Overrun

As a coasting operation or sliding operation , the driving condition is referred to in a motorized vehicle, is therefore kept in rotation dragged in the case of non-isolated power circuit (for. Example, when not met by coupling) of the engine by the vehicle. In modern vehicles, an overrun fuel cutoff interrupts the fuel supply. In some electric vehicles, and in particular in hybrid vehicles, the energy released during overrun is used to charge the accumulator.

In two-stroke engines with mixture lubrication , overrun operation is problematic because the fuel flow is too low for its speed, and the engine lacks the necessary lubrication after a short time, which can result in engine damage. For this reason, many vehicles with two-stroke engines have a freewheel (partially lockable or only effective in some gears), so that a (longer lasting) overrun is prevented.

literature

• Peter Gerigk, Detlev Bruhn, Dietmar Danner: Automotive engineering. 3rd edition, Westermann Schulbuchverlag GmbH, Braunschweig, 2000, ISBN 3-14-221500-X