. Appropriate notices must be attached to engines that are not ready for operation. D Today modern components of diesel injection consist of high-precision parts which are exposed to extreme stresses. The high-precision technology requires the utmost cleanliness during all work on the fuel system. Even a particle of dirt over 0.2 mm can lead to the failure of components. D Use only MAN-approved service products (fuel, engine oil, anti-freeze and anti-corrosion agent). Pay attention to cleanliness. Diesel fuel must be free of water. D Do not fill engine oil beyond the max. notch on the dipstick. Do not exceed the maximum permissible tilt of the engine. Serious damage to the engine may result if these instructions are not adhered to. D Control and monitoring devices (charge control, oil pressure, coolant temperature) must be in perfect working order. D Observe the instructions for operating the alternator; see chapter “Maintenance and care” in the Operator’s Manual.

7


Safety regulations

3. Regulations for the prevention of environmental damage Engine oil and filter elements / cartridges, fuel / fuel filter D Old oil must be passed on for recycling. D Take strict precautions to ensure that no oil or Diesel fuel gets into the drains or the ground. Caution: Risk of contamination of potable water. D Filter elements are classed as dangerous waste and must be treated as such. Coolant D Treat undiluted corrosion protection agents and / or antifreeze as hazardous waste. D When disposing of used coolant, the regulations issued by the relevant local authorities must be observed.

4. Notes on safety in handling used engine oil * Prolonged or repeated contact between the skin and any kind of engine oil decreases the skin. Drying, irritation or inflammation of the skin may therefore occur. Used engine oil also contains hazardous substances that have caused skin cancer in tests on animals. If the basic principles of work safety and hygiene are observed, handling used engine oil does not represent a health hazard. Precautionary measures to protect your health: D Avoid prolonged or repeated skin contact with used engine oil. D Protect your skin by means of suitable agents (creams etc.) or wear protective gloves. D Clean skin which has been in contact with engine oil. − Wash thoroughly with soap and water. A nail brush provides effective assistance here. − Special hand cleaning agents make it easier to clean dirty hands. − Do not use petrol (gasoline), diesel fuel, gas oil or solvents as washing agents. D After washing apply a fatty skin cream to the skin. D Change clothing and shoes that are soaked in oil. D Do no put oily cloths in you pockets. Ensure that used engine oil is disposed of in the appropriate manner. − Engine oil is a substance that endangers the water supply − For this reason do not let engine oil get into the ground, waterways, the drains or the sewers. Violations are punishable. Carefully collect and dispose of used engine oil. Information on collection points can be obtained from sales personnel, the supplier or the local authorities. ∗ Based on “Information sheet for handling used engine oil”.

8


Safety regulations

5. Special instructions when working on the common rail system Accident protection D Risk of injury! Fuel jets can cut through skin. The atomisation of fuel creates a fire risk.

− When the engine is running never loosen the screw connections on the fuel’s highpressure side of the common rail system (injection line from the high-pressure pump to the rail, on the rail and on the cylinder head to the injector). − Keep away from the engine when it is running. D Risk of injury! When the engine is running the lines are constantly under a fuel pressure of up to 1600 bar. − Wait at least a minute until the pressure in the rail has dropped before loosening a screw connection. − If necessary check the pressure drop in the rail with MAN-Cats. D Risk of injury! − People with pacemaker must keep at least 20 cm away from the running engine.

− Do not touch live parts on the electric connection of the injectors when the engine is running.

9


Safety regulations

Cleanliness Today modern components of diesel injection consist of high-precision parts which are exposed to extreme stresses. The high-precision technology requires the utmost cleanliness during all work on the fuel system. Even a particle of dirt over 0.2 mm can lead to the failure of components. The measures described as follows are therefore essential before work begins: Risk of damage from penetration of dirt! D Before working on the clean side of the fuel system clean the engine and the engine compartment (high-pressure cleaner). During cleaning the fuel system must be closed.

D Carry out visual inspection for any leakage or damage to the fuel system. D Do not spray the high-pressure cleaner direct onto the electric components, or alternatively keep them covered. D Do not carry out any welding or sanding work in the engine compartment during maintenance / repair. D Avoid air movements (any swirling of dust when starting engines). D The area of the still closed fuel system must be cleaned and dried with the aid of compressed air. D Remove detached particles of dirt such as paint chippings and insulation material with a suitable extractor (industrial type vacuum cleaner). D Cover areas of the engine compartment from which dust particles could be detached with clean foil. D Wash your hands and put on clean work clothes before starting the disassembly work. D Clean tools and working materials before starting to work.

10


Safety regulations

When carrying out the work it is essential to comply with the following measures: Risk of damage from penetration of dirt! D When the clean side of the fuel system has been opened it is not permissible to use compressed air for cleaning. D During assembly work loose dirt must be removed with the aid of suitable extractors (industrial type vacuum cleaners). D Use only fluff-free cleaning cloths on the fuel system. D Only tools without any damage may be used (cracked chrome coatings). D When removing and installing components do not use materials such as cloths, cardboard or wood since these could shed particles and fine fibres. D If any paint chips / flakes off when connections are loosened (from possible over-coating) these chippings must be carefully removed before finally loosening the screw connection. D The connection openings of all removed parts on the clean side of the fuel system are to be closed immediately with suitable caps (see special tools). D These caps / stoppers must be packed protected from dust prior to use and after being used once they must be disposed of. D Following this all the components must be carefully stored in a clean, closed container. D Never use used cleaning or testing liquids for these components. D New parts must not be removed from their original packing material until directly before use. D Work on removed components may be carried out only at a workplace specially equipped for it. D If removed parts are shipped always use the original packing material of the new part.

11


Fault table

Operating faults and possible causes We recommend A repair is only complete when both the damage that occurred and the possible causes have been eliminated. Finding out the cause of damage is often more difficult than repairing the damage that occurred. We therefore recommend that you obtain a precise description of the operating fault before removing and dismantling components. Then use a process elimination (questions) to pin-point the probable causes and investigate and eliminate these successively on the basis of the table and your own experience. This helps to reduce repairs to the required scale and to counteract claims regarding “over-eager” replacement of parts and complaints about expensive work and down time.

Note: The following list is conceived as an aid to memory for experts so that to causes of damage are overlooked when dealing with faults. The precondition for this, however, is that the experts are familiar with the Repair Manual for the engine as well as the accompanying Operating Instructions and the publication “Fuels, Lubricants and Coolants for MAN Diesel Engines”.

12


Fault table

1. 2.

EDC self-diagnosis or flash code output Starter motor turns over engine slowly or not at all 3. Starter motor turns, engine fails to start, engine fails to start / difficult to start when cold 4. Engine stalls (dies) during operation, no longer starts (starter motor turns), engine fails to start / difficult to start when hot 5. 6.

x x x x x

Sudden, temporary engine shutdown, engine does not reach full revs Engine runs at idle speed only, no throttle response 7. Engine runs at increased idle speed only, no throttle response 8. Rated engine speed significantly reduced (even at no load) 9. Reduced power output in all ranges 10. Irregular engine operation, loss of traction 11. Unstable idle speed, engine surges, misfiring, engine knocking 12. Engine judder 13. Unusual combustion noises 14. Excessive smoke emission: white smoke / blue smoke 15. Excessive smoke emission: black smoke 16. Engine temperature too high (coolant loss) 17. Fuel consumption too high 18. Lubrication oil pressure too low 19. Lube oil pressure too high 20. Lube oil consumption too high 21. Engine too “loud” / mechanical noises 22. Idle speed cannot be adjusted with idle speed operating unit Possible causes Battery flat, battery lead connections loose or corroded, break in power circuit Crankshaft drive blocked Starter solenoid switch sticks (clicks) / damaged, cable connection loose or damaged

x x

Starter motor / starter interlock relay defective (carbon brushes worked loose / worn, winding damaged, short to ground)

x

x x x

Engine oil viscosity unsuitable, not suitable for ambient temperature, lube oil quality does not comply with specifications

x

Oil level in oil pan too high Oil level in pan too low, oil in oil pan too thin (mixed with condensate or fuel) Engine temperature too high Oil filter clogged Oil pressure gauge defective Safety valve in the oil circuit defective (does not close, spring fatigued or broken) Heavy bearing wear Oil pump gears heavily worn Timing gears worn, tooth flank backlash too great Engine cold Lube oil entering combustion chamber (piston rings worn, piston rings broken) − valve stem guide worn − overpressure in crankcase (crankcase breather clogged) Safety valve in oil circuit defective (does not open), oil lines / oil galleries clogged Leaks in lube oil circuit, particularly at turbocharger and oil cooler Piston rings heavily worn, broken Piston pins or crankshaft bearings loose Valve stems heavily worn, bent Valve clearance not correct Valves jammed Compression deficient, or more than 3−4 bar pressure difference between individual cylinders

x x x x x x x x x

x x

x

x x

x

x x x

x x

x x

x x x x

x

x o

x

x

x x

x x

x = o =

x x x

x

x x x x

x x

x x x

x x x

x x

x

x

x

x

x

Valve seats leaking Increased power input due to defective secondary loads / consumers such as hydraulic pumps, fan etc., power take-off engaged x

Air filter fouled or clogged, charge air system leaking, air intake / exhaust lines clogged / leaking Fuel low pressure system: Fuel tank, prefilter, water trap faulty / clogged / mould / fungal attack, fuel unsuitable / contaminated (paraffin added) Fuel low pressure system: fuel lines leaking, broken, clogged

likely to apply might apply

13


Fault table

1. 2.

EDC self-diagnosis or flash code output Starter motor turns over engine slowly or not at all 3. Starter motor turns, engine fails to start, engine fails to start / difficult to start when cold 4. Engine stalls (dies) during operation, no longer starts (starter motor turns), engine fails to start / difficult to start when hot 5.

Sudden, temporary engine shutdown, engine does not reach full revs Engine runs at idle speed only, no throttle response 7. Engine runs at increased idle speed only, no throttle response 8. Rated engine speed significantly reduced (even at no load) 9. Reduced power output in all ranges 10. Irregular engine operation, loss of traction 11. Unstable idle speed, engine surges, misfiring, engine knocking 12. Engine judder 13. Unusual combustion noises 14. Excessive smoke emission: white smoke / blue smoke 15. Excessive smoke emission: black smoke 16. Engine temperature too high (coolant loss) 17. Fuel consumption too high 18. Lubrication oil pressure too low 19. Lube oil pressure too high 20. Lube oil consumption too high 21. Engine too “loud� / mechanical noises 22. Idle speed cannot be adjusted with idle speed operating unit Possible causes x x x x x x x Fuel low pressure system: Air in system (turn on ignition when bleeding system) x x x x x x x x x Fuel low pressure system: Feed pump, main filter x x x x x o x x Fuel high pressure system: Injectors defective / clogged / leaking / coked x x x x o Fuel high pressure system: pressure lines − constriction, cavitation, leaking x x o x x x x o Fuel high pressure system: High-pressure pump worn x x x x o Pedal value sensor (driving lever signal) defective: connection lines, short circuit, interruption 6.

x x x x

x x

x o o o

x x x o

EDC rpm sensor defective, lead defective EDC rpm sensor, polarity reversed EDC detects incorrect engine speed (interference signal on rpm sensor lead) EDC boost pressure sensor: faulty, incorrect, implausible with atmospheric pressure sensor, line fault

o

x

x

x

x

o x x x

x x o

o

x x x x x

o

x x x x x x x

x x x

x x o o o o x

o x x x

o o

o x

x x

x x

x = o =

x

Exhaust turbocharger leaking or defective Turbine and compressor wheel in the turbocharger soiled (running off balance) Intercooler leaking, defective EDC coolant temperature sensor: faulty, line fault EDC charge-air temperature sensor: faulty, line fault Radiator fouled or failure of cooling system (temperatures too high) Coolant level too low, air in the coolant circuit V-belt for coolant pump drive not tensioned correctly Incorrect V-belt tension Coolant pump leaking, defective / thermostat defective, does not open Coolant lines leaking, blocked or twisted Coolant entering combustion chamber (cylinder head / gasket leaking) Power supply to EDC control unit interrupted or battery voltage too low EDC control unit defective (internal fault) Incorrect EDC control unit (check MAN part number) Afterrunning not completed Thermostat defective Engine bearings worn

likely to apply might apply

14


General notes on engine overhaul

The service life of an engine is influenced by very different factors. It is therefore not possible to specify certain fixed numbers of operating hours for general overhauls. In our view, it is not necessary to open up an engine or perform a general overhaul as long as the engine has good compression values and the following operating values have not changed significantly in relation to the values measured on commissioning the engine: D Charging pressure D Exhaust temperature D Coolant and lubricant temperature D Oil pressure and oil consumption D Smoke emissions The following criteria greatly influence the length of the engine service life: D Correct power output setting according to the type of application D Technically correct installation D Inspection if installation by authorised personnel D Regular maintenance as per maintenance plan D Choice and quality of lube oil, fuel and coolant in accordance with the publication “Fuels, Lubricants and Coolants for MAN Diesel Engines�

15


Commissioning after engine overhaul

Pressurisation It is extremely important for internal combustion engines (following the completion of repair work, i.e. in their dry state) to be pressurised with lube oil before being recommissioned. This procedure can also be used for ascertaining damage and its causes. If engines are not pressurised, the risk of premature damage to bearing surfaces is very high because it takes a relatively long period of time for the lube oil drawn in from the oil pan via the oil pump to reach the individual bearings. Such incipient damage need not necessarily lead to immediate bearing failure, but may impair the proper functioning of the bearings and reduce their service lives.

Diagram of the oil flow with unpressurised engines

16


Commissioning after engine overhaul

Pressurising an engine affords the following advantages: D All engine parts are lubricated before engine startup; a lubricating film can be built up inside the bearings as early as after the first few rotations of the crankshaft, thereby preventing damage to the bearing races D Any loss of oil, be it the result of excessively large bearing play or leaks from the crankcase or from crankcase bores which may not be plugged, can be detected immediately. For this purpose, mount the engine on an assembly dolly, remove the oil pan and install a suitable oil collector under the crankcase in such a way that the bearings are visible

Performance of pressurisation: At least 30% of the total oil quantity is forced from the pressurisation container into the engine oil circuit. The operating pressure serves as the yardstick for the pressure to be forced in and must not be exceeded. The pressurisation container is connected up to the engine oil circuit at the oil filter (screw plug).

17


Engine views D 2876 LE 423

1

2

3

4

5 6

5 7

11

10

9

8

12

13

14

16

15

18


Engine views D 2876 LE 423

À Exhaust turbocharger Á Crankcase breather valve  Relief valve on coolant surge tank à Heat exchanger and coolant surge tank Ä Alternator Å Coolant pump Æ Engine cranking device Ç Oil cooler housing È Oil filter É Hand vane pump 11

Fuse box

12

Oil filler neck

13

Fuel-Service-Center

14

Fuse box

15

Hand priming pump

16

Sea water pump

19


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Man marine diesel engines r6 730 series service repair manual  
Man marine diesel engines r6 730 series service repair manual  
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