OM 602
The successor of the OM617 engine family was the newly developed straight-5 Diesel automobile engine OM602 from Mercedes-Benz used from 1980s up to 2002. With some Mercedes-Benz 250D/E250D diesels exceeding 500,000 or 1,000,000 miles, it's considered to be the one of the most reliable engines ever produced, a success which is only comparable with the famous OM617 engine.
The 5-cylinder OM602 was succeeded by the four valve engine OM605 (E250D 20V) and later the OM612 and OM647 with turbo charger and Common Rail Direct Injection (C/E/ML 270CDI).
The engine
The Mercedes OM602 engine is a 5 cylinder diesel engine of 2497cc. The engine was also increased in capacity to 2874cc (2.9L) and used in the Phase 1 Mercedes Sprinter vans, the Ssangyong Musso and Korando range and even in the 1996-1999 models of the E-class. It was available in either naturally aspirated or turbocharged variants with two valves per cylinder.
The camshafts and injection pump are driven by duplex chain from the crankshaft. A separate single row chain drives the oil pump. The camshaft operated the valves via hydraulic bucket tappets; valve clearance adjustment is automatic.
On earlier models of 2497cc Fuel injection is indirect. A Bosch PES in-line injection pump is used, with a mechanical governor and vacuum-operated stop control. The pump is lubricated by a connection to the engine oil circulation and the fuel lift pump is mounted on the side of the injection pump.
The later, 2.9L capacity unit uses a Bosch VE style rotary distributor injection pump with electronic control. This larger capacity version uses direct injection.
Preheating is by glow plugs with automatic control of preheating time.
Versions of OM602 Mercedes 5-cylinder diesel engine
| Model indication | Year | Engine no OM602... | Power in kW (HP) |
| OM 602.xxx (5-cylinder diesel) | |||
| W201 190 2.5 D & W124 250 D | 04/1985 - 06/1993 | .911 & .912 & .930 & .931 | 66 (90) (<'89) or 69 (94) (>'89) |
| G-Class 250 GD 4x4 | .938 & .939 | ||
| 210 & 310 & 410 2,9 D. | 10/1988 -> ? | .940 & .942 | 72 (98) or 75 (102) |
| G-Class 290 GD 4x4 | .946 & .947 | ||
| W201 190 2.5 turbodiesel & W124 250D Turbo | 01/1987 -> 1993 | A.961 & A.962 | 90 (122) (<'88) or 92 (126) (>'88) |
| Sprinter 2,5 Turbo-D. | A.963 | ||
| 212D & 312D & 412D & Sprinter 2,9 TD. | 02/1995 -> 04/2000 | A.980 & A.986 | 90 (122) |
| G-Class 290 GD turbodiesel 4x4 | 07/1997 -> 09/2000 | A.983 | 88 (120) |
| W210 E290 turbodiesel | 03/1996 -> 07/1999 | A.982 | 95 (129) |