Recalculating adjusting shim S4

This adjustment is required if end shield, needle-roller bearing inner race for 1st gear loose gearwheel, synchronizer hub for 1 st and 2nd gear, needle-roller bearing inner race for 2nd gear loose gearwheel, gearwheel for 3rd gear, spacer sleeve and gearwheel for 4th gear have been replaced.

This adjustment allows the preload of the tapered roller bearings for the drive pinion to be reset.

= Housing depth of the end shield

= Length of inner race/needle roller bearing for 1 st gear loose gearwheel

= Length of hub of synchronizer hub for 1 st and 2nd gear

= Length of inner race/needle roller bearing for 2nd gear loose gearwheel

= Length of 3rd gear gearwheel

Dim. ,,t = Length of spacer sleeve

Dim. ,,g" = Length of 4th gear gearwheel

Dim. ,,S4" = Thickness of adjusting shim S4

1 - End shield

3 - Needle roller bearing inner race for gearwheel of 1st gear

4 - Synchronizer hub for 1 st and 2nd gear

5 - Needle roller bearing inner race for gearwheel of 2nd gear

6 - Gearwheel for 3rd gear

7 - Spacer sleeve

8 - Gearwheel for 4th gear

9 - Drive pinion

A - Replacing the end shield

- Measure housing depth "a" of old and new end shield and determine difference

Example: Old end shield

Housing depth „a" = 118.40 mm New end shield

Housing depth "a" = 118.65 mm

Difference = 0.25 mm

If the new end shield is deeper - fit thicker

If the old end shield is deeper - fit thinner

Example:

Old shim 0.95 mm

Difference + 0.25 mm

New adjusting shim "S4" 1.20 mm

The following shims are available as spare parts: Thickness in mm 0.45 - 0.50 - 0.55 - 0.60 - 0.65 - 0.70 - 0.75 -0.80 -0.85 - 1.25

B - Replacing needle roller bearing for 1st gear

Calculate length "b" of the inner race of the old and new needle roller bearings and determine thickness

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1189-34

Example:

Difference = 0.05 mm

If the new inner race is longer - fit correspondingly thinner shim ,,S4".

If the old inner race is longer - fit correspondingly thicker shim ,,S4".

Determine difference of dimensions between old and new parts in the same manner for dimensions "c" to "g" - pages 34 - 29 and determine required adjusting shim "S4".

D - Replacing only drive set refer to page 39-17.

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