10.1. General information
The present Head is devoted to the description of the components serving for transfer of rotation from a transmission to driving wheels of the car. The driveshaft, assembly of the main transfer and power shafts of the back bridge belong to number of such components.
Engine capacity is transferred from transmission to the back bridge by means of the two-section driveshaft connected behind the central bearing so-called by "the sliding coupling», shlitsevy sliding connection. The sliding coupling allows easy longitudinal movings of the driveshaft. The forward end of the driveshaft fastens to a transmission flange by means of the elastic rubber coupling.
This coupling which is called sometimes by «Guibo», or «a flexible disk», protects the driveshaft and differential from breakthroughs at engine rotation. On some models between a target flange of transmission and the elastic coupling establish a vibration quencher. The middle of the driveshaft is supported by the central bearing established on a rubber pillow for mitigation of vibration of a shaft.
The casing of the bearing is attached by bolts to a car body. The forward end of the driveshaft is combined with transmission by means of centering directing, turned in kardanny to a shaft; the centering directing incorporates to a centering finger on a transmission flange. Hinges are located by Kardannye at the central bearing and at the back end of the driveshaft to compensate transmission and differential movings on their support, and also any deflections of the chassis.
Differential assembly / main transfer
The assembly of differential located in a back part of the car, includes in a behaving gear wheel, a gear wreath (a conducted gear wheel), differential and target flanges. A leading gear wheel which rotates a gear wreath, sometimes call also entrance shaft of differential. It is connected to the driveshaft flange means. The differential fastens bolts to a conducted gear wheel and rotates back wheels through pair of the target flanges attached to power shafts by hinges of equal angular speeds (CV JOINT). The differential allows wheels to rotate with different speeds during commission of turns (the external wheel should move a little quicker internal in view of a difference of radiuses of turn). Assembly of differential fastens bolts to bearing the back bridge and by means of elastic rubber plugs to a body.
Serious repair of components of assembly of differential (a leading gear wheel, a gear wreath and differential) demands a set of special tools and adaptations, and also considerable experience and consequently it is best of all to provide it to specialists of dealer office of the BMW service or a repair truck.
Power shafts and CV JOINTS
Power shafts transfer rotation from target flanges of differential to back wheels of the car. Power shafts are equipped since both ends with hinges of equal angular speeds (CV JOINT).
CV JOINT function generally coincides with function of the standard kardanny hinge, but the CV JOINT can compensate big corners of a deviation of power shafts, than the kardanny hinge. CV JOINTS allow power shafts to transfer rotation to back wheels, moving up and down together with a back suspension bracket, even when differential assembly, power shafts and wheels are not balanced.
Internal CV JOINTS on all models fasten bolts to differential flanges. External hinges are identical to the internal. Each hinge is filled by special greasing and closed by a rubber protective cover. Regularly check a condition of protective covers. Damage of a cover conducts to hinge pollution.
Hinges on the cars described in this Management, are not subject to repair, but they can be removed and cleaned during replacement of protective covers. Both internal, and external CV JOINTS on all models are subject to replacement in an individual order.