The 3.0-liter (2986 cc) M30 engine is known as the M30B30. The Bosch D-Jetronic mechanical fuel injection system was the first fuel-injected version of the 2,986 cc (182.2 cu in) M30, which made its debut in the E9 3.0 CSi in 1971. Bosch L-Jetronic electronic fuel injection replaced the previous fuel injection system in 1976. Depending on the model year and whether a catalytic converter is installed, the M30B30 can generate up to 147 kW (200 PS; 197 bhp) and 272 Nm (200 lb⋅ft). 9.2:1 is the compression ratio. The compression ratio with a catalytic converter is 9:1.
Specifications
| Manufacturer | Munich Plant |
| Also called | M30 |
| Production years | 1971-1994 |
| Cylinder block alloy | cast iron |
| Fuel system | carburetor/injector |
| Configuration | inline |
| Number of cylinders | 6 |
| Valves per cylinder | 2 |
| Piston stroke, mm | 80 |
| Cylinder bore, mm | 89 |
| Compression ratio | 9.0 / 9.2 |
| Displacement, cc | 2986 |
| Power output, hp | 184/5800 / 188/5800 / 197/5800 |
| Torque output, Nm / rpm | 255/3500 / 260/4000 / 275/4000 |
| Fuel type | petrol |
| Weight, kg | ~135 |
| Fuel consumption, L/100 km — city — highway — combined |
16.3 7.6 11.0 |
| 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 |
| Oil change interval, km | 7000-10000 |
| Normal engine operating temperature, °C | ~90 |
| Engine lifespan, km | ~400 000 |
Frequent problems
Overheating and cylinder block cracks are the primary issues with BMW M30B30 engines. Many owners of six-cylinder cars experience overheating. This issue needs to be resolved quickly and not initiated in order to avoid driving the cylinder head. A dirty pump, radiator, thermostat, or air jams in the unit’s cooling system can all cause the motor to overheat.
When oil is left in the threaded wells after the motor is disassembled, cracks develop. They develop around the cylinder head bolt threads. Increased antifreeze consumption and the presence of an emulsion in the oil could be signs of cylinder block cracks. The masters advise purchasing and installing a cylinder block free of cracks, but occasionally they attempt to fix the issue by making repairs.
BMW M30B30 engines have issues with the gas distribution mechanism when the valve cannot be adjusted because of their extended service life. Replacing eccentrics, bushings, and valves is the answer.
The mass air flow sensor may have issues because the units’ resources have been exhausted, including as a result of their intense, frequently aggressive operation.