Between 1985 and 2001, a number of diesel engines, including the Mercedes OM 602 for 2.5 and 2.9 liters, were assembled and fitted to numerous well-known models of the company, including the W124, W201, W210, and W463. Apart from the engine’s pre-chamber versions, a direct fuel injection version was also available.
The diesel R5-family comprises OM617, OM602, OM605, OM612, and OM647.
Specifications
| Production years | 1985-2001 |
| Displacement, cc | 2497 (OM 602 D 25 or 250D, OM 602 D 25 A or 250TD) 2874 (OM 602 D 29 or 290D, OM 602 DE 29 LA or 290TD) |
| Fuel system | prechamber |
| Power output, hp | 84 – 94 (D25) 122 – 126 (D25A) 95 – 98 (D29) 120 – 129 (DE29LA) |
| Torque output, Nm | 154 – 158 (D25) 225 – 231 (D25A) 192 (D29) 280 – 300 (DE29LA) |
| Cylinder block | cast iron R5 |
| Block head | aluminum 10v |
| Cylinder bore, mm | 87 (D25, D25A) 89 (D29, DE29LA) |
| Piston stroke, mm | 84 (D25, D25A) 92.4 (D29, DE29LA) |
| Compression ratio | 22.0 (D25, D25A, D29) 19.5 (DE29LA) |
| Features | no (D25, D25A, D29) intercooler (DE29LA) |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | no |
| Turbocharging | no (D25) yes (D25A) no (D29) yes (DE29LA) |
| Recommended engine oil | 5W-40 |
| Engine oil capacity, liter | 7.0 |
| Fuel type | diesel |
| Euro standards | EURO 1 |
| Fuel consumption, L/100 km (for Mercedes 190D 1992) — city — highway — combined |
8.6 5.5 7.1 |
| Engine lifespan, km | ~450 000 |
| Weight, kg | 205 |
The engine was installed on:
- Mercedes C-Class W201 in 1985 – 1993;
- Mercedes E-Class W124 in 1985 – 1996; E-Class W210 in 1996 – 1999;
- Mercedes G-Class W460 in 1987 – 1992; G-Class W461 in 1992 – 2001; G-Class W463 in 1990 – 1992;
- Mercedes TN/T1 VAN in 1989 – 1995;
- Mercedes T1N Sprinter W901 in 1997 – 2000.
Disadvantages of the OM602 engine
This diesel engine’s strong vibrations have a negative impact on the supports’ lifespan.
The block head cracks when the timing chain breaks, which lasts between 200 and 250 thousand kilometers.
Antifreeze that is inexpensive or outdated frequently ruptures the cylinder head gasket.
Hydraulic lifters can run up to 90,000 kilometers on low-quality oil.
Additionally, the vacuum injection pump control system is a major source of issues for the owners.
Modifications OM602
The most famous modifications:
- The power unit 912 has a 2497 cubic meter working volume. It generates 94 horsepower. Each cylinder has two valves.
- 911: same displacement but more power (90 horsepower) Each cylinder has four valves.
- 962: a turbine-equipped engine with two valves per cylinder that has the same displacement but already produces 126 horsepower.
Features of additional modifications:
| 602.911 | 2497 cc, Power 90 hp (66 kW) Australia, USA, Japan |
| 602.911 602.912 602.930 |
2497 cc, Power 94 hp (69 kW) |
| 602.931 | 2497 cc, Power 84 hp (62 kW) |
| 602.938 602.939 |
2497 cc, Power 94 hp (69 kW) For Gelaendewagen, onboard network 24V. |
| 602.940 | 2874 cc, Power 95 hp (70 kW) |
| 602.941 | 2874 cc, Power 88 hp (65 kW) |
| 602.942 | 2874 cc, Power 98 hp (72 kW) |
| 602.946 | 2874 cc, Power 95 hp (70 kW) |
| 602.947 | 2874 cc, Power 98 hp (72 kW) For Gelaendewagen, onboard network 24V. |
| 602.948 | 2874 cc, Power 97 hp (71 kW) For Gelaendewagen, onboard network 24V. OM 602 D29 |
| 602.961 | 2497 cc, Power 122 hp (90 kW) turbocharged. OM 602 A. USA, Japan |
| 602.961 602.962 |
2497 cc, Power 126 hp (93 kW) turbocharged. OM 602 A |
| 602.962 | 2497 cc, Power 122 hp (90 kW) turbocharged. OM 602 A. USA, Japan |
| 602.980 | 2874 cc, Power 122 hp (90 kW) turbocharged. OM 602 DE LA |
| 602.981 | 2874 cc, Power 122 hp (90 kW) turbocharged. OM 602A DE 29 LA |
| 602.982 | 2874 cc, Power 129 hp (95 kW) turbocharged. OM 602 DE LA |
| 602.983 602.984 602.985 602.986 |
2874 cc, Power 122 hp (90 kW) turbocharged. OM 602A DE LA |
| 602.990 | 63 kW (86 hp) |
| 602.994 | 72 kW (98 hp) |