宝马E65培训资料s(11).pdf

?NOTEThe information contained in this training course manual is intended solely forparticipants of the BMW Service Training course.Refer to the relevant Technical Service information for any changes/supplements to the Technical Data.2001 BMW AGMnchen,Germany.Reprints of this manual or its partsrequire the written approval of BMW AG,MnchenVS-42 MFP-HGK-BRK-N62_0300ContentsPageCHAP 1Introduction1History1Future2The Valvetronic principle4Introduction of the N62 engine6-Technical data7-Full load graphs8-N62B36 engine view10CHAP 2Engine mechanics12General air intake system12Air ducts13-Fresh air system13-Throttle valve14-Variable intake pipe15-Crankcase venting system18Exhaust system19-Exhaust manifold with catalytic converter20-Silencer20-Secondary air system21Auxiliary components and belt drive22-Belt drive22-Alternator23-Coolant compressor26-Starter motor27-Power steering pump27Cylinder heads28-Introduction28-Cylinder head covers31-Valve gear33Bi-VANOS(variable camshaft adjustment)35-VANOS function36-Timing diagram39Valvetronic40-Description of the function40-Valve lift adjustment components42-Valvetronic adjustment diagram45-Chain drive46Cooling system50-Coolant circuit50-Water pump54-Map-controlled thermostat54-Cooling module55-Cooling radiator56-Coolant expansion tank56-Transmission oil-water heat exchanger(WT)57-Electrically operated fans57-Viscous coupling fan57Engine block58-Oil sump58-Crankcase59-Crankshaft60-Connecting rod and piston62-Flywheel63-Vibration damper63-Engine suspension63Lubrication system64-Oil circuit64-Oil pump66-Oil filter67-Oil cooling67-Technical data68CHAP 3N62 engine management system ME9.269-General information69-Overview70-Functional description73-Oxygen sensor regulation74-Emission control75-Oil level/condition77-Variable intake manifold80-Valvetronic81-Idle speed control83CHAP 4N62 fuel system84Mixture control84-General information84-Injection valves84-Fuel pressure regulator85-Electric fuel pump(EKP)85-EKP regulation86Tank system87-General information89-Fuel tank leak diagnostic module(DMTL)90N62 NG engine-1-IntroductionHistoryThe petrol and diesel engines used today are highly technicalassemblies.With the introduction of and further developments in directinjection,the diesel engine in particular has achievedperformance values which had previously only been achieved byvery good petrol engines.It has also been possible to significantly reduce fuelconsumption.In the past,petrol engines were able to achieve very goodtorque and performance levels,and it was possible to reducefuel consumption by 10%.In addition,the lowest emissionsvalues were achieved.Note the measures introduced in order to achieve these objec-tives:Notes_Nevertheless,in the meantime,a noticeable gap has developedin terms of fuel consumption between the petrol engine and thediesel engine.Innovations such as direct injection and throttle-free load controlwith variable valve train,however,suggest such great potentialfor petrol engines that the petrol engine can approach the part-load fuel consumption values of the diesel engine.N62 NG engine-2-FutureThe following market and legal requirements drive our plans forthe future:-Reduced fuel consumption-Improved performance-Increased comfort-Reduced emissions-Improved cost/benefit ratioReferred to the engine,improvements in fuel consumption meanan increase in efficiency.There are three technically feasibleoptions for increasing efficiency:-Increasing the engines efficiency byNotes_-Reducing losses caused by frictionNotes_-Avoiding charge cycle losses byNotes_N62 NG engine-3-Of these three options,avoiding charge cycle losses presentsthe greatest potential for improvement and,in principle,can beused on any throttle-controlled engine.Throttle-free load control offers the potential for a reduction infuel consumption comparable to that of the direct injectionpetrol engine,theoretically without any discernible weak points.At BMW,the variable valve train,in conjunction with DoubleVanos,is known as Valvetronic.The Valvetronic system facilitates improved consumptionwithout the disadvantages of direct injection in terms ofemissions.Notes_VANOSValvetronicPetrol-DI(direct injection)High pressure efficiency+Charge cycle worko+Emission characteristic+-Full load+(+)+=very good;+=good;o=normal;-=poorN62 NG engine-4-The Valvetronic principleThe Valvetronic principle can be compared to the behaviour ofthe human body when placed under physical strain.Imagine youare jogging.The amount of air the body takes in is regulated bythe lungs.You breathe in deeply and the lungs supply the air thebody needs for energy conversion.If you stop jogging and starta more gentle form of exercise,for example walking,the bodyrequires less energy and therefore less air.The lungs adjust tothis automatically by taking more shallow breaths.If you were tohold a towel in front of your mouth in this scenario,if would bemuch harder to breathe.If we look at this in terms of Valvetronic system fresh air intake,the throttle valve(towel)is missing.The valve lift(lungs)isregulated in accordance with the air requirement.The enginecan aspirate freely.The PV diagram below offers a technical explanation.Fig.1:Charge cycle diagram comparison-left without Valvetronic,right withValvetronicIndexDescriptionIndexDescriptionPPressureAExhaust valve opensOTTop dead centreASExhaust valve closesUTBottom dead centreZIgnition timingEIntake valve opens1Work outputESIntake valve closes2Compression outputGainLossLossGainKT-6299KT-6298N62 NG engine-5-The upper area marked Gain represents the power accumu-lated as the fuel burns.The lower area marked Loss representsthe pumping work.This is the energy that must be applied inorder to expel the combusted exhaust gases from the cylinderand to draw the fresh gases into the cylinder.The throttle valve is almost always opened far enough during theValvetronic motor intake procedure that a vacuum of just 50mbar is set.Load control is based on the moment the valvecloses.Compared with a standard engine with load control viathe throttle valve,the vacuum created in the inlet manifold issmall,meaning that less energy is required to create thevacuum.The improved efficiency is achieved by the lower power lossduring the intake operation.In the previous diagram,the conventional procedure with theslightly greater loss is shown on the left.The reduced loss can be clearly seen in the right-hand diagram.Unlike the diesel engine,in the case of the conventional petrolengine,the volume of intake air is controlled by means of theaccelerator pedal and the throttle valve and the correspondingvolume of fuel is injected in the stoichiometric ratio(=1).On engines with the Valvetronic system,the volume of intake airis determined by the opening lift and the opening duration of thevalves.The precisely supplied fuel quantity means that =1operation is realised here too.A petrol engine with direct injection and stratified charge in wideload ranges,on the other hand,is operated on a leaner fuel-airmixture.This means that more expensive emissions treatment which ismore susceptible to sulphur,such as that for direct injectionpetrol engines,is not necessary on engines with Valvetronic.Notes_N62 NG engine-6-Introduction of the N62 engineThe N62 engine is a completely new development from theNG(New Generation)series and is available in two enginecapacity versions,B36=3.6 l and B44=4.4 l.In the future,it will replace the M62 engine.The objectives are:-A significant reduction in fuel consumption-A reduction in the emission of pollutants-Increased power-Improved torque-Improved torque curve-Improved engine acousticsIn order to achieve these objectives,a complete package ofmeasures was introduced in the following areas:-Engine mechanics-Valve timing-Intake air guidance-Subsequent treatment of exhaust emissions-Engine management controlThe most important features of the new N62 engine are basedon-8-cylinders in V configuration-90 cylinder configuration-2 four-valve cylinder heads-light-alloy design-newly-developed variable intake manifold-ValvetronicN62 NG engine-7-Technical dataEngineN62B36N62B44Design8 cylinder V8 cylinder VV angle9090Displacement(cm3)36004398Bore/stroke(mm)84/81.292/82.7Cylinder gap(mm)9898Main crankshaft bearing diameter(mm)7070Crankshaft connecting rod bearing diameter(mm)5454Output(kW)at engine speed(rpm)20060002456000Torque(Nm)at speed(rpm)36033004503100Cut-off speed(rpm)65006500Compression ratio10.210.0Valves/cylinders44Intake valve diameter(mm)3235Exhaust valve diameter(mm)2929Intake valve lift(mm)0.3-9.850.3-9.85Exhaust valve lift(mm)9.79.7Cams opening period(crankshaft)282/254282/254Engine weight(kg)(construction group 11 to 13)213213Fuel rating(RON)9898Fuel(RON)91-9891-98Firing sequence1-5-4-8-6-3-7-21-5-4-8-6-3-7-2Knock controlYesYesVariable intake manifoldYesYesDigital motor electronicsME9.2+Valvetroniccontrol unitME9.2+Valvetroniccontrol unitConforms with exhaust emission regulationsEU-3EU-4LEVEU-3EU-4LEVEngine length(mm)704704Fuel consumption saving compared with the M6213%14%Vmax(km/h)E65 electronic cut-out250250N62 NG engine-8-Full load graphsN62B36Fig.2:Full load graphs comparison.Dashed line=M62B35Output in kWTorque in NmEngine speedKT-8235N62 NG engine-9-N62B44Fig.3:Full load graphs comparison.Dashed line=M62B44Output in kWTorque in NmEngine speedKT-8236N62 NG engine-10-N62B36 engine viewFig.4:N62 engine front viewIndexDescription1Valvetronic motors2Tank ventilation valve(AKF valve)3VANOS solenoid valve4Alternator5Pulley for the water pump6Thermostat housing7Throttle unit8Vacuum pump9Intake pipe to air cleanerKT-7886N62 NG engine-11-Fig.5:N62 engine rear viewIndexDescription1Camshaft position sensor,cylinder bank 5-82Valvetronic eccentric shaft position sensor,position sensor 5-83Valvetronic eccentric shaft position sensor,position sensor 1-44Camshaft position sensor,cylinder bank 1-45Secondary air valves6Servomotor for variable intake manifoldKT-7681N62 NG engine-12-Engine mechanicsGeneral air intake systemEngine output and engine torque increases,as well as optimi-sation of the engine torque curve are largely dependent on anoptimum engine volumetric efficiency over the entire enginespeed range.Good volumetric efficiency in the lower and upper speed rangesis achieved via long and short intake paths.Long air intake pathsensure good volumetric efficiency in the lower to middle speedranges.This optimises the torque curve and increases the torque.In order to achieve a power increase in the upper speed range,the engine requires short air intake paths for better filling.The air intake system has been completely reworked in order toeliminate this inconsistency in terms of air intake path length.The air intake system consists of the following components:-Intake air ducts upstream of the air cleaner-Air cleaner-Intake pipe with HFM(hot-film air-mass flow sensor)-Throttle unit-Variable intake manifold-Intake portN62 NG engine-13-Air ducts-Fresh air systemFig.6:N62 air routingThe intake passes through the air intake ducts from the aircleaner to the throttle section in the variable intake manifold,and on to the two cylinder head intake ducts.In accordance with fording depth guidelines,the air intake ductsare situated high in the engine compartment.Fording depth is asfollows:-150 mm water depth at 30 km/h-300 mm water depth at 14 km/h-450 mm water depth at 7 km/hThe air cleaner element is designed to be changed at100,000 km intervals.IndexDescription1Air intake duct2Air cleaner housing with intake air silencer3Intake pipe with HFM(hot-film air-mass flow sensor)4Secondary air valves5Secondary air pumpKT-7888N62 NG engine-14-Throttle valveThe throttle valve mounted on the N62 is not necessary forengine load control.This is carried out by the intake valvesvariable lift adjustment.The tasks of the throttle valve are:-To provide support for and optimal engine start-To ensure a constant 50 mbar vacuum in the intake pipe in allload ranges.Notes_N62 NG engine-15-Variable intake pipeFig.7:Variable intake manifold housingThe intake manifold is located in the V of the engine,and ismounted on the cylinder head intake ducts.The variable intake manifold housing is made from a magnesiumalloy.Notes_IndexDescription1Drive unit2Thread for engine cover3Crankcase venting system connection4Tank ventilation connection5Intake air6Injection valve holes7Fuel rail threadKT-6799N62 NG engine-16-Fig.8:Interior view of the variable intake manifoldEach cylinder has its own intake pipe(1)which is connected tothe manifold volume(6)via a rotor(3).The rotors are supported by one shaft(4)per cylinder bank.The shaft for the cylinder bank 1-4 rotors is adjusted by a driveunit,an electric motor with speed-transforming transmission,depending on the engine speed.The second shaft,from which the rotor for the opposite cylinderbank is adjusted,is turned by the driven shaft active throughspur gears(5)in the opposite direction.The intake air flows via the manifold volume through thefunnel(2)and on to the cylinders.The intake path length is setas the rotor turns.The drive motor is controlled by the DME and is intended forproviding feedback about the funnel position via a potenti-ometer.IndexDescription1Intake port2Funnel3Rotor4Shaft5Spur gears6Manifold volumeKT-6800N62 NG engine-17-Fig.9:Intake manifold set to short intake pathFig.10:Intake manifold set to longer intake pathThe intake path length can be adjusted according to the enginespeed.Adjustment from long to short intake path begins at3,500 rpm.As the engine speed increases,the intake pathlength is reduced linearly,up to 6,200 rpm.KT-8114KT-8115N62 NG engine-18-Crankcase venting systemFig.11:Cylinder head cover with labyrinth trapThe crankcase vapours(blow-by gases)produced duringcombustion are carried from the crankcase and into the cylinderhead cover via a labyrinth trap.The oil which accumulates on the walls of the labyrinthseparator flows into the cylinder head via a siphon,and fromthere flows back to the sump.The remaining gases are passedback to the engine for combustion via the pressure controlvalve(5)in the intake manifold.One labyrinth trap with pressure control valve is integrated ineach of the two cylinder head covers.The throttle valve is controlled such that there is always anegative pressure of 50 mbar in the intake manifold to draw offthe gases.The pressure control valve regulates the crankcase pressure to alow 0-30 mbar.IndexDescription1-4Openings for spark plugs5Pressure control valve6Opening for Valvetronic motor7Opening for Valvetronic sensor connector8Camshaft sensorKT-7711N62 NG engine-19-Exhaust systemFig.12:Exhaust systemThe exhaust system was completely redesigned for the N62B36and N62B44 engines,and is identical in each engine.It hasbeen optimised in terms of cylinder filling and scavenging,theacoustic system and rapid catalytic converter light-off.Notes_IndexDescriptionIndexDescription1Manifolds with integratedcatalytic converter5Centre silencer2Broadband oxygen sensors6Exhaust flap