Layshaft: dismantling and assembling

Make

SEAT

Model

Leon Mk1

Section

02J 5-speed manual gearbox › Gearbox,mechanics,gears,shafts,internal operation › Layshaft: dismantling and assembling

Power transmissionLayshaft: dismantling and assembling

Layshaft: dismantling and assembling

Special tools and workshop equipment required

t	Gearbox extractor set -U-40100-

t	Gearbox repair set -U-40200-

t	Gearbox repair set -U-40300-

t	Circlip opening pliers -A-81124-

  Note!

t	Whenever new gears or a new layshaft are fitted consult the technical data → Chapter, Code letters, group numbers, ratios, filling quantities.

t	If the layshaft or the roller bearings are replaced, the layshaft must be adjusted → Chapter.

t	The layshaft must be adjusted whenever elements have been replaced which could affect the position of the roller bearings. Refer to Adjustment chart → Chapter.

1 -	Hexagon nut

q	25 Nm + 90°

q

4 units

q	To secure the bearing housing

2 -	Clutch housing

q	Repairing → Chapter

3 -

Shim

q	For the layshaft

q	Determine thickness → Chapter, Layshaft: adjusting

4 -	Outer track, roller bearings

q	Remove → Fig.

q	Fit → Fig.

5 -	Small roller bearing

q	Remove → Fig.

q	Fit → Fig.

6 -

Layshaft

q	A matched pair with the driveshaft gear; they must be replaced together

q	In case of replacement → Chapter, Code letters, group numbers, ratios, filling quantities

q	Adjusting → Chapter

7 -	Large roller bearing

q	Remove → Fig.

q	Fit → Fig.

8 -

O-ring

q

4 units

q	Always renew

q	For the securing bolts of the bearing housing → Item

9 -	Bearing housing

q	With outer track of the large roller bearing → Item

q	The external track should only be replaced together with the large roller bearing and the bearing housing

10 -	Stop washer

q	The step of the shim should be facing the roller bearing

11 -	Sliding 1st gear

q	Before fitting the 1st gear, fit the stop washer → Item

12 -	Needle roller bearing

q	For the sliding 1st gear

13 -	Synchronised ring for 1st gear

q	Identification → Fig. and → Fig.

q	Checking for wear → Fig.

q	Check that the tabs show no signs of wear

14 -	Syncromesh assembly for 1st and 2nd gear

q	Remove → Fig.

q	Dismantling → Fig.

q	Assembling the components → Fig. and → Fig.

q	Installation position → Fig.

q	Fit → Fig.

15 -	Safety ring

q	Use tool -A-81124- to remove the circlip

q	Always renew

16 -	External syncromesh ring 2nd gear

q	Identification → Fig. and → Fig.

q	Checking for wear → Fig.

q	Assembly position: The cut-outs of the syncromesh ring must fit with the locking keys in the 1st and 2nd gear syncromesh assembly → Item

17 -	Intermediate syncromesh ring 2nd gear

q	Place in the external syncromesh ring 2nd → Item

q	Installation position → Fig.

q	Replace if it shows signs of wear or grooves

18 -	Internal syncromesh ring 2nd gear

q	Identification → Fig. and → Fig.

q	Checking for wear → Fig.

q	Check that the tabs show no signs of wear

q	Installation position → Fig.

19 -	Sliding 2nd gear

q	Installation position → Fig.

20 -	Needle roller bearing

q	For sliding 2nd gear

21 -	Stop washer

22 -	Needle bearing bush

q	Remove together with sliding 2nd gear → Fig.

q	Fit → Fig.

23 -	Needle roller bearing

q	For sliding 3rd gear

24 -	Sliding 3rd gear

25 -	Syncromesh ring 3rd gear

q	Checking for wear → Fig.

26 -	3rd and 4th syncromesh assembly

q	Remove → Fig.

q	Dismantling → Fig.

q	Assemble → Fig. and → Fig.

q	Installation position → Fig.

q	Fit → Fig.

27 -	Needle bearing bush

q	Remove together with the synchromesh 3rd and 4th gear assembly → Item

q	Fit → Fig.

28 -	Needle roller bearing

q	For sliding 4th gear

29 -	Syncromesh ring for 4th gear

q	Checking for wear → Fig.

30 -	Sliding 4th gear

31 -	Stop washer

32 -	Needle roller bearing

q	For layshaft

q	Removing and fitting → Chapter, Gearbox casing and clutch casing: repairing

33 -	Gearbox casing

34 -	Needle bearing bush

q	Remove → Fig.

q	Fit → Fig.

35 -	Sliding 5th gear

q	Removing and fitting → Chapter, Gearbox casing and 5th gear cover removing and installing

36 -	Plate spring

q	Assembly position: the concave side should be facing the sliding 5th gear

37 -	Securing screw for sliding 5th gear

q	The screw head incorporates a housing for the plate spring → Item

q	Assembly → Chapter,Gearbox casing and 5th gear cover removing and installing

Remove the outer track of the small roller bearing –  Fit claws -40300/17- on tool -U-40300/16- using their securing screws. –  Fit the tool assembly on the lower part of the outer track of the clutch housing roller bearing expand tool -U-40300/16- with screw -1-. –  Place the extractor -U-40300/15- on the clutch casing and screw the extractor shaft on tool -U-40300/16-. –  Turn nut -2- until the small clutch housing roller bearing is extracted.

Fit the outer track of the small roller bearing

Removing the small roller bearing –  Put the layshaft in a vice with protected jaws -A-, so that the 4th gear is facing the vice screw. –  Place tool -T20022/48- under the roller bearing and tighten hard.

Fitting the small roller bearing –  Fit tool -U-40100/3- under the 4th gear and locate tool -U-40200/19- side A facing the small roller bearing.

Remove the needle bearing bush, the 4th gear, the 3rd and 4th synchromesh assembly, the 3rd gear, and the 2nd gear from the layshaf –  Fit tool -U-40100/3- under the 2nd gear and locate tool -U-40300/2- side A as shown in the drawing.

Remove the needle bearing bush, the 1st and 2nd synchromesh assembly, and the 1st gear from the layshaft –  Remove the safety ring with tool -A-81124- before removing the components.

Removing the large roller bearing

Fitting the large roller bearing Assembly position: The roller bearing side with the smaller diameter must face tool -U-40200/18-.

Check wear of 1st, 3rd, and 4th gear synchromesh rings –  Before checking for wear, thoroughly clean the syncromesh rings and their corresponding gears. –  Place synchromesh ring on the corresponding gear cone. press the synchromesh ring onto the gear and measure dimension “a” with a feeler gauge.

Syncromesh ring	Measurement “a” on a new syncromesh	Wear limit
1st gear 3rd gear 4th gear	1.0 ... 1.7 mm	0.5 mm

Removing the 1st and 2nd gear syncromesh assembly –  To remove the 1st and 2nd gear syncromesh assembly, withdraw the springs -1- and move the sliding sleeve -2- fully upwards. Fit the 1st and 2nd gear syncromesh assembly as follows. –  Place the sliding sleeve -2- on the syncromesh hub -3- so that the the recesses of the syncromesh ring locking keys -4- of both components coincide. Assembly position: Fit the sliding sleeve on its hub so that when assembled they are in such a position that the wider collar of the syncromesh hub - arrow A- and the external teething of the movable -arrow B- are facing in opposite directions.

Assembling the 1st and 2nd gear syncromesh assembly –  The sliding sleeve must be fitted by pushing it onto the syncromesh hub. –  Insert the locking keys and fit the springs at 120° from each other. The angled ends of the springs must be inside the locking keys.

Fitting position of the syncromesh assembly for 1st and 2nd gears –  The teeth -arrow 1- of the sliding sleeve must face the teething -A- for housing of the 3rd and 4th gear synchromesh assembly. –  The collar -arrow 2- of the synchromesh hub must be facing the 1st gear -B-.

Fitting the syncromesh assembly for 1st and 2nd gears on the layshaft –  Place the 1st gear synchromesh ring on the 1st gear. –  Locate tool -U-40100/3- with tool -U-40200/19- with side A facing the roller bearings. –  Turn syncromesh gear so that the cut-outs coincide with the locking keys. –  After fitting the synchromesh assembly, fit the safety ring with using tool -A-81124- → Item.

Identification of the 1st and 2nd gear synchromesh rings –  Syncromesh ring 1st gear 3 teeth ground down to half -arrow-. –  Syncromesh ring 2nd gear 2 or 3 teeth ground down to half -arrow-. –  The 2nd gear synchromesh ring is only supplied as a spare, with2 teeth ground down to half.

Identification of the 1st and 2nd gear synchromesh rings –  Syncromesh ring 2nd gear: 3 recesses -arrows- –  Syncromesh ring 1st gear: without recesses

Checking wear for 2nd gear external synchromesh ring –  Before checking for wear, thoroughly clean the syncromesh rings and their corresponding gears. –  Place synchromesh ring on the corresponding gear cone press the synchromesh ring onto the gear and measure dimension “a” with a feeler gauge.

Syncromesh ring	Measurement “a” on a new syncromesh	Wear limit
2nd gear	1.2 ... 1.8 mm	0.5 mm

Assembly position of the 2nd gear intermediate ring –  The points -arrows- must face the 1st gear -A-.

Checking wear for 2nd gear internal synchromesh ring –  Before checking for wear, thoroughly clean the syncromesh rings and their corresponding gears. –  Place synchromesh ring on the corresponding gear cone. press the synchromesh ring onto the gear and measure dimension “a” with a feeler gauge.

Syncromesh ring	Measurement “a” on a new syncromesh	Wear limit
2nd gear	0.75 ... 1.25 mm	0.3 mm

Assembly position of the 2nd gear internal ring –  The points -arrows 1- of the 2nd gear internal ring -A- must be housed in the recesses -arrows 2- of the synchromesh ring -B-.

Assembly position of the 2nd gear –  The 2nd gear collar -A- must face the 1st gear -B-. –  The recesses -arrows- of the 2nd gear -A- must fit into the lugs of the intermediate synchromesh ring → Fig..

Fit the 3rd gear needle bearing bush –  Position the 2nd gear needle bearing and the stop washer. –  Locate tool -U-40100/3- with tool -U-40200/19- with side A facing the roller bearings. –  Place tool -U-40300/8- with side A facing the bush and tool -U-40300/9- between the press and tool -U-40300/8-.

Removing the 3rd and 4th gear syncromesh assembly –  To remove the 3rd and 4th gear syncromesh assembly, withdraw the springs -1- and move the sliding sleeve fully upwards -3-. Fit the 3rd and 4th gear syncromesh assembly as follows. –  Place the sliding sleeve -3- on the synchromesh hub -4- so that the recesses for housing the blocking keys -2- of both components coincide.

Assembling the syncromesh assembly for 3rd and 4th gears –  The sliding sleeve must be fitted by pushing it onto the syncromesh hub. –  Insert the locking keys and fit the springs at 120° from each other. The angled ends of the springs must be inside the locking keys.

Fitting position of the syncromesh assembly for 3rd and 4th gears –  The bevelled collar -arrow- of the synchromesh hub must be facing the 4th gear.

Fitting the syncromesh assembly for 3rd and 4th gears on the layshaft –  Locate tool -U-40100/3- with tool -U-40200/19- with side A facing the roller bearings. –  Turn syncromesh gear so that the cut-outs coincide with the locking keys.

Fit the 4th gear needle bearing bush –  Locate tool -U-40100/3- with tool -U-40200/19- with side A facing the roller bearings. –  Place tool -U-40300/8- with side A facing the bush and tool -U-40300/9- between the press and tool -U-40300/8-.

Fit the layshaft needle bearing bush –  Before fitting the needle bearing bush, fit the stop washer. –  Locate tool -U-40300/3- with tool -U-40200/19- with side A facing the roller bearings. –  Locate tool -U-40300/8- with side A facing the bush.

01 Transmission

The same page in: Leon Mk2.