1、Introduction of the New Inline Engine Generation 4-Cylinder M 274Introduction into Service ManualDaimler AG, GSP/OI, HPC R 822, D-70546 StuttgartOrder no.: 6516 1390 02 HLI0000000791 - Printed in Germany 03/12 This printout will not be recorded by the update service. Status: 03 / 2012 Mercedes-Benz
2、ServiceIntroduction of the New Inline Engine Generation4-Cylinder M 274Daimler AG Technical Information and Workshop Equipment (GSP/OI) D-70546 Stuttgart This printout will not be recorded by the update service. Status: 03 / 2012 Information and copyright This printout Product PortfolioComprehensive
3、 information about our full Product Portfolio can also be found at our Internet Portal. Link: http:/aftersales.mercedes-Questions and suggestionsIf you have any questions or suggestions concerning this product, please write to us. Email: Fax: +49-(0)18 05/0 10-79 78 2012 by Daimler AGThis document,
4、 including all its parts, is protected by copyright. Any further processing or use requires the previous written consent of Daimler AG, Department GSP/OIS, HPC R822, W002, D-70546 Stuttgart. This applies in particular to reproduction, distribution, alteration, translation, microfilming and storage a
5、nd/or processing in electronic systems, including databases and online services.Image no. of title image: P00.01-4267-00 Image no. of poster: P00.01-4268-00 Order no. of this publication: 6516 1390 02 HLI000000079103/12will not be recorded by the update service. Status: 03 / 2012 ContentsPreface 5Ov
6、erviewBrief description 6Engine views 8Engine data comparison with predecessor engine 14Engine data 15CO2 measures 16 Mechanical componentsCrankcase 18Oil pan 20Crank assembly 21Cylinder head 22Belt drive 23Chain drive and camshaft adjustment 24 CombustionAir supply 26Vacuum system 27Charging 28Inje
7、ction system 32Fuel system 38Exhaust system 423bIntroduction of the New 4-Cylinder Inline Engine Generation, M 274 This printout will not be recorded by the update service. Status: 03 / 2012 4ContentsCooling and lubricationEngine cooling 46Engine lubrication 52 Electrical and electronic systemsEngin
8、e control 54Ignition system 58On-Board Diagnosis 60 AnnexAbbreviations 62Contents 63b Introduction of the New 4-Cylinder Inline Engine Generation, M 274 This printout will not be recorded by the update service. Status: 03 / 2012 Preface5bIntroduction of the New 4-Cylinder Inline Engine Generation, M
9、 274Dear Reader,This Introduction into Service Manual presents the new 4-cylinder gasoline engine 274 in model series 204.The purpose of this brochure is to acquaint you with the technical highlights of this new engine generation in advance of its market launch. This brochure is intended to provide
10、information for people employed in service or maintenance/repair as well as for after-sales staff. It is assumed here that the reader is already familiar with the Mercedes-Benz engines currently on the market.This Introduction into Service Manual is not intended as an aid for repairs or for the diag
11、nosis of technical problems. For such needs, more extensive information is available in the Workshop Information System (WIS) and Xentry Diagnostics.WIS is updated continuously. Therefore, the informa-tion available there reflects the latest technical status of our vehicles and major assemblies.This
12、 Introduction into Service manual presents initial information relating to the new engine generation and, as such, is not stored in WIS. The contents of this brochure are not updated. No provision is made for supplements.We will publicize modifications and new features in the relevant WIS documents.
13、 The information presented in this Introduction into Service Manual may therefore differ from the more up-to-date information found in WIS.All information relating to technical data is valid as of the copy deadline in January 2012 and may therefore differ from the current production configuration.Da
14、imler AGTechnical Information and Workshop Equipment (GSP/OI) This printout will not be recorded by the update service. Status: 03 / 2012 6OverviewBrief descriptionIn June 2012, the new M 274 4-cylinder gasoline engine with direct injection and turbocharging will be introduced for the first time wit
15、h the modification year of model series 204.The M 274 forms an engine family together with the transverse-mounted M 270 engine model series installed in model series 246. It is available in model series 204 as a 1.6 l displace-ment variant with 115 kW.This new engine family replaces the very success
16、ful major assemblies of engine model series M 271 EVO.The new direct injection system combines an extremely fast and accurate injector with a new, spray-guided combustion system. The M 274 engine model series fulfills the increasingly strict CO2limits while also providing high torque, engine power a
17、nd particularly comfortable noise and vibration characteristics. The use of flexible technology modules has made it possible to reduce consumption and untreated emis-sions. They allow varying worldwide market-specific and legal requirements to be fulfilled as well as ensuring the future of the engin
18、e family.Supplementing the technology portfolio is a coolant thermal management system to regulate the coolant circuit during the warm-up phase. The regulated vane-type oil pump with map-controlled two-stage control pressure allows the lubrication and cooling points in the engine to be supplied with
19、 a significantly lower operating energy input than would be possible with an unregulated pump. Compared to the predecessor M 271 EVO, a lower engine weight and lower friction power contribute to energy efficiency. This is supplemented by controlled ancillaries and the standard ECO start/stop functio
20、n.Introduction of the New 4-Cylinder Inline Engine Generation, M 274b This printout will not be recorded by the update service. Status: 03 / 2012 OverviewBrief descriptionAn overview of the special features of the M 274: Gasoline direct injection with piezo injectors of the latest generation for the
21、 spray-guided Mercedes-Benz combustion system Fast action piezo injectors for multiple fuel injection Combination of direct injection with turbocharging Boost pressure control via vacuum Advanced camshaft adjusters for optimized engine timing Further developed regulation and optimization of oil and
22、cooling circuit with a regulated engine oil pump and coolant pump ECO start/stop function with starter-assisted direct starting Demand-controlled multi-spark ignition Crankcase made of diecast aluminium Fulfillment of EU 5 emissions standard with potential to fulfill future standardsP01.10-3126-00M
23、274 in model series 204 with 115 kW from 1.6 l displacement7Introduction of the New 4-Cylinder Inline Engine Generation, M 274 b This printout will not be recorded by the update service. Status: 03 / 2012 8OverviewEngine viewsP01.10-3102-00View of engine from front1 Air filter housing50/3 Noise damp
24、erA9 Refrigerant compressorB17/12 Charge air temperature sensor upstream of throttle valveB28/6 Pressure sensor upstream of throttle valveG2 AlternatorR39/2 Wide open throttle operation vent line heater elementY101 Bypass air switchover valveIntroduction of the New 4-Cylinder Inline Engine Generatio
25、n, M 274b This printout will not be recorded by the update service. Status: 03 / 2012 OverviewEngine viewsP01.10-3103-00View of engine from rear11 Vacuum pump19 High-pressure pumpB28/5 Pressure sensor downstream of air filterY94 Quantity control valve9Introduction of the New 4-Cylinder Inline Engine
26、 Generation, M 274 b This printout will not be recorded by the update service. Status: 03 / 2012 10OverviewEngine viewsP01.10-3104-00View of engine from right158 Three-way catalytic converterB70 Crankshaft Hall sensor (with rotation direction detection)G3/1 Oxygen sensor downstream of catalytic conv
27、erterG3/2 Oxygen sensor upstream of catalytic converterT1/1 Cylinder 1 ignition coilT1/2 Cylinder 2 ignition coilT1/3 Cylinder 3 ignition coilT1/4 Cylinder 4 ignition coilIntroduction of the New 4-Cylinder Inline Engine Generation, M 274b This printout will not be recorded by the update service. Sta
28、tus: 03 / 2012 OverviewEngine viewsP01.10-3105-00View of engine from leftA16/1 Rear knock sensorA16/4 Front knock sensorB11/4 Coolant temperature sensorB28/6 Pressure sensor upstream of throttle valveM1 StarterM16/6 Throttle valve actuatorR48 Coolant thermostat heating elementY58/2 Partial load oper
29、ation crankcase ventilation system valve11Introduction of the New 4-Cylinder Inline Engine Generation, M 274 b This printout will not be recorded by the update service. Status: 03 / 2012 12OverviewEngine viewsP01.10-3106-00View of engine from above50 Turbocharger50/2 Boost pressure control flap vacu
30、um unitB4/25 Fuel pressure and temperature sensorB6/15 Intake camshaft Hall sensorB6/16 Exhaust camshaft Hall sensorB17/13 Charge air temperature sensor downstream of throttle valveB28/7 Pressure sensor downstream of throttle valveN3/10 ME-SFI ME control unit (motor electronics)Y31/5 Boost pressure
31、control pressure transducerY49/1 Intake camshaft solenoidY49/2 Exhaust camshaft solenoidY76/1 Cylinder 1 fuel injectorY76/2 Cylinder 2 fuel injectorY76/3 Cylinder 3 fuel injectorY76/4 Cylinder 4 fuel injectorY133 Coolant pump switchover valveIntroduction of the New 4-Cylinder Inline Engine Generatio
32、n, M 274b This printout will not be recorded by the update service. Status: 03 / 2012 OverviewEngine viewsP01.10-3107-00Engine view from belowS43 Oil level check switch Y130 Engine oil pump valve13Introduction of the New 4-Cylinder Inline Engine Generation, M 274 b This printout will not be recorded
33、 by the update service. Status: 03 / 2012 14OverviewEngine data comparison with predecessor engineBR 204 C 180 CGIAs of 09/2009C 180As of 06/2012Engine designation M 271 EVO M 274Engine model desig-nation271.820 274.910Displacement cm31796 1595Rated output kW at rpm11550001155300Rated torque Nm at r
34、pm2501600 43002501250 4000Compression ratio 9.8 : 1 10.3 : 1Emissions standard EU 5Engine configuration/ no. of cylindersInline 4Valves 4Air supply Turbocharger with charge air coolingBoost pressure controlVia boost pressure Via vacuumBoost pressure bar 1.2 1.1Bore mm 82.0 83.0Stroke mm 85.0 73.7Cyl
35、inder spacing mm 90.0Connecting rod lengthmm 143.5 152.2Injection Direct injection (DI)Introduction of the New 4-Cylinder Inline Engine Generation, M 274b This printout will not be recorded by the update service. Status: 03 / 2012 OverviewEngine dataP01.00-3356-00Torque and power curve of M 27415Int
36、roduction of the New 4-Cylinder Inline Engine Generation, M 274 b This printout will not be recorded by the update service. Status: 03 / 2012 16OverviewCO2 measuresThermal managementThe thermal management function controlled by the ME-SFI ME control unit regulates the coolant temper-ature in the eng
37、ine. It allows the operating tempera-ture to be reached more quickly, which reduces exhaust emissions and improves heating comfort. Post-start phaseIn the post-start phase, the ME-SFI ME control unit transmits a signal to the coolant pump switchover valve. This is then shut off.By interrupting the c
38、oolant circulation, the engine heats up more quickly, which reduces exhaust emis-sions. Coolant thermostat heatingThe temperature of the coolant in the engine can be varied via the heated thermostat. There is a heating element in the thermostat. The heating element is actuated by the ME-SFI ME contr
39、ol unit via a ground signal and adjusts the posi-tions of a rotary ball valve as required via the expanding wax element.Fan controlThe ME-SFI ME control unit actuates the fan motor. The target fan speed is specified by the ME-SFI ME control unit by means of a pulse width modulated signal (PWM signal
40、).The on/off ratio of the PWM signal is between 10% and 90%.For example:10 % fan motor “OFF“20 % fan motor “ON“, minimum rpm90 % fan motor “ON“, maximum rpm If the actuation is faulty, the fan motor turns at the maximum speed (fan limp-home mode).The automatic air conditioning control and operating
41、unit transmits the status of the air conditioning to the ME-SFI ME control unit via the interior CAN and chassis CAN. Delayed fan switch-offAfter “ignition OFF“ the fan motor runs on for up to 5 min if the coolant temperature or the engine oil temperature have exceeded the specified maximum values.T
42、he on/off ratio of the PWM signal during run-on is max. 40%. If the battery voltage drops too much during this time, the delayed fan switch-off is suppressed.Introduction of the New 4-Cylinder Inline Engine Generation, M 274b This printout will not be recorded by the update service. Status: 03 / 201
43、2 OverviewCO2 measuresRadiator shuttersIn combination with engine 274, the C-Class features adjustable radiator shutters which allow the air flow through the cooling module and engine compartment to be controlled. The radial slats of the radiator shutters are located in front of the fan wheel across
44、 its circumference and are integrated in the fan shroud. The slats are opened and closed by an actuator attached to the cooling module. Closing the radiator shutters reduces aerodynamic drag and thus fuel consumption. In addition, this prevents the engine compartment from cooling down and dampens th
45、e external noise produced by the engine.The radiator shutters actuator is actuated by the ME-SFI ME control unit after the engine is started by means of a ground signal. A vacuum is thus built up in the vacuum unit and the radiator shutters are closed by the actuator and associated linkage.One parti
46、cular advantage of adjustable radiator shut-ters is the positive influence they have on aerody-namics and the associated potential to reduce fuel consumption. Furthermore, when the adjustable radiator shutters are closed they allow: The operating temperature to be reached more quickly An increase in
47、 heating comfort A further reduction in engine noise Overheating protectionThe overheating protection function protects against engine damage due to thermal overload and against damage to the catalytic converter caused by over-heating.If the coolant temperature or charge air temperature is too high,
48、 the ignition timing is adjusted in direction “Retarded“ depending on the engine speed and load. The correction in direction “Retarded“ is controlled by the ME-SFI ME control unit based on a performance map.Adjustment of the ignition timing starts at a coolant temperature of approx. 90 C and a charg
49、e air temper-ature of approx. 20 C.The adjustment of the ignition timing in direction “Retarded“ corresponds to e.g.:2 CKA at 100 C coolant, 20 C charge air and wide open throttle 8 CKA at 100 C coolant, 60 C charge air and wide open throttle 11 CKA at 125 C coolant, 60 C charge air and wide open throttle In addition, the ME-SFI ME control unit actuates the coolant thermostat heating element to fully open the thermostat so that all the coolant is cooled vi
