Engine BMW M30B35 / M30B34

The M30B34 engines sold in Europe and most other markets had a compression ratio of 10.0:1 and produced 160 kW (218 hp). In North America and Japan, the M30B34 had an 8.0:1 compression ratio and produced 136 kW (185 hp). All markets used the Bosch Motronic digital fuel injection system. The bore is 92 mm (3.62 in) and the stroke is 86 mm (3.39 in).

The M30B35 engine has a displacement of 3430 cc (209.3 cu in), despite the “B35” model code. It produces 155 kW (211 hp) at 5700 rpm and 305 Nm (225 lb⋅ft) at 4000 rpm, has a compression ratio of 9.0:1 and uses Bosch Motronic 1.3 digital fuel injection. It was also offered without a catalytic converter for some markets; this version develops 162 kW (220 hp) and 315 Nm (232 lb-ft) at the same engine speed.

Not to be confused with the M30B35LE engine, which has a different cylinder block geometry.


Manufacturer Munich Plant
Family M30
Production years 1982-1992
Cylinder block alloy cast iron
Fuel system injector
Configuration inline
Number of cylinders 6
Valves per cylinder 2
Piston stroke, mm 86
Cylinder bore, mm 92
Compression ratio 8.0
Displacement, cc 3430
Power output, hp 185/5400
Torque output, Nm / rpm 290/4000
Timing drive chain
Fuel type petrol
Weight, kg ~145
Fuel consumption, L/100 km
— city
— highway
— combined
Oil consumption, gr/1000 km up to 1000
Recommended engine oil 5W-30 / 5W-40 / 10W-40/ 15W-40
Engine oil capacity, liter 5.75
Normal engine operating temperature, °C ~90
Engine lifespan, km ~400 000

Frequent problems

Overheating is a common problem in BMW M30B35 engines. It is better not to allow such a situation, so as not to drive the cylinder head. A dirty radiator or pump, thermostat can provoke overheating. Quite often the cause is the plugs in the cooling mechanism.
Owners of cars with a BMW M30B35 engine may encounter cracks in the cylinder block that form around the threads of the cylinder head bolts. Damage occurs due to disassembly of the unit, as well as when oil is not removed from the threads. The presence of cracks is indicated by the rapid consumption of antifreeze when an emulsion appears in the oil. Sometimes they decide to resort to repairs, but it is advisable to buy and install the cylinder block without damage.

Due to long-term operation, motors have problems in regulating the valve of the gas distribution mechanism. In this case, the installation of new eccentrics, guide bushings and valves is required. Due to the impressive age of the engine, malfunctions of the mass air flow sensor may appear.

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