In order to check the coupling of the pinion and crown,
cover the pinion teeth, on the drive side, with one of
the many products available on the market.
Apply a universal extractor «A» - Fig. 15-17 with an
appropriate spacer «B» - Fig. 15-17, so that the
bored pivot - crown unit is held tightly against the
cover side; rotate pinion «C» - Fig. 15-17 in the
working operation direction, whilst locking the crown.
Remove the extractor, remove the cover and check
the contact zone on the pinion teeth.
Contact control (Fig. 15-18)
■ if the contact is correct the traces on the pinion teeth will be seen as shown in detail 1 (the pinion is seen from
the drive shaft side);
■ if the contact is the same as detail 2 the crown is too near to the pinion rotation axis: move the crown away
by increasing the thickness of the spacers between the box and the cover;
■ if the contact is the same as detail 3 the pinion is too near to the crown rotation axis: move the pinion away
by reducing the thickness of the spacers between the bearings and the pinion;
■ if the contact is the same as detail 4 the pinion is too far away from the crown rotation axis: move the pinion
closer by increasing the thickness of the spacers between the bearings and the pinion;
■ if the contact is the same as detail 5 the crown is too far away from the pinion rotation axis: move the crown
nearer by reducing the thickness of the spacers between the box and the cover;
■ with a correct coupling the play between the pinion teeth and the crown teeth should be between 0.10 mm and
0.15 mm.
1
2
A
C
3
4
5
B
15-17
15-18
135