Engine BMW S50B32

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 S50B32 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.


Manufacturer Munich Plant
Also called S50
Production years 1995-2000
Cylinder block alloy cast iron
Fuel system injector
Configuration inline
Number of cylinders 6
Valves per cylinder 4
Piston stroke, mm 91
Cylinder bore, mm 86.4
Compression ratio 11.3
Displacement, cc 3201
Power output, hp 321 /7400 rpm
310 /7400 rpm
Torque output, Nm / rpm 350 /3250 rpm
340 /3250 rpm
Max engine speed, rpm 7600
Fuel type petrol
Euro standards Euro 2
Weight, kg 154
Fuel consumption, L/100 km
— city
— highway
— combined
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
Normal engine operating temperature, °C ~90
Engine lifespan, km ~400 000
— 6MT
Getrag 420G
Getrag 420G
Gear ratios 1 — 4.23
2 — 2.51
3 — 1.67
4 — 1.23
5 — 1.00
6 — 0.83
Final drive ratio
— 6MT

Disadvantages of the S50B32 engine

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 triples, 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, throttle position sensor, 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.

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