Turbocharger

BMW diesel engines are equipped with a turbocharger. In the turbocharger on the bottom shaft there are two turbine wheels placed in separate housings. Turbines are driven by useless exhaust gases. They accelerate the supercharger turbines to 120,000 rpm. And since the exhaust and fresh air rotors sit on the same shaft, fresh air is fed into the cylinder at the same speed.

Thanks to a good fill factor, an increase in engine power of up to 100 percent is achieved. The increase in power depends, among other things, on the pressure that is present in the engine of a passenger car, ranging from 0.4 to 0.8 bar (for comparison, the tire pressure is about 1.8 bar). When the pressure is exceeded, set at the factory, a safety valve opens to relieve excess pressure.

Together with the increase in power, the use of a turbocharger allows an increase in torque, which is especially desirable from the point of view of engine flexibility.

Compared to petrol engines, diesel engines do not need to lower the normal compression ratio due to the additional compression, so that the injected fuel is fully utilized even in the low speed range.

The turbocharger is an exclusively precision-manufactured assembly. Therefore, it is recommended to entrust its repair only to a qualified specialist. As a rule, in case of a defect, the turbocharger is replaced as a set.