Abstract: A valve unit for internal combustion engines with a drive unit, a gear mechanism, a valve rod and a valve disk, the gear mehanicm being provided with an eccentrically disposed coupling part which is connected coactingly with the valve rod, the coupling part being a bearing element which serves as a connection means with the valve rod. A combustion-air intake-channel portion and an exhaust-gas return unit are integrally combined with the valve unit.

Abstract: A cooling system of a motor-vehicle internal-combustion engine has a pump driven by a current-consuming electrical motor. The liquid fill level of a this system is determined by continuously and concurrently monitoring current consumption of the electrical motor and generating an output corresponding thereto. The output is continuously compared with at least one threshold and a difference between the output and the threshold is established as the fill level of the cooling system. An alarm signal is emitted when the output drops below the threshold. When the output is compared with two separate such thresholds one of which is lower than the other, the signal is emitted when the output drops below the lower threshold. It is also within the scope of this invention to emit the alarm signal when the output drops to a level somewhat above the threshold, the difference being determined electronically by the control system serving as comparator.

Abstract: A cooler for the water circulation system of a combustion engine has a motor driven pump mounted directly on the cooler and connected via a flat surface with a plate provided with a three-way valve. The flat surface has an inlet and outlet connected to the plate.