At one time, the M50 engine was a real favorite of BMW. He replaced the M20 engine in 1991. New engine was developed in two variations - 2.0 and 2.5 liters. However, his “life” on the market was short-lived: the release of “fifty” was discontinued already in 1996, when new modification with an aluminum block - she was assigned the index M52.

Device M50

The M50 engine was installed on the E34 and E36 models. In 1992 the engineers concern BMW gave the M50 a new gas distribution system called VANOS. The main “chip” of the innovation was intake camshaft, which made it possible to increase engine thrust at low and medium speeds without loss at high ones.

The design is a standard 6-cylinder engine, which turned out to be a cast-iron block with an aluminum head. However, compared to the M20 predecessor, the BMW M50 was a pretty impressive step forward: 24 valve system gas distribution with two camshafts driven by a chain and valve drive through hydraulic compensators. The ignition system has also undergone changes - it has become entirely electronic, the distributor was removed as unnecessary and an ignition coil was added to each candle.

The M50 became the most successful and reliable engines from BMW, so they got a further life - based on the M50, modifications such as the 3-liter M3e36 with a power of 240 hp were assembled. and Alpina B3 with 250 hp The last option was for American market. The weight of the engine was about 136 kg.

M50 modifications

Engine modification	Cylinder diameter, mm	Piston stroke, mm	Volume, cm3	Compression ratio	Power, hp	Torque, Nm	Max. rpm
М50В20	80	66	1991	10,5:1	150 at 6000 rpm	190 at 4700 rpm	6500
М50В20TU VANOS	80	66	1991	11:1	150 at 5900 rpm	190 at 4200 rpm	6500
M50B25	84	75	2494	10:1	192 at 6000 rpm	245 at 4700 rpm	6500
M50B25TU VANOS	84	75	2494	10,5:1	192 at 5900 rpm	245 at 4200 rpm	6500

Flaws

Despite all the “luck” of the M50, it still turned out to be not ideal, like all “long” engines: with severe overheating, the gas joint loses its tightness, as a result of which cracks form on the cylinder head. Excessive consumption oil, which normal mode operation is 1 liter per 1000 km, observed already after 300-400 thousand kilometers. The consequences are sad - burn out exhaust valves, and in some cases, due to local overheating, cracks form between them.

Many parts manufacturers install plastic parts into the water pump, causing damage to the bearings and pump impeller. Often, with low qualifications of the craftsmen, the result of the repair is incorrectly installed camshafts. The motors of the first years of production suffer from failures of the ignition coils and cases of burnout of the power keys that control the ignition. But the erosion of the liners is less common than in the 40 series motors. Many 50 series engines have oil leaks - under the gaskets of the pan, valve and front covers, at the connection of the cylinder block with the oil filter and the dipstick ring.

Some M50s suffer from cylinder shutdown, which in turn cuts off the fuel supply. To turn them on, it is often necessary not only to eliminate the malfunction, but also to clean the memory. But, at least, these systems do not suffer too much from breakdowns associated with a lambda probe - an oxygen sensor.

Advantages

The M50 has a number of differences from the first generation engines, which, of course, was a big step forward for BMW. It was this engine with its 4 valves per cylinder that founded the fashion for the “explosive” engines of the German auto giant, which has survived to this day.

The M50 was the last unit to use the “cast iron block and aluminum cylinder head” combination, which was a truly faithful and reliable design.

The M50 also set the popular standard of “1 Nm per 10 cm 3 cylinders”, which was unattainable in the engines of the old series. The engine perfectly adapted to 95 gasoline, which, however, cannot be said about the 2-liter versions - even this is not enough for them octane number. But this problem is solved to some extent with the help of knock sensors. According to the results, despite its inherent shortcomings, the BMW M50 became the best in the history of the concern, both in terms of technical and consumer data.

The work of the BMW M50 engine (video)

Reliability, problems and repair of the BMW M50B25 engine

In 1990, to replace the popular inline six BMW M20B25, a new one, much more advanced and powerful, called BMW M50B25 (popularly nicknamed "Slab"), from the new M50 family (the series also includes M50B20, M50B24, S50B30, S50B32). The main difference between the M20 and M50 engines lies in the cylinder head, in the new engine the head was replaced with a more advanced two-shaft, 24-valve with hydraulic compensators (valve adjustment does not threaten).

Diameter intake valves 33 mm, exhaust 30.5 mm. Used camshafts with phase 240/228, lift 9.7/8.8 mm. And also applied an improved lightweight intake manifold. Bosch Motronic 3.1 engine management system. The timing drive in the new M50 engines has also changed, now a chain is used instead of a belt, the service life of which is 250 thousand km (usually it runs longer). In addition, individual ignition coils, an electronic ignition system, other pistons, lightweight connecting rods 135 mm long are used. Nozzle size M50B25 - 190 cc.

Since 1992, M50 engines have been widely known system variable valve timing intake shaft Vanos, and such motors became known as M50B25TU (Technical Update). In addition, these engines use new connecting rods with a length of 140 mm and pistons with a compression height of 32.55 mm (38.2 mm on the M50B25).

The control system has been replaced with Bosch Motronic 3.3.1. These power units were used on BMW cars with the 25i index. Since 1995, the M50V25 engine has been replaced by a new improved M52V25 engine, and in 1996 the production of the M50 series was completed.

BMW M50B25 engine modifications

• M50B25 (1990 - 1992) - base engine. Compression ratio 10, power 192 hp at 5900 rpm, torque 245 Nm at 4700 rpm.
• M50B25TU (1992 - 1996 onwards) - a system for changing the valve timing on the Vanos intake was added, the connecting rod and piston group was changed, other camshafts were installed (phase 228/228, lift 9/9 mm). Compression ratio 10.5, power 192 hp at 5900 rpm, torque 245 Nm at 4200 rpm.

Production	Munich Plant
Engine brand	M50
Release years	1990-1996
Block material	cast iron
Supply system	injector
Type	in-line
Number of cylinders	6
Valves per cylinder	4
Piston stroke, mm	75
Cylinder diameter, mm	84
Compression ratio	10.0 10.5(TU)
Engine volume, cc	2494
Engine power, hp / rpm	192/5900
Torque, Nm/rpm	245/4700 245/4200(TU)
Fuel	95
Environmental regulations	Euro 1
Engine weight, kg	198
Fuel consumption, l/100 km (for 320i F30) - city - track - mixed.	11.5 6.8 8.7
Oil consumption, g/1000 km	up to 1000
Engine oil	5W-30 5W-40 10W-40 15W-40
How much oil is in the engine, l	5.75
When replacing pour, l	4
Oil change is carried out, km	7000-10000
Operating temperature of the engine, hail.	~90
Engine resource, thousand km - according to the plant - on practice	- 400+
Tuning, HP - potential - no loss of resource	1000+ 200-220 -
The engine was installed	BMW 325i E36 BMW 525i E34

The BMW concern (Bayerische Motoren Werke) is one of the world's largest manufacturers of cars and motorcycles. However, the production of engines internal combustion occupies in the structure of its production far from last place. It suffices to note that the line power units produced by the concern, includes both gasoline and diesel:

• BMW INLINE ENGINES (M RANGE)

In the automotive powertrain market, the most famous are in-line six cylinder engines concern BMW. Various motor modifications model range M were installed on BMW 3 and 5 series cars in different years:

m10 (1962-1988), m20 (1977-1987), m40 (1988-1994), m50 (1990-1995), m52 (1994-2001), m54 (2001-2006).

In 2005, the engines of the M range were replaced by a new generation of BMW engines - the N series. Its first representative was the N52 engine.

• M50 SERIES ENGINES

In the days of the USSR, the purchase of a BMW car was pipe dream every car enthusiast. However, during the time of "perestroika" did many manage to realize their dream? and on domestic roads in enough in large numbers these previously unavailable models appeared.

It was at this time that the BMW concern mass-produced and installed engines of the M lineup on their cars, specifications which many times exceeded the parameters of domestic automobile engines.

Specifications

m50b25 engine:

PARAMETER	MEANING
Working volume of cylinders, cu. cm	2494
Rated power, l. With. (at 5900 rpm)	192
Maximum torque, Nm (at 4700 rpm)	245
Number of cylinders	6
Number of valves per cylinder, pcs.	4
Total number of valves, pcs.	24
Cylinder diameter, mm	84
Piston stroke, mm	75
Compression ratio	10...10,5
The scheme of the cylinders	1 - 5 - 3 - 6 -2 - 4
Fuel	Unleaded gasoline AI-95
Fuel consumption, l / 100 km (city / mixed / highway)	11,5/8,7/6,8
Lubrication system	Combined (spray + under pressure)
Engine oil type	5W-30, 5W-40, 10w-40, 15W-40
Amount of engine oil, l	5.75
Cooling system	liquid, closed type with forced circulation
Coolant	Based on ethylene glycol
Motor resource, thousand hours.	400
Weight, kg	198

The engine was installed on cars produced by the BMW concern: Series 3 - BMW 320 E36, 325i E36; 5 series - BMW 520 E34, 525i E34.

Description

The start of the M lineup was laid by 4-cylinder engines of the M10 series with a volume of 1.5 ... 2.0 liters. High specifications various modifications these motors were largely determined by the use of:

• two carburetors;
• fuel injection;
• turbocharging.

Design features of M10 series motors:

• The cylinder diameter is larger than the piston stroke.
• Number of main bearings - 5.
• The intake and exhaust manifolds are located on opposite sides of the power unit.
• The cylinder block body is made of cast iron, and its head is made of aluminum.

NOTE: All M range engines use a cast iron cylinder block + aluminum head combination. Only on engines of the N52 series, this pair began to be made from a magnesium-aluminum alloy.

At the end of 1988, on the basis of the m10 engine, New episode 4-cylinder engines, which received the index m40. Structurally, it was distinguished by the presence of:

• valve hydraulic compensators;
• belt drive gas distribution mechanism (timing) SOHC.

Engines BMW Series m40 had:

1. higher power;
2. increased torque at low and medium speeds crankshaft;
3. less weight;
4. reduced dimensions.

However, the power of 4-cylinder engines for heavy BMW cars was sorely lacking. Therefore, in the mid-60s, the company's management decided to develop a model range of power units with 6 cylinders and seven crankshaft bearings.

It was started by the M30 family of in-line engines with a cylinder capacity of 2.5 to 3.5 liters. Despite the high technical specifications these engines had a number of disadvantages, among which the main ones were heavy weight, significant dimensions and high cost.

In 1977, having started developing more modern, highly economical and low-cost cars, the concern's engineers created a number of new modifications of 6-cylinder engines based on the M30.

The first of these was a series of M20 engines with 2 valves per cylinder and a SOHC timing belt drive. The power units of this series were replaced by the m50 series engines, each of which is an in-line 6-cylinder Gas engine, which, unlike its predecessor, has 4 valves per cylinder and two camshafts(DOHC system) with hydraulic valve lifters.

In addition, in the m50 series engines, the timing is driven by a chain whose service life is at least 250 thousand kilometers. The presence of hydraulic valve compensators, which eliminate the need to adjust the latter, and an “indestructible” timing chain have greatly simplified the maintenance of these power units.

In addition, in 1992, the engines of this family received new system variable valve timing Vanos (Technical Update), developed by BMW.

The system allowed:

1. Increase torque by low revs crankshaft.
2. Reduce fuel consumption.

Installation Vanos systems required replacement:

• parts of the connecting rod and piston group;
• camshafts;
• electronic control unit (ECU).

In the future, the Vanos system has undergone a number of changes. So on the N52 engine, a more advanced system for changing the valve timing on two Double Vanos shafts was installed.

Maintenance

Regular maintenance of the m50 series motors is reduced to timely replacement engine oil.

The regulatory documents of the concern recommend changing the oil every 15,000 km, however, given the condition of our roads and the quality of the fuel, experts from domestic service stations advise this procedure to be carried out after 7,000 km. At the same time, it is necessary to ensure that the filled engine oil approved BMW LL-98 or LL-01.

Faults

The m50b25 engines are considered one of the most reliable engines produced by the BMW concern. However, they, especially after the mileage exceeds 200 thousand km, are characterized by a number of common malfunctions.

FAULTS	CAUSES
The engine is unstable.	May be faulty: 1. Ignition coils. 2. Spark plugs. 3. Nozzles. 4. Idling valve. 5. Position sensors throttle valve, temperature, lambda probe.
Loss of power.	The Vanos gas distribution system has failed.
The engine is overheating.	Possible failure: thermostat; cooling system pump (pump); radiator.
Increased engine oil consumption.	Check valve cover gaskets and sump for oil leaks.

tuning

Unlike the engines of the N52 series, which are practically not amenable to tuning, the motors of the M range can be modified independently. For example, there are several tuning options with which you can increase the power of the M50b25 engine:

1. The easiest way is to install a long-stroke crankshaft (stroker), which was installed in the m54b30 engine. At the same time, it is necessary to purchase and install a number of parts of this power unit: a connecting rod and piston group; nozzles; root inserts. By setting the ECU accordingly, you can get a power of about 230 hp. With.
2. Maximum power without the use of a turbine can be obtained by installing: Schrick 284/284 camshafts; nozzles from sports engine S50; six-throttle inlet; equal length exhaust manifold; once-through exhaust system etc. Correct setting The ECU will allow you to bring the engine power up to 280 hp. With.
3. If you set out to increase the engine power to 500 liters. s., then this can be done by installing on it: a turbo kit with Garret GT 35; connecting rod and piston group for a compression ratio of 8.5; nozzles 550 ss.

Spare part requestViber 89639932224

Engine BMW M50B20TU 206S2

Instead of reliable, but morally obsolete engines M20, the designers of the BMW concern in 1990 developed a completely new six-cylinder in-line power unit, designated the M50. It became so successful that it served as the basis for a number of bavarian motors next generations and had several modifications that differ from each other in the presence of additional components, systems, as well as torque characteristics. M50 engines are equipped with two camshafts and four valves per cylinder. This made it possible to significantly increase the efficiency of the use fuel-air mixture and, as a result, increase the power of the motor. In addition, in order to increase reliability, the timing belt drive was replaced with a chain drive. The cost is 35,000 rubles.

Engine Specifications M50B20TU (206S2)

Engine model: M50B20TU (206S2)

Volume: 1991 cm3

Power: 150 HP

Number of cylinders: 6

Starting in 1992, the M50 power units began to be equipped with the proprietary VANOS variable valve timing system, with which it was possible to significantly reduce fuel consumption and increase torque (especially at low revs). These engines were produced until 1995 and were equipped with such BMW car models as the E36 320, E36 325, E34 520 and E34 525.

As regards such important characteristics, as reliability and resource, then they are at the M50 power units on high level. Station Masters Maintenance note that the vast majority of problems with them are caused by improper operation and use poor quality oil and fuel.

M50 is a fairly popular motor that BMW company produced from 1991 to 1996. in 1994, a modification was born, the peculiarity of which was the aluminum block. This variation was also known as a "slab".

The fiftieth was installed on the e34 and e36 models. In 1992, it was equipped with a variable valve timing system called Vanos. It was installed to increase engine thrust at low and medium speeds, while not affecting high speeds.

Specifications and Description

The 50 series M family has several types of powertrains. It includes M50B25 and M50B20, which are remembered by many motorists as technically reliable engines. The closest modern relative is the bmw m5 e60.

Parameter	Cylinder diameter, mm	Piston stroke, mm	Engine capacity, cm 2	Compression ratio	Power, hp	Torque, Nm	Max. rpm
Modification
BMW М50В20	80	66	1991	10,5:1	150	190	6500
BMW М50В20 TU VANOS	80	66	1991	11:1	150	190	6500
BMW M50B25	84	75	2494	10:1	192	245	6500
BMW M50B25 TU VANOS	84	75	2494	10,5:1	192	245	6500

The M50 engine was produced in only two versions - 2.0l and 2.5l.

Advantages. The M50 engine marked the beginning new fashion on the aggressive nature of BMW engines, which has survived to this day. Also, this model set a standard that no one violated - "1 NM per 10 cm 3 of cylinder volume."

The BMW M50 engine was the last in its lineup, in which a truly legendary bunch was used in the form cast iron block and aluminum cylinder head.

Flaws. Despite the fact that among motorists bmw engine m50 is considered one of the most reliable motors for the entire time of production, with improper operation, the appearance of such problems is inevitable:

1. Overheating of the power unit
2. antifreeze leak
3. Ignition coil failure
4. Oil leak
5. Fuel shutdown

Service M 50

The M50, M50B20 and M50B25 modifications have an excellent reputation, but do not tolerate careless maintenance. The conditions for their service are as follows:

1. Oil change - every 10-12 thousand km. Oil must be used only recommended by the manufacturer.
2. Timing chain - its average resource is 250-300 thousand km, after which it stretches and needs to be replaced.
3. Nozzles and candles - every 50-80 thousand km.
4. Repair of the Vanos system - carried out after 200-300 thousand km.

M50 engine repair

The most common mechanisms that fail are the failure of the cooling system pump, the radiator fan drive and failure oil filter.

Replacing the fan and viscous coupling

The viscous coupling needs to be replaced if the fan hub is seized, as well as with increased axial or diametral clearance, or with increased oil consumption.

Withdrawal process:

1. Removing the fan shroud by removing the spacer clip pins on the top of the shroud
2. Unscrewing the fixing nut of the fan to the water pump hub
3. Direct fan removal
4. Removal of the viscous coupling is carried out by turning four mounting bolts

Installation process:

1. Installing the viscous coupling and tightening the fixing bolts to 9 Nm.
2. Installing the fan on the pump hub and tightening the nut to 25 Nm
3. Installing the fan shroud, making sure both bottom tabs fit into the slots on the heatsink
4. Installation of spacer clamps and their fixation with pins

Removal and installation of the water pump

Many owners of power BMW units m50 complain about the frequent failure of the water pump. But, as practice shows, it is enough just to change the product yourself. Consider the process of replacing the pump.

Withdrawal process:

1. Disconnecting the ground wire from the battery
2. Draining the coolant
3. Removing the fan
4. Loosening the pulley bolts
5. Removing the V-belt
6. Loosening the four bolts of the pulley and removing the latter from the pump hub
7. Disconnecting the water pump hoses
8. Loosening the fixing bolts and removing the pump

Installation process:

1. Cleaning the mounting surface
2. O-ring installation
3. Installing the pump and evenly tightening the mounting bolts
4. Connecting the hoses to the water pump and securing them with clamps
5. Drive pulley installation
6. Installing and tensioning the V-belt
7. Fan installation
8. Filling the cooling system

Flushing the cooling system

Frequent heating of the motor may mean that the cooling system is clogged. Therefore, the motorist often needs to clean this unit. This can be done with auto chemicals or home remedies such as citric acid.

1. Removing the bumper, opening the cap on the reservoir and opening the radiator cap
2. Closing the lid on the tank, compressor purge into the hole for the screw to remove air
3. Unscrewing the coolant drain plug from the block, draining the coolant
4. Filling the system with water, adding 7 minute wash Hi Gear
5. Starting the engine and waiting seven minutes
6. Cooling the engine and draining the fluid
7. Closing all plugs, pouring 5-6 liters of water
8. Opening one plug and running water with a compressor
9. Repeat step 8 until clear water starts to come out
10. Filling the system with distilled water, starting the engine and warming it up to operating temperature. Cooling the engine and draining water
11. Slow filling of the system with new antifreeze and pumping at high speeds
12. Winding up new cover tank, warming up to operating temperature

Change oil and oil filter bmw m50 engine

You can change the engine oil on the M50 engine with your own hands. Consider how to perform this operation without contacting a car service and saving money:

1. Loosening cap nuts
2. Withdrawal valve cover
3. Removing the old gasket

Conclusion

You can change the engine oil on the M50 engine with your own hands.

Consider how to perform this operation without contacting a car service and saving money:

1. Heating the oil, unscrewing the oil drain
2. Unscrewing the drain bolt, draining the oil
3. Unscrewing the oil filter
4. Replacing the filter element and sealing rubber
5. Filling oil through a special neck, parallel checking its level on the dipstick

Replacing the valve cover gasket

One of the problems of engines of the 50th family, and more precisely the engine m50b20, is a sample of the valve cover gasket. You can change this part with your own hands. Consider the sequence of actions:

1. Removing both plastic protective covers
2. Disconnecting the crankcase ventilation pipe from the valve cover
3. Disconnecting coil wires and removing ignition coils
4. Loosening cap nuts
5. Removing the valve cover
6. Removing the old gasket
7. Cleaning the surface of the cover from the sealant
8. smearing new gasket sealant and assemble everything in reverse order

Conclusion

The M50 family replaced the M20 back in 1990, and had a few differences, but they, in turn, made it possible to significantly increase the power characteristics and reliability. For changing bmw motor M50B20 and M50B25, improved and upgraded bmw m5 e60 came.