To Adjust the Pinion

NOTE: The following work must be carried out before assembly is started.





GENERAL
Certain particulars are stamped in the end face of the pinion to enable adjustments to be carried out to the distance between the pinion and the crown wheel center.

Particulars on end face of the pinion

+3 = Dimension for setting the pinion
R913 = Matching number which is also stamped on the crown wheel
0 = Pinion not offset - its centerline intersects the crown wheel centerline. All pinions are stamped 0, and this figure is therefore irrelevant to the adjustment.

BEFORE MEASURING
Note the following when measuring the pinion setting:
Car with manual gearbox: The output shaft bearings should be preloaded so that the torque necessary to rotate the pinion is 2.5 +/- 0.5 Nm (1.85 +/- 0.4 lb ft). This applies to new, lightly oiled bearings. The corresponding figure for older bearings (in service more than 2,000 km or 1,200 miles) is 1.3 +/- 0.5 Nm (0.96 +/- 0.4 lb ft).





Measuring tool 83 90 155 consists of a jig to which a dial indicator is secured. A slip gauge is available for adjusting the dial indicator, and this should be placed against the calibration pads of the jig. The distance between these pads and the centerline of the crown wheel is always 60.000 mm (2.360 in) (see figure). The procedure for measuring the pinion setting is as follows:

TO MEASURE





1. Fit two guide pins (tool 87 90 438) to the gearcase. Then place the shims - note their locations.





2. Fit the output shaft with bearing housing. First fit two bolts and tighten them lightly. Then remove the guide pins and fit the remaining bolts. Apply Loctite 242 to the bolts. Then tighten the four bolts to a torque of 23-28 Nm (17-21 lb ft).





3. Fit tool 83 90 155 into the differential bearing seats and check the output shaft position (see figure). The appropriate value is stamped in the end face of the pinion. For reading procedure, see under the heading Shimming, item 2.