Volkswagen Workshop Service and Repair Manuals

Adjusting reverse gear brake -B1-

Special tools and workshop equipment required

t	Support plate -VW 309-

t	Support clamp -VW 313-

t	Gearbox support -VW 353-

t	Thrust plate -VW 402-

t	Depth gauge

t	Straightedge

t	Feeler gauge

Overview - components for adjusting reverse gear brake -B1-

1 -	Gearbox housing

q	With input gear and planet carrier installed.

2 -

Shim

q	1 or 2 shims may be installed.

3 -	Outer plate -B1-

q	Quantity → Chapter.

4 -	Inner plate -B1-

q	Quantity → Chapter.

5 -	Thrust plate

q	Install with flat side facing plates.

q	Parts are allocated according to gearbox code letters.

6 -	Dished spring

q	Convex side faces freewheel.

7 -	Freewheel with -B1- piston

Before removing or installing freewheel, remove → valve body, take out plug → Chapter and remove gearbox speed sensor -G38- → Item.

8 -	Retaining ring

Determining thickness of shim -B- –  Observe general repair instructions → Chapter. Shim thickness depends on gap “x” and is to be selected from table → . X = K + l 2 - m A -  Shim X -  Gap l -  Position of piston in freewheel m -  Height of plate set including pressure plate K -  Constant value = 26.9 mm “K” is determined by structural height in gearbox housing and is not adjustable. Calculating I:

–  Press piston in direction of arrow to stop. –  Place straightedge -A- on outer race of freewheel. –  Measure to inner edge of piston with depth gauge -B-. Example:

Measured value	=	51.8 mm
- Straightedge	=	-48.2 mm
Determined value of l	=	3.6 mm

Determining m:

–  Place straightedge -A- on thrust plate. –  Press set of plates including pressure plate together in direction of arrow and measure thickness of plate set with depth gauge -B-. Example:

Measured value	=	73.5 mm
- Straightedge	=	-48.2 mm
Determined value m	=	25.3 mm

X = K + l 2 - m = 26.9 + 3.6 2 - 25.3 = 3.4 mm –  Determine size of shim according to table: Table of shims:

Gap-x- (mm)	Shims (mm)
2.36 … 2.45 2.46 … 2.55 2.56 … 2.65	1.0 1.1 1.2
2.66 … 2.75 2.76 … 2.85 2.86 … 2.95	1.3 1.4 1.5
2.96 … 3.05 3.06 … 3.15 3.16 … 3.25	1.6 1.7 1.8
3.26 … 3.35 3.36 … 3.45 3.46 … 3.55	1.9 1.0 + 1.0 1.0 + 1.1
3.56 … 3.65 3.66 … 3.75 3.76 … 3.85	1.1 + 1.1 1.1 + 1.2 1.2 + 1.2
3.86 … 3.95 3.96 … 4.05 4.06 … 4.15	1.2 + 1.3 1.3 + 1.3 1.3 + 1.4
4.16 … 4.25	1.4 + 1.4

–  Ascertain thickness of shim according to table and determine part No. from parts catalogue. Example: Value 3.4 mm = insert two 1.0 mm thick shims. –  After determining shim for -B1-, check dimensions. Checking dimensions for reverse gear brake -B1- –  Install parts up to freewheel and secure with retaining ring ⇒ Assembling planetary gearbox → Chapter.

–  Measure play between plates with feeler gauge “A”. Play: min. = 1.25 mm max. = 1.55 mm