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Left Flange Shaft Ball Bearing Pretension, Checking






Left Flange Shaft Ball Bearing Pretension, Checking

=> [ Pretension on Ball Bearing, Optimizing, Left Flange Shaft ]

=> [ Pretension on Ball Bearing, Adjusting, Left Flange Shaft ]

Check the ball bearing pretension using the wear pattern on the bearing bracket - arrow -.






The pretension on the left flange shaft ball bearing must be checked only on certain vehicles. Refer to the table for a list of the vehicles Left Flange Shaft.

This is not necessary on vehicles built later because they have been redesigned.

=> [ Left Flange Shaft ] Left Flange Shaft

Wear Pattern"A"






Small indentations near the hole on the bearing bracket - arrows -.

No trace of wear or material erosion.

- Optimize the pretension on the ball bearing for the left flange shaft. Refer to => [ Pretension on Ball Bearing, Optimizing, Left Flange Shaft ].

Wear Pattern "B"






Traces of wear, if necessary, with material erosion all around the hole on the bearing bracket - arrow -.

- Adjust the pretension on the left flange shaft bearing. Refer to => [ Pretension on Ball Bearing, Adjusting, Left Flange Shaft ].

- Replace the bearing bracket, the ball bearing and the circlip. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket.

Pretension on Ball Bearing, Optimizing, Left Flange Shaft

The pretension on the left flange shaft ball bearing must be optimized only on certain vehicles. Refer to the table for a list of the vehicles Left Flange Shaft.

This is not necessary on vehicles built later because they have been redesigned.

Procedure

Left flange shaft removed, refer to => [ Left Flange Shaft ] Left Flange Shaft.

Conditions for optimizing:






The bearing bracket does not show any traces of wear or material erosion.

Small indentations near the hole on the bearing bracket - arrows - are permissible.

Bearing bracket with wear pattern "A" (the bearing bracket does not shown any traces of wear or material erosion).






A shim is inserted into the bearing seat on the transmission to optimize the pretension on the ball bearing.

- Insert a shim (0B4 409 227) - 1 - into the bearing seat on the transmission before installing the flange shaft to improve the pretension.






- Install the left flange shaft => [ Installing ] Left Flange Shaft.

Pretension on Ball Bearing, Adjusting, Left Flange Shaft

Special tools, testers and auxiliary items required

Straight Edge 500 mm (VAS 6075)

The pretension on the left flange shaft ball bearing must be optimized only on certain vehicles. Refer to the table for a list of the vehicles Left Flange Shaft.

This is not necessary on vehicles built later because they have been redesigned.

Left flange shaft removed, refer to => [ Left Flange Shaft ] Left Flange Shaft.

Bearing bracket with wear pattern "B" (traces of wear if necessary with material erosion all around the hole).






The bearing bracket and ball bearing must be replaced. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket.

Procedure






- Clean off any dirt and corrosion from the contact surface - arrow - using 150 grain sand paper.

It is not necessary to sand the contact surfaces all the way down to bare metal. It is enough to just remove any dirt and corrosion.

- Clean the contact surface and bearing seat.

- Install the new left flange shaft ball bearing - arrow - into the bearing seat.






Next procedure:

By bearing oversize (the bearing sticks out slightly above the contact surface).

With bearing undersize (the bearing sits deeper than the contact surface).

Procedure if there is Bearing Oversize






- Place (VAS 6075) straight across the bearing and determine the distance to the contact surface on the transmission housing on both sides with the feeler gauge.

- Write down the measured value.

- Place the straight edge 90° offset across the bearing and determine the distance to the contact surface on the transmission housing on both sides with the feeler gauge.

- Write down the measured value.

Selecting the Shim(s):

Use the smallest value take from the four values to select the shim(s).

Specified value, bearing oversize = 0.5 to 0.8 mm






Example:

1 shim:

0.1 mm + 0.3 mm = 0.4 mm, "bearing pre-load is too small"

2 shims:

0.1 mm + 0.3 mm + 0.3 mm = 0.7 mm, "bearing pre-load is in the specified range"

Result: Insert two 0.3 mm shims to reach the bearing pre-load = 0.7 mm within the 0.5 to 0.8 mm specified value.

Procedure if there is Bearing Undersize






The bearing under size can only be determined in the described procedure.

- Place (VAS 6075) straight across the contact surface on the transmission housing and measure the distance to the bearing on both sides with a feeler gauge.

- Write down the measured value.

- Place straight edge 50 mm offset across the contact surface on the transmission housing and measure the distance to the bearing on both sides with a feeler gauge.

- Write down the measured value.

Selecting the Shim(s):

Use the largest value taken from the four values to select the shim(s).

Enter the measured bearing under size as negative value ("-") into the calculation.

Specified value, bearing oversize = 0.5 to 0.8 mm






Example:

1 shim:

-0.15 mm + 0.3 mm = 0,15 mm, "bearing preload is too small"

3 shims:

-0.15 mm + 0.3 mm + 0.3 mm + 0.3 mm = 0.75 mm, "bearing pre-load is in the specified range"

Result: A 0.75 mm bearing preload within the specified value of 0.5 to 0.8 mm is reached by installing three 0.3 mm shims.

Continuation for All






- Replace the bearing bracket, the ball bearing and the circlip. Refer to => [ Left Flange Shaft Ball Bearing Mounting Bracket ] Left Flange Shaft Ball Bearing Mounting Bracket.

- Insert the determined number of shims (0B4 409 227) - 1 - into the bearing seat on the transmission before installing the flange shaft.

- Install the left flange shaft => [ Installing ] Left Flange Shaft.