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Engine mountings

Engine mountings


Background

To provide effective dampening of engine movement, the rear and both the right-hand front mountings are of hydraulic type. Their maximum dampening effect is between idling speed and about 1800 rpm.

Hydraulic mountings have the following advantages:


• improved damping of horizontal engine movements during acceleration

• improved damping of vertical engine movements on bumpy roads

• improved damping of engine movement when idling

• reduction of structure-borne sound between engine and body


Description

The hydraulic mounting has two chambers filled with a special hydraulic fluid. Interposed between the two chambers are a diaphragm and a passage, the length and diameter of which determine the damping characteristics of the mounting. The diaphragm absorbs the forces generated by small and normal movements of the engine.

If engine movement is more pronounced, the damping action of the diaphragm is insufficient and fluid is forced from the upper to the lower chamber, thus equalizing the pressure. This gives the hydraulic mountings a progressive damping action, the resistance of the mountings increasing as the load on them increases.

Different gearbox mountings are fitted for automatic and manual gearboxes.