4-cylinder injection engine (natural gas)

Chapter overview

• Technical data
  1
• 1 Safety instructions
  1
• 1.1 Safety precautions during work on fuel system
  1
• 1.2 Safety precautions when working on vehicles with a gas system
  1
• 1.4 Safety precautions when working on cooling system
  4
• 1.5 Safety precautions when working on ignition system
  5
• 2 Identification
  6
• 2.1 Engine number, engine data
  6
• 3 Repair instructions
  7
• 3.1 Rules for cleanliness
  7
• 3.2 Foreign objects in engine
  7
• 3.3 Contact corrosion
  7
• 3.4 Routing and securing lines
  7
• 3.5 Installing coolers, condensers and radiators
  8
• Removing and installing engine
  9
• 1 Removing and installing engine
  9
• 1.1 Removing engine
  10
• 1.2 Securing engine on engine and gearbox support
  14
• 1.3 Installing engine
  15
• 2 Assembly mountings
  19
• 2.1 Assembly overview - assembly mountings
  19
• 2.2 Supporting engine in installation position
  19
• Crankshaft group
  22
• 1 Cylinder block (pulley end)
  22
• 1.1 Assembly overview - poly V-belt drive
  22
• 1.2 Removing and installing poly V-belt
  23
• 2 Sealing flanges and flywheel
  25
• 2.1 Assembly overview – sealing flanges
  25
• 2.2 Removing and installing crankshaft sealing flange on gearbox side
  26
• 2.3 Renewing crankshaft oil seal - belt pulley end
  27
• 2.4 Removing and installing sealing flange on pulley end
  31
• 3 Cylinder block and add-on parts
  36
• 3.1 Assembly overview - cylinder block
  36
• 4 Crankshaft
  38
• 4.1 Assembly overview - crankshaft
  38
• 4.2 Crankshaft dimensions
  40
• 5 Pistons and conrods
  41
• 5.1 Assembly overview - pistons and conrods
  41
• 5.2 Checking pistons, piston rings and cylinder bores
  43
• 5.3 Piston and cylinder dimensions
  45
• Cylinder head, valve gear
  46
• 1 Cylinder head
  46
• 1.1 Assembly overview - cylinder head
  46
• 1.2 Removing and installing cylinder head
  47
• 1.3 Checking compression
  55
• 2 Toothed belt drive
  57
• 2.1 Assembly overview - toothed belt
  57
• 2.2 Removing, installing and tensioning toothed belt
  58
• 2.3 Checking semi-automatic toothed belt tensioner
  65
• 3 Valve gear
  66
• 3.1 Assembly overview - valve gear
  66
• 3.2 Renewing camshaft oil seal
  68
• 3.3 Removing and installing camshaft
  71
• 3.4 Removing and installing valve stem seals
  73
• 4 Inlet and exhaust valves
  77
• 4.1 Checking valve guides
  77
• 4.2 Renewing valve guides
  77
• 4.3 Reworking valve seats
  78
• 4.4 Valve dimensions
  80
• Lubrication
  81
• 1 Sump, oil pump
  81
• 1.1 Assembly overview - sump and oil pump
  81
• 1.2 Engine oil
  82
• 1.3 Removing and installing oil sump
  83
• 1.4 Removing and installing oil pump
  85
• 2 Oil filter, oil pressure switch
  87
• 2.1 Assembly overview - oil filter housing, oil pressure switch
  87
• 2.2 Checking oil pressure and oil pressure switch
  88
• Cooling
  91
• 1 Cooling system, coolant
  91
• 1.1 Coolant hose schematic diagram
  91
• 1.2 Checking cooling system for leaks
  92
• 1.3 Draining and filling coolant
  94
• 2 Coolant pump, regulation of cooling system
  98
• 2.1 Assembly overview - coolant pump, thermostat
  98
• 2.2 Removing and installing coolant pump
  99
• 2.3 Removing and installing thermostat
  101
• 3 Radiator and radiator fan
  105
• 3.1 Assembly overview - radiator and radiator fan
  105
• 3.2 Removing and installing radiator
  106
• 3.3 Removing and installing radiator fan V7 and radiator fan 2 V177
  108
• Mixture preparation - injection
  110
• 1 Injection system
  110
• 1.1 Installation location overview - injection system
  110
• 1.2 Bleeding fuel system
  113
• 2 Injectors
  117
• 2.1 Assembly overview - fuel rail with injectors
  117
• 2.2 Checking injectors for leaks and quantity injected
  118
• 2.3 Checking fuel pressure regulator and holding pressure
  122
• 2.4 Removing and installing injectors
  126
• 3 Checking natural gas supply system for leaks
  128
• 3.1 Different pressure sections of natural gas supply system
  128
• 3.2 Determining pressure in gas system
  131
• 3.3 Determining operating mode of natural gas vehicles
  131
• 3.4 Activating/deactivating natural gas mode
  132
• 3.5 Checking gas system for leaks
  133
• 4 Gas injectors
  139
• 4.1 Assembly overview - gas rail with gas injectors
  139
• 4.2 Removing and installing gas rail with gas injectors
  140
• 5 Gas pressure regulator
  142
• 5.1 Removing and installing high-pressure valve for gas mode N372
  142
• 5.2 Removing and installing tank pressure sensor G400
  144
• 6 Air filter
  147
• 6.1 Assembly overview - air filter housing
  147
• 7 Intake manifold
  148
• 7.1 Assembly overview - intake manifold
  148
• 7.2 Removing and installing upper part of intake manifold
  149
• 7.3 Removing, installing and dismantling lower part of intake manifold
  152
• 8 Engine control unit
  154
• 8.1 Removing and installing engine control unit J623
  154
• 8.2 Removing and installing engine control unit J623 with protective housing
  155
• Exhaust system
  158
• 1 Exhaust pipes, silencers
  158
• 1.1 Assembly overview - silencers
  158
• 2 Emission control
  159
• 2.1 Assembly overview - emission control
  159
• 2.2 Removing and installing catalytic converter
  160
• Ignition system
  162
• 1 Ignition system
  162
• 1.1 General notes on ignition system
  162
• 1.2 Assembly overview - ignition system
  162
• 1.3 Test data, spark plugs
  164