Volkswagen Workshop Service and Repair Manuals

(Determining thickness of output shaft shim)

It is necessary to readjust the output shaft when

• ◆ Gearbox housing
• ◆ Clutch housing
• ◆ Output shaft

or

• ◆ Taper roller bearing

have been changed.

Adjustment overview

• ‒ → Press small taper roller bearing outer race together with a 0.75 mm thick shim fully into clutch housing.
• ‒ Insert output shaft into clutch housing and assemble gearbox housing. Tighten hexagon bolts to 25 Nm.

• ‒ → Fit measuring appliance and D.T.I. (3 mm measuring range).
• ‒ Before taking any measurements rotate output shaft to allow bearing to settle. Set D.T.I. to "O" with 1 mm preload.

Note:

This preparation is to be repeated for each subsequent measurement, otherwise the gauge will not return to the starting position.

• ‒ Pull output shaft in direction of arrow. Read off and note play indicated on D.T.I. (example: 0.30 mm).

Determining thickness of shim

The specified bearing preload is obtained by adding to the reading obtained
(0.30 mm) and the thickness of the shim installed
(0.75 mm) a preload constant of
(0.20 mm).

Example:

• ‒ → Remove output shaft and pull out small taper roller bearing outer race out of clutch housing.
• ‒ Remove inserted shim (0.75 mm thick) from clutch housing.

The following adjustment shims are available:

If the size of shim required is larger than that listed in the table, insert two shims totalling the correct figure.

• ‒ Press in small taper roller bearing outer race together with the determined shim (in example 1.25 mm) and install output shaft.
• ‒ Fit gearbox housing on and tighten hexagon bolts to 25 Nm.

Checking friction moment

→ A - Commercially available torque gauge 0 ... 600 Ncm

• ‒ Clamp clamping piece VW 548. A metal plate (or adhesive tape) must be wrapped around the output shaft to enable the clamp piece VW 548 to be clamped to the output shaft.

For new taper roller bearings the friction moment must be 80 ... 160 Ncm.

For used taper roller bearings the friction torque must be at least 30 Ncm.

Note:

Lubricate bearings with gearbox oil before checking friction moment.