The cylindrical gear drive of the balance shaft module must be installed with a tooth profile clearance of 0.038...0.072 mm. To achieve the required tooth profile clearance, a coating of the appropriate thickness is applied to the new intermediate gear. The coating is located on individual sections of the perimeter on the teeth. Over a short period of time, the coating wears off and the required clearance appears. A new balance shaft module must always be installed with a new intermediate gear with a coating. Replace bolts that were tightened with additional tightening. Risk of slipping of the thrust bearing washer behind the intermediate gear. When installing the balance shaft module, do not loosen the intermediate gear bolt of the shaft more than specified. Mounting position of the thrust bearing washer. Loosen bolt "1" of the intermediate gear by approximately 45°. If the cylinder block does not have installation sleeves for centering the balance shaft module, insert installation sleeves. Install the balance shaft module onto the cylinder block. The intermediate gear coating must not be damaged.
Tighten the balance shaft module bolts.
Fix the balance shaft using the locking device "T10255"; if necessary, rotate the shaft. The journal of the locking device must enter the groove of the balance shaft.
Carefully place the gear on the balance shaft, moving the intermediate gear slightly to the side. The coating of the intermediate gear must not be damaged. The threaded holes of the balance shaft must be located, if possible, in the center of the longitudinal holes of the balance shaft gear. If the longitudinal holes in the balance shaft gear do not coincide with the threaded holes, it is necessary to turn the gear by the corresponding number of teeth and put it on again. Tighten the bolts "arrows" of the balance shaft gear. Remove the locking device "T10255".
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The following 3 stages of work must be completed simultaneously (assistance from a second mechanic is needed). Press the intermediate gear "3" with force, if necessary with a wooden block, "in the direction of the arrow" into the gear mesh of gear "2" and balance shaft gear "1". At the same time, slightly turn the balance shaft gear counterclockwise. Tighten the intermediate gear bolts. Remove the high-pressure fuel pump retainer "3359". After installation, there should be no play in the intermediate gear. This can be checked manually, without applying much force.
Installation is in reverse order, taking into account the following: Install the oil pan.
(The original material is located on the website: «AudiManual.ru»)