Engine BMW S50B30

Engine BMW S50B30

The basic 3-liter version of the sports engine for the sedan, coupe and convertible M3 produced for the European market (S50B30 EU) since 1992. In 1994, this is a 300 hp engine. was installed on the limited edition M3 GTR E36 coupe, and a year later the M3 GT E36 racing model was equipped with a 295-horsepower variant of this unit, with a torque of 324 Nm. In the same 1995, the BMW Motorsport department and Schnitzer Motorsport GmbH modified this power unit for the Australian racing version of the M3-R E36 coupe.


Manufacturer Munich Plant
Also called S50
Production years 1992-1995
Cylinder block alloy cast iron
Fuel system injector
Configuration inline
Number of cylinders 6
Valves per cylinder 4
Piston stroke, mm 85.8
Cylinder bore, mm 86
Compression ratio 10.8 (EU) / 10.5 (US)
Displacement, cc 2990
Power output, hp 243/6000 / 286/7000 / 295/7100
Torque output, Nm / rpm 305/4250 / 320/3600 / 323/3900
Max engine speed, rpm 7280 (EU) / 6500 (US)
Fuel type 95
Euro standards Euro 1
Weight, kg 151 (EU) / 135 (US)
Fuel consumption, L/100 km
— city
— highway
— combined
Oil consumption, gr/1000 km up to 1000
Recommended engine oil 5W-30 / 5W-40 / 5W-50 / 10W-40 / 15W-40
Engine oil capacity, liter 7.0
Oil change interval, km 7000-10000
Normal engine operating temperature, °C ~90
Engine lifespan, km
— official information
— real

— 5MT
— 5AT
ZF Type C
ZF 5HP18
Gear ratios, 5MT 1 — 4.20 / 2 — 2.49 / 3 — 1.66 / 4 — 1.24 / 5 — 1.00
Gear ratios, 5AT 1 — 3.67 / 2 — 2.00 / 3 — 1.41 / 4 — 1.00 / 5 — 0.74
Final drive ratio
— 5MT
— 5AT
— 5MT (M3 GT, M3 CSL LTW)

Frequent problems

Typical malfunctions of the S50B30 engine include: increased oil consumption, overheating, leaks, floating speed, problems with the Vanos system, intake air leaks.

The motor is prone to overheating. If you notice a problem, you need to check the operation of the cooling system: radiator, thermostat, pump. Overheating can be caused by air blockages in the system and broken radiator caps.
Engine BMW S50B30 under the hood
Unstable turnovers are often caused by a failed KXX. After cleaning the valve, operation is restored. When the problem persists, you should check the TPS – throttle position sensor, temperature sensor, lambda probe, sometimes it is enough to clean the throttle valve.

If the engine is troit, check the ignition coils and injectors and spark plugs. In case of problems with the Vanos system, the engine begins to rumble, power decreases, the speed becomes unstable. In this situation, you need to buy a Vanos repair kit.

Motors with high wear are characterized by high oil consumption – up to 1 liter per 1000 km. Even after a major overhaul of the engine, consumption is practically not reduced. It is necessary to check whether the gaskets of the sump and the valve cover are not leaking, also exclude leaks through the oil dipstick. Check the integrity of the expansion tank causing antifreeze leakage. Problems can be caused by crankshaft, camshaft, temperature sensors. The main reason for the failure of reliable S50B30 engines is the age of the power units.

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