Mercedes-Benz OM 639 / OM 640
The OM 640 is a diesel engine with four cylinders in -line arrangement of Mercedes-Benz . It was installed in the A and B class from 2004 to 2012 . The petrol engine with a similar shape that is most comparable to the OM 640 is the M 266 ; the predecessor was the OM 668 .
technology
The OM 640 has common rail injection and four valves per cylinder. All variants are equipped with engine charging and charge air cooling. As usual with Mercedes, the overhead camshafts are driven by two timing chains .
The engine is inclined approx. 60 ° forwards and is installed transversely behind the driven front axle in vehicles with a sandwich floor . Power is transmitted via a manual gearbox with five (160 CDI) or six gears (180 CDI and 200 CDI) or via the continuously variable Autotronic . The engine and gearbox could only be used in these vehicles due to their unusual installation position.
variants
OM 640
| Engine* | designation | Displacement | Bore · stroke | Compression ratio |
power | Torque | model |
|---|---|---|---|---|---|---|---|
| OM 640 DE 20 LA red. | 640,942 | 1991 cc | 83 x 92 mm | 18: 1 | 60 kW (82 PS) at 4200 rpm | 180 Nm at 1400-2600 rpm | A 160 CDI |
| OM 640 DE 20 LA red. | 640.940 | 1991 cc | 83 x 92 mm | 18: 1 | 80 kW (109 PS) at 4200 rpm | 250 Nm at 1600-2600 rpm | A 180 CDI, B 180 CDI |
| OM 640 DE 20 LA | 640.941 | 1991 cc | 83 x 92 mm | 18: 1 | 103 kW (140 PS) at 4200 rpm | 300 Nm at 1600-3000 rpm | A 200 CDI, B 200 CDI |
Mechanically, the engines are all the same. Due to differences in the engine control and the charging, they achieve different performance values.
OM 639
Based on the OM 640, a variant with a cylinder cap was used in the Smart Forfour and Mitsubishi Colt from 2004 . The OM 639 also has timing chains and common rail injection, with the exception of the missing fourth cylinder, data such as bore and stroke are identical. The installation position is, however, typical in front-wheel drive: Motor standing cross in front of the front axle. It was offered in two performance levels:
| Engine* | Displacement | Bore · stroke | Compression ratio | power | Torque | model |
|---|---|---|---|---|---|---|
| OM 639 DE 15 LA red. | 1493 cc | 83 x 92 mm | 18: 1 | 50 kW (68 PS) at 4000 rpm | 160 Nm at 1600 rpm | for four cdi |
| OM 639 DE 15 LA | 1493 cc | 83 x 92 mm | 18: 1 | 70 kW (95 PS) at 4000 rpm | 210 Nm at 1800 rpm | forfour 1.5 cdi |
* Engine designation is encoded as follows: OM = oil engine (diesel), series = 3 digits, DE = direct injection, displacement = deciliters (rounded), A = exhaust gas turbocharger, L = charge air cooling, red. = reduced power
Others
The predecessor model was the OM 668 engine , from which the Thielert Centurion 1.7 aircraft engine was derived.
The OM 640 model was modified to the Thielert Centurion 2.0 aircraft engine.