The most powerful variant of the S50 was introduced as a replacement for the 3-liter S50EU. This motor was installed on the updated M3 E36 (except for the models for North America and Canada, which were equipped with the S52 engine). The 3.2-liter BMW S50 engine was supplied with a new Bi-VANOS valve timing system, the valves were changed (the intake diameter was increased to 35 mm, the outlet diameter remained the same, the valve stem thickness decreased from 7 mm to 6 mm). The two-mass flywheel, the outlet system, and the thicker and shorter inlet have also undergone changes.
|Cylinder block alloy||cast iron|
|Number of cylinders||6|
|Valves per cylinder||4|
|Piston stroke, mm||91|
|Cylinder bore, mm||86.4|
|Power output, hp||321/7400 / 310/7400|
|Torque output, Nm / rpm||350/3250 / 340/3250|
|Max engine speed, rpm||7600|
|Euro standards||Euro 2|
|Fuel consumption, L/100 km
|Oil consumption, gr/1000 km||up to 1000|
|Recommended engine oil||0W-30 / 0W-40 / 5W-30 / 5W-40 / 10W-40/ 15W-40|
|Engine oil capacity, liter||5.5|
|Oil change interval, km||7000-10000|
|Normal engine operating temperature, °C||~90|
|Engine lifespan, km
— official information
— SMG I
|Gear ratios||1 — 4.23
2 — 2.51
3 — 1.67
4 — 1.23
5 — 1.00
6 — 0.83
|Final drive ratio
— SMG I
The main malfunctions in the operation of the S50B32 engine: overheating, increased oil consumption, leaks, problems with the Vanos system, floating speed and air leaks at the intake.
The power unit is prone to overheating. If you notice a problem, it is worth checking the condition of the pump, radiator, thermostat. The reasons may be air plugs in the cooling system, as well as a violation of the integrity of the radiator cap.
If the engine is troit, checking the ignition coils, injectors and spark plugs is required. With unstable speeds, the cause is sought in the idle valve, which may fail. It is enough to carry out cleaning, and the motor will be restored. If the problem persists, inspect the temperature sensor, TPS, lambda probe, clean the throttle valve.
The rattling engine causes the Vanos system to break down. As a result, the engine loses power, the speed becomes unstable. To restore functionality, you will need a vanos repair kit.
If you notice an increased oil consumption, check if the gaskets of the valve cover, sump are leaking, exclude leakage through the oil dipstick. The check is necessary for the expansion tank. If it is cracked, antifreeze will leak. Crankshaft, camshaft and coolant temperature sensors break down periodically.