Characteristics of the M104 engine
The M104 engine from Mercedes-Benz was produced at the Stuttgart-Bad Cannstatt Plant from 1992 to 1998. This six-cylinder in-line engine found use in various Mercedes-Benz models including the C 280 W202, 280 E / E 280 W124, E 280 W210, 300 SE W140, S 280 W140 and SL 280 R129. Thanks to its reliability and high performance, the M104 has become one of the brand’s iconic engines.
Structure and Materials
The main material of the cylinder block of the M104 engine is cast iron, which ensures high strength and durability. The engine features an injectorized power system, which promotes precise fuel injection and improves overall efficiency. The M104 has an inline configuration with six cylinders, each with four valves for improved cylinder fill and power.
Piston stroke is 73.5 mm and cylinder diameter is 89.9 mm. The engine had two main modifications with compression ratios of 9.2 and 10, providing different power and torque characteristics.
Performance and Economy
For the 2,799 cc displacement modification, the engine develops 193 horsepower at 5,500 rpm and 270 Nm of torque at 3,750 rpm. In the other version, the power output is 197 horsepower at 5800 rpm and torque is 265 Nm at 3000 rpm. These characteristics provide the cars with excellent dynamic performance and smooth ride.
The engine is designed to use 95 octane fuel. Fuel consumption for the E280 W124 with this engine is 14.5 liters per 100 km in the city cycle, 11.0 liters on the highway and 12.5 liters in mixed mode. Oil consumption can reach up to 1000 grams per 1000 km, which is the norm for powerful engines of the time.
Maintenance and Service Life
A variety of viscosity oils are recommended for the M104 engine including 0W-30, 0W-40, 5W-30, 5W-40, 5W-50, 10W-40, 10W-50, 15W-40 and 15W-50. The full volume of oil in the engine is 7.5 liters, about 7.0 liters is filled when changing. The recommended oil change interval is 7000-10000 km to maintain optimum engine performance. The operating temperature of the engine is about 90 degrees Celsius.
According to the factory data, the exact engine life is not specified, but in practice, the M104 engine demonstrates a resource exceeding 400 thousand kilometers, which indicates its high reliability and durability.
Tuning and Potential
The M104 engine has significant tuning potential, allowing you to increase power to 600 or more horsepower. This makes it an attractive choice for car enthusiasts and professionals looking to improve the performance of their vehicles without significantly sacrificing engine life.
The M104 engine from Mercedes-Benz is an example of the combination of high technology and engineering excellence. Its reliability, durability and high potential for tuning make it one of the best engines of its time. Installed on various Mercedes-Benz models, it has provided them with excellent dynamic performance and reliable operation over the years.
Reliability, problems and repair of the Mercedes M104 E28 2.8 engine
The lowest-volume engine in the M104 series (which also included the M104 E30, M104 E32, M104 E34 and M104 E36) was developed on the basis of the M104 E32 to replace the previous M103 E26. A new crankshaft was installed in the 3.2-liter cylinder block, with a piston stroke of 73.5 mm, instead of 84 mm on the base motor. The cylinder head is similar to the M104 E32 with a variable intake timing system. The fuel injection system is distributed injection. The intake manifold with variable geometry.
The timing system uses a reliable two-row chain.
The engine was in production until 1998, after which it was replaced by the M112 E28, with V6 configuration.
M 104 E 28 engine modifications
- M104.941 (1993 – 1997) – version rated at 193 hp at 5500 rpm, 270 Nm of torque at 3750 rpm. It was installed on Mercedes-Benz C 280 W202.
- M104.942 (1992 – 1997) – analog of M 104.941 for Mercedes-Benz E 280 W124.
- M104.943 (1993 – 1998) – analog of M 104.941 for Mercedes-Benz SL 280 R129.
- M104.944 (1992 – 1998) – analog of M 104.941 for Mercedes-Benz 300 SE W140, S 280 W140.
- M104.945 (1995 – 1997) – analog of M104.941 for Mercedes-Benz E 280 W210.
Problems and shortcomings of Mercedes M104 2.8 engines
The headache of the Mercedes M104 engine is overheating of the rear part of the cylinder head and as a consequence its warping. There is no way to get away from it, as this problem refers to design flaws. Simply put, it is difficult for engineers designing inline engines to avoid operational deformations in a long part at strong temperature differences. The first swallows of an impending malfunction of the M104 engine are oil leaks from under the cylinder head in the front of the cylinder block, usually by 100 thousand kilometers of mileage. The first thing to do is to replace only the front U-shaped gasket. If the inspection of the engine M104 Mercedes can be seen that he “sweats” oil in the rear part, small term can not do, will have to change the PGB (head gasket block). At the same time I advise you to check the valve seats. Sometimes, in the experience of many motorists I know, the deformation of the head stresses the rear stud of the exhaust manifold, which leads to its rupture. If you find that the stud is broken, your motor will not do without head grinding.
Another serious problem can occur if you do not use this engine properly. I strongly advise you to change the oil in the engine in time, and use only high quality oils. Otherwise the following will happen. In the engine block M104 to combat the overheating of the pistons are installed nozzles that supply oil to the skirts of the pistons, so if the nozzle is clogged fifth or sixth cylinder as a rule the result is one – scoring piston engine Mercedes M104 and the appearance of knocking in the cylinder block. After such a diagnosis, major repairs cannot be avoided.
Also from known to me causes of engine overheating are clogged by street garbage radiator cells or faulty viscoil. In summer heat they will definitely show themselves and additional fans installed in front of the radiator will not cope with blowing.Normal washing from outside will not help to clean the dirt between radiators, you will have to disconnect them. Have this done at a service center or by a reputable craftsman. The fan viscoil should be switched on at 90-100°C. With normal maintenance of the car its service life is 100 thousand kilometers. Additional fans are switched on at 103-107°C. On Mercedes W202 two electric fans are installed, on Mercedes W210 as a rule one electric fan is another parasitic and is driven by a belt. Watch out for this, there is a breakdown or just a slip of the belt, the result is twice reduced efficiency of blowing. And we already know that the main thing for the M104 engine is normal operating temperature.
It is necessary to monitor the integrity of the main cooling fan. If even slight deformation of fan blades is detected, it should be replaced immediately. Otherwise, the fan may rupture at high speeds, the consequence of which will be punctured through the hood, mangled pipes, radiator diffuser and the radiator itself. On Mercedes such a breakdown is very rare, more often it happens on BMW engines, but it does happen.
ENGINE RATING: 5-