|OM651: new generation of four-cylinder diesel engines. Click to enlarge.|
New engines and new transmissions in the Vito and Viano reduce emissions and fuel consumption by up to 15% while enhancing performance. All engines comply with the Euro 5 emissions standard. In addition to the new ECO Gear six-speed manual transmission, the BlueEFFICIENCY technology with ECO start/stop which comes as standard is an option.
|The revamped Vito as a panel van. Click to enlarge.|
All diesel engines are equipped with an oxidation catalytic converter, a particulate filter and cooled exhaust gas recirculation. The new ECO Gear manual transmission offers a broad gear ratio spread for optimum performance and enables low fuel consumption and emission levels. The Vito is the only model in its class to feature a six-speed transmission for all four-cylinder drive variants as standard, Mercedes says.
Four-cylinder CDI. At the core of the new generation of engines is the four-cylinder in-line unit which has the internal code OM 651. It is available in three power variants for the Mercedes-Benz Vito:
|Vito Four-Cylinder CDI Variants|
|Vito 110 CDI||Vito 113 CDI||Vito 116 CDI|
|Figures differ according to variant|
|Power output||70 kW (95 hp) at 3800 rpm||100 kW (136 hp) at 3800 rpm||120 kW (163 hp) at 3800 rpm|
|Max torque||250 Nm at 1200-2400 rpm||310 Nm at 1400-2600 rpm||360 Nm at 1600-2400 rpm|
|Fuel cons. (NEDC)||7.7 L/100 km
(BlueEFFICIENCY 7.4 L/100 km)
|7.4 L/100 km
(BlueEFFICIENCY 6.9 L/100 km)
|7.4 L/100 km
(BlueEFFICIENCY 6.9 L/100 km)
(BlueEFFICIENCY 195 g/km)
(BlueEFFICIENCY 182 g/km)
(BlueEFFICIENCY 182 g/km)
|Top speed||158 km/h||176 km/h||191 km/h|
|18.1 s||13.4 s||11.5 s|
This represents an overall rise in power output and torque in comparison to the predecessor models, with major increases in some instances. At the same time, fuel consumption and CO2 emissions have been reduced by up to 15%, depending on the engine variant.
The high torque of the long-stroke engine with 83 mm bore and a stroke of 99 mm provides for unusually high tractive power. The two overhead camshafts actuate a total of 16 inlet and exhaust valves via cam followers with hydraulic valve clearance compensation.
The camshafts are driven via a combination of gearwheels and a short chain, providing the robust basis for a virtually endless service life, according to Mercedes. This is especially advantageous in tough commercial use involving high mileage and high levels of stress and strain.
Fuel injection takes place by means of a common rail system. Particularly durable solenoid valves and seven-hole injection nozzles provide for extremely precise fuel injection with up to five injections per combustion cycle. The benefits of this technology include a gentle build-up of pressure and a smooth-running engine. The maximum injection pressure is 1800 bar.
Charging is carried out by a turbocharger with variable turbine geometry which combines high efficiency with swift response to movements of the accelerator pedal. Maximum torque is available right from very low engine speeds and over a broad rev range—another key benefit in commercial operations requiring high tractive power. With its combination of a rated engine speed of 3800 rpm and elasticity, the four-cylinder engine has an unusually broad useful operating range between around 1000 and 4000 revs. This is unmatched by any other diesel engine in this class of vehicle, Mercedes says.
Common rail injection, the low-vibration forged crankshaft running on five bearings and the rear camshaft drive provide the foundation for the engine’s surprisingly smooth running. All four-cylinder engines also benefit from Lanchester balancing, with two counter-rotating shafts running under the crankcase, driven by spur gears. Mercedes-Benz is the only manufacturer in this vehicle class to deploy balancer shafts in all four-cylinder engines of its vans.
Demand-responsive auxiliary units. The development engineers have also devoted great attention to optimizing the auxiliary units. The oil pump is a controlled vane-type pump featuring electrical actuation, for example. It controls its delivery rate automatically according to the given requirements, as does the controlled fuel pump. This reduces the power output, thereby lowering fuel consumption. The coolant pump also adjusts automatically to the given requirements, further helping to reduce fuel consumption. The same goes for battery management, with the alternator charging only when necessary.
ECO Gear six-speed manual transmission. The new six-speed ECO Gear manual transmission comes as standard for all Vito models equipped with a four-cylinder diesel engine. This transmission is a substantial contributory factor to the reduced fuel consumption and further enhanced dynamic performance of the Vito CDI. Its defining feature is a particularly broad gear ratio spread, with a short first gear (i=5.076) and a long sixth gear (i=0.675) designed to keep the engine speed low.
This configuration accords due consideration both to typical situations such as hill starts with full payload and loaded trailer and to long journeys on the motorway. Overall, the engine speed has been reduced substantially in the interests of lower fuel consumption and emissions. Another consequence of this strategy is a noticeable improvement in ride comfort.
The well-proven five-speed automatic transmission is alternatively available for the Vito. It comes as standard for the Vito 122 CDI and Vito 126.
The V6. The V6 engine in the Vito 122 CDI is based on an aluminium crankcase with a V angle of 72 degrees. Thanks to offset connecting rod journals, the engine runs more smoothly than any other diesel in its class, Mercedes says. The technical highlights include a total of four chain-driven overhead camshafts, common rail injection with piezo injectors and eight injection holes per injector for ultra-fine atomization of the fuel.
The latest version of the engine in the Vito 122 CDI offers 10% percent more power, at 165 kW (224 hp) and an unchanged level of torque, at 440 Nm. It complies with the Euro 5 emissions standard. At the same time, fuel consumption and CO2 emissions have fallen by around 5%. Other enhancements of this latest version of the V6 include a maximum injection pressure of 1600 bar.
Vito 126. The Vito 126 features a V6 gasoline engine, also Euro5 compliant and coupled with an automatic transmission.
BlueEFFICIENCY. BlueEFFICIENCY technology is available as an option for the Vito panel van and comes as standard in the Vito crewbus licensed as a passenger car. A label below the A-pillar confirms that BlueEFFICIENCY is on board. The scope of the package includes:
- ECO start/stop function (not for automatic transmissions);
- Battery management;
- Minimum Rolling Resistance tires;
- ECO power steering pump;
- Shift point indicator (not for automatic transmissions)
- A controlled fuel pump; and
- Internal engine measures.
The BlueEFFICIENCY package further reduces the Vito’ consumption by an additional 0.2-0.3 liters per 100 km (6.75 g of CO2 per km) in the new generation, according to model and engine variant.
The Viano offers two engine variants based on the OM 651:
|Viano Four-Cylinder CDI Variants|
|Viano CDI 2.0 CDI||Viano CDI 2.2|
|Power output||100 kW (136 hp) at 3800 rpm||120 kW (163 hp) at 3800 rpm|
|Max torque||310 Nm at 1400-2600 rpm||360 Nm at 1600-2400 rpm|
|Fuel cons. (NEDC)||7.24 L/100 km||7.24 L/100 km|
|CO2||190 g/km||190 g/km|
|Top speed||174 km/h||188 km/h|
|14.1 s||12.18 s|
The new ECO Gear six-speed manual transmission comes as standard for the Viano CDI 2.0 and CDI 2.2.
The latest version of the engine in the Viano CDI 3.0 offers 10% more power, at 165 kW (224 hp), and 440 Nm of torque. Fuel consumption and CO2 emissions have fallen by around 5%. Other enhancements of this latest version of the V6 include a maximum injection pressure of 1800 bar.