- Detach front end of drive pinion using a puller.
As the drive pinions on the front side are not refaced during production, they retain any notches and material elevations. In order to avoid a measurement error, these elevated sections of material must be removed before the measurement.
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Mount dial indicator (3) onto
dial indicator holder.- Position check pin of
dial indicator (3) onto
measuring piece (2) and reset
dial indicator (3) to zero with a preload of 8 mm.
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Remove measuring piece (2) and insert drive pinion with bearing and magnetic disk (5).
- Read off and note difference dimension of drive pinion on
dial indicator (3).
When reading off, pull drive pinion downwards and turn simultaneously. The difference dimension of the drive pinion is the difference between the length dimension (A) of the
measuring piece (2) and the length dimension (B) of the drive pinion.
- Determine remaining difference dimension "C" to be treated on drive pinion.
To do so, the difference dimension of the drive pinion must 0.03 mm added to it because, when installed in the rear axle housing, the drive pinion is pulled deeper, i.e. by this very 0.03 mm into the rear axle housing.
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- Screw measuring pin into
dial indicator (3).
The measuring pin is included in the tool scope of the
adjustment device (1).
- Press spacer (4) firmly onto
adjustment device (1) and set the
dial indicator (3) to a preload of 2 mm.
The spacer (4) is included in the tool scope of the
adjustment device (1).
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Set dial indicator (3) to zero.
This then sets the
adjustment device (1) to the specified basic dimension for the rear axle housing.
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Insert measuring piece (2) into rear axle housing.
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Insert adjustment device (1) into rear axle housing and determine highest position (vertical position) of measuring pin by turning back and forth.
- Measure production tolerance of rear axle housing.
If there is any deviation towards the center crown gear, the
dial indicator (3) shows more than 2 mm. The dimension difference to the 2 mm must be subtracted from difference dimension "C" of the drive pinion. If there is any deviation towards the drive pinion, the
dial indicator (3) shows less than 2 mm. The dimension difference to the 2 mm must be added to difference dimension "C" of the drive pinion. The difference dimension determined in this way corresponds to the thickness of the shim.
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- Determine difference dimension between specified basic dimension for rear axle housing and basic dimension engraved on crown gear.
Example:
Specified basic dimension for rear axle housing 66.00 mm Basic dimension engraved on crown gear 66.02 mm Difference dimension -0.02 mm
The difference dimension between the specified basic dimension for the rear axle housing and the basic dimension engraved on the crown gear must be added to the difference dimension of the drive pinion or subtracted from it. If the engraved basic dimension is, e.g. 66.02 mm, 0.02 mm must be subtracted.
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- Determine thickness of shim on drive pinion.
Example 1:
Basic dimension of rear axle housing 66.00 mm
Dimension engraved on crown gear 66.02 mm
Deviation from basic dimension 0.02 mm
Difference dimension "C" of drive pinion 5.18 mm
Deviation from basic dimension + 0.02 mm
Production deviation of rear axle housing (Towards crown gear) + 0.06 mm
Shim to be installed 5.26 mm
Example 2:
Basic dimension of rear axle housing 66.00 mm
Dimension engraved on crown gear 65.96 mm
Deviation from basic dimension 0.04 mm
Difference dimension "C" of drive pinion 5.36 mm
Deviation from basic dimension + 0.04 mm
Production deviation of rear axle housing (Towards drive pinion) + 0.02 mm
Shim to be installed 5.42 mm
Shims are available in thicknesses from 5.00 to 5.68 mm in graduations of 0.02 mm.