The Mercedes OM605 engine is a 5-cylinder pre-chamber diesel engine equipped with an ERE control system (Electronische Reihen Einspritzpumpe). This 2.5-liter engine was assembled from 1993 to 2001 and was installed on several very popular models of the concern, such as W124, W202, W210. It was offered in an atmospheric version with 113 hp and a turbocharged version with 150 hp.
The diesel R5-family includes: OM617, OM602, OM605, OM612, OM647.
Specifications
| Production years | 1993-2001 |
| Displacement, cc | 2497 |
| Fuel system | prechamber |
| Power output, hp | 113 (OM 605 D 25 or 250 D) 150 (OM 605 D 25 LA or 250 TD) |
| Torque output, Nm | 170 (OM 605 D 25 or 250 D) 280 (OM 605 D 25 LA or 250 TD) |
| Cylinder block | cast iron R5 |
| Block head | aluminum 20v |
| Cylinder bore, mm | 87 |
| Piston stroke, mm | 84 |
| Compression ratio | 22.0 |
| Features | no |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | no |
| Turbocharging | no (OM 605 D 25 or 250 D) yes (OM 605 D 25 LA or 250 TD) |
| Recommended engine oil | 5W-40 |
| Engine oil capacity, liter | 6.5 |
| Fuel type | diesel |
| Euro standards | EURO 2/3 |
| Fuel consumption, L/100 km (for Mercedes C250 TD 1999) — city — highway — combined |
9.4 5.3 7.3 |
| Engine lifespan, km | ~400 000 |
| Weight, kg | 215 |
The engine was installed on:
- Mercedes C-Class W202 in 1993 – 2001;
- Mercedes E-Class W124 in 1993 – 1996; E-Class W210 in 1995 – 1999.
Disadvantages of the OM605 engine
- Increased vibrations in the operation of the motor negatively affect the resource of its supports;
- The timing chain does not last very long, it can stretch on a run of 200 thousand km;
- This diesel is afraid of overheating, from which the aluminum cylinder head can simply burst;
- Shrinking quick couplers contribute to the airing of the fuel system;
- Hydraulic lifters often fail due to the use of low-quality oil.
Benefits of OM605
- reliability – low-power cast iron motor, the piston group does not experience heavy loads and, as a result, easily withstands up to 1 million km with proper maintenance;
- a minimum of electronics – the lack of a large number of electronics and computers contributes to harmonious work;
- economical compared to gasoline engines.
