SEAT Workshop Service and Repair Manuals

Primary shaft: dismounting and assembly

t	If new pinions have to be fitted, consult the Identification Initials section, group assignment, reductions, filling capacities → Chapter.

t	The primary shaft must always be adjusted when any component affecting the position of the tapered bearing bushes has been replaced → Chapter.

1 -	Securing screw for the 5th gear pinion, 40 Nm

2 -	Disc spring

q	The concave side must face the 5th gear pinion.

3 -	5th gear pinion

q	Dismounting and assembly → Anchor

4 -	Outer track, tapered roller bearing

q	Dismounting → Fig.

q	Assembly → Fig.

5 -	Tapered roller bearing

q	Dismounting → Fig.

q	Assembly → Fig.

6 -	Gearbox casing

7 -	Primary shaft

q	If being replaced, the primary shaft should be adjusted.

q	Adjustment of the primary shaft → Chapter

8 -	Needle bearing

q	Oil well before assembling.

9 -	3rd gear pinion

q	Dismounting → Fig.

q	Assembly → Fig.

q	Assemble together with the sliding sleeve and the synchroniser bush for 3rd and 4th gears.

10 -	Synchroniser bush 3rd gear

q	Checking for wear → Fig.

11 -	Guard ring

q	Detachment → Fig.

q	Attachment → Fig.

12 -	Synchroniser unit for 3rd and 4th gears

q	The parts come in pairs.

q	Detachment → Fig.

q	Assembly → Fig. and → Fig.

q	Assembly on the primary shaft → Fig.

13 -	Guard ring

q	Detachment → Fig.

q	Attachment → Fig.

14 -	4th gear synchroniser bush

q	Checking for wear → Fig.

15 -	4th gear pinion

16 -	Needle bearing

q	Impregnate with gear oil before assembling

17 -	Retainer washer

18 -	Tapered roller bearing

q	Can be detached and assembled without using tools

19 -	Adjusting washer

q	For the primary shaft

q	Calculate the thickness → Chapter

20 -	Outer track, tapered roller bearing

q	Detachment → Fig.

q	Assembly → Fig.

21 -	Clutch casing

22 -

Spring

q	Assembly position → Fig.

23 -

Cotters

24 -	Sliding sleeve

25 -	Synchroniser bush

q	Bush identification → Fig.

26 -

Spring

q	Assembly position → Fig.

Special tools and workshop equipment required

t	Replacement parts extractors case -U-40100-

t	Replacement parts repair case -U-40200-

t	Pliers for opening spring rings -A-81124-

t	Electrical blower -SAT 1416-

t	Universal tester stand -T20020-

Detaching the outer track of the tapered roller bearing –  Using tool -U-40200/20-, detach the outer track of the tapered roller bearing on the primary shaft from the gearbox casing.   Note! A 1 mm. thick washer is attached between the outer track of the tapered roller bearing and the gearbox casing.

Assembling the outer track of the tapered roller bearing –  Using tool -U-40200/10- and tool -U-40200/11-, attach the outer track of the tapered roller bearing to the gearbox casing.   Note! Attach the 1 mm. thick washer between the outer track of the tapered roller bearing and the gearbox casing beforehand.

Detaching the tapered roller bearing –  Attach tool -U-40100/4- between the bearing and the primary shaft pinion. –  Set the primary shaft -with tool -U-40100/4- attached- in a press and take out the bearing.

Assembling the tapered roller bearing –  Attach tool -U-40100/3- under the primary shaft pinion. –  Fit the bearing with tool -U-40200/15- by using a press.

Detaching the outer track of the tapered roller bearing –  Using tool -U-40100/2-, take the outer track of the primary shaft tapered roller bearing off the clutch casing.

Assembling the outer track of the tapered roller bearing –  Using tool -U-40200/11- and tool -U-40200/10-, assemble the outer track of the tapered roller bearing of the primary shaft onto the clutch casing.

Detaching the guard ring –  Use tool -U-40200/26-.   Caution The guard ring may forcefully spring off during dismounting. Prevent this from happening by placing a cloth or a protective screen behind the primary shaft. Beware of accidents!

Removing the 3rd gear pinion and the 3rd and 4th gear synchroniser unit The 3rd gear pinion is detached together with the 3rd and 4th gear synchroniser unit. –  Detach the guard ring beforehand. –  Put tool -U-40100/3- on the primary shaft below the 3rd gear pinion. –  Set the primary shaft -with tool -U-40100/3- attached- in a press and take off the 3rd gear pinion together with the 3rd and 4th gear synchroniser unit.

Assembling the guard ring   Note! Tool -A-81124- can also be used.

Checking for wear on the synchroniser ring Make sure not to mix up the synchroniser rings from the different pinions. –  Before checking for wear, thoroughly clean the synchroniser rings and their corresponding pinions. –  Attach the synchroniser ring to the corresponding pinion. Squeeze the synchroniser ring onto the pinion and measure the height “a” with a gauge.

Synchroniser ring	Measurement “a” in new synchroniser	Limit of wear
3rd and 4th gear	1,1…1,7 mm	0,5 mm

Assembling the sliding sleeve and the synchroniser bush for 3rd and 4th gears The 3rd and 4th gear synchroniser bush is identified by a neck -bottom arrow-. Assembly position: The longer teeth of the synchroniser bush and the identification neck must face the 4th gear pinion. The upper notch -top arrow- must face 3rd gear.

Assembling the sliding sleeve and the synchroniser bush –  The sliding sleeve is assembled by pushing it on the synchroniser bush. –  Insert the cotters and attach the springs, with an offset of 120º between them. –  The hooked end of each springs must fit into the corresponding cotter.

Assembling the 3rd and 4th gear synchroniser unit –  Attach tool -U-40100/3- to the primary shaft below the 2nd gear pinion. –  Heat the synchroniser bush to around 100º with the electrical blower -SAT 1416-. –  Set the primary shaft - with tool -U-40100/3- installed - in a press. –  Attach tool -U-40200/20- onto the 3rd and 4th gear synchroniser unit and fix it as far as it will go. –  The synchroniser unit cotters must coincide with the bush housings. –  Fit a new guard ring and making sure that it sits perfectly in its housing.