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Engine mountings

Engine mountings


Background

For efficient damping of engine movements, the left and right engine pads are hydraulic. Their most efficient range is between idling speed and around 1800 rpm. Hydraulic engine pads improve:


• damping of horizontal engine movements when accelerating.

• damping of vertical engine movements when driving on bad roads.

• damping of idling vibration.

• sound insulation between engine and body


Description

A hydraulic pad comprises two chambers filled with a special damping fluid. Between the two chambers are a diaphragm and a passage, where the length and cross-sectional area of the passage is the deciding factor for the pad's damping characteristics. The diaphragm absorbs the forces caused by small and normal engine movements.

With bigger engine motion the damping capacity of the membrane is not sufficient, fluid is forced from the upper to the lower chamber and a pressure equalisation occurs. The damping characteristics of the hydraulic mounts are in this way progressive, which means that the resistance from the mounts increases with increased loading.