Page 521
1
2
3
SYNCHRONIZATION,
4 5
6
3RD GEAR
1. Lock ring
2. Synchronizing ring
3. Retaining spring, 3rd gear
4. Guide ring
5. Lock ring guide ring
6. 3rd gear
VENTILATION,
AS FROM MODEL 1978
VENTILATION
Ventilation of the transmission is by means of a hole
through the top cover in the primary gear. The hole
emerges at the centre of a plastic propeller which is
bolted to the clutch shaft.
As the clutch shaft rotates, the oil is flung away from
the hole by the propeller.
When the shaft is stationary, the oil level in the primary
gear is considerably below the hole.
With effect from transmission numbers 649792 (cars
from the latter half of 1975 model), a washer has been
installed between the vent cover and the bearing. This is
to prevent leakage occurring as a result of the oil level
having been raised in the primary gear housing.
VENTILATION,
UP TO AND INCL. MODEL 1977
SAMI
471-29A
j
Page 523
REMOVAL AND INSTALLATION
5. Remove the differential assembly. For dismantling
of the differential assembly see section 473.
5-speed transmission
Disassembling and assembling of the gear box can be done
without separating the engine and the gear box. The engine flywheel must first be removed.
DISASSEMBLING
(Proceed in the following order as far as necessary in order to remove whichever component needs attention:)
1. Clean the gearbox and drain the oil.
a) in a horizontal position
b) in a vertical position. Let the oil drain out of the
primary gear housing.
2. Remove the following covers:
front cover on the primary gear housing
side cover on the primary gear housing (there will be
some oil remaining in the primary gear housing).
Cover containing the oil filler plug.
Final drive cover.
3. Measure the backlash between the pinion and crown
wheel, see Section 473.
4. Clean off the transmission case and drain the oil.
Remove the differential bearing seat retaining
screws and remove the seat and inner driver using
6. Measure the distance of the pinion to the centre of
the crown wheel. See Section 473.
7. Remove the reverse operating lever.
#--',··,
~-1.~"''
.,,--..
tool 8390270 and extractor 8790776.
Save the spring and plunger at the shaft end of the
driver, and the shims, which will be replaced on
the condition that the differential gear backlash
has not been altered by the exchange of some components.
~
.....--
8. Engage the reverse wheel in the reverse gear position.
Place the 5th gear wheel in gear.
9. a) Free the shaft (lower sprocket) tab washer from
the input.
b) Remove the nut.
IMPORTANT
Before disassembling the transmission, always measure up the positions of the pinion gear and crown
wheel. This is to check whether there is any error in
their locations. If the pinion and crown wheel assembly is relatively new, i.e. if it has done less than 6,000
miles (10,000 km). it can be adjusted, but if the-mileage is any greater the gears will have worn themselves
into a given position. In the latter case, they should
be reassembled in the same measured positions which
they occupied before disassembly.
471-1B
Page 524
10. Remove the chain tensioner.
11. Remove the circlip from in front of the upper chainwheel bearing.
13. Remove the countershaft wheel from engagement
with the countershaft by loosening the circlip and
slide the muff against the cog wheel.
12. Remove the chainwheels and the chains simultaneously. Slide hammer 8390270 and puller 8390891
may need to be used to remove the chainwheels.
14. Remove the countershaft and reverse spindle retain-
ing plate. Use tool 8390049 to extract the countershaft so that the countershaft cog-wheel, the muff
and pressure washer can be taken out through the
side cover.
471-28
, -.._
Page 525
l
16. Remove the locking stud from the 5th speed selector fork and push the gear selector until it stops. The
fork and can then be removed.
15. Remove the screws and the oil catcher.for the input
shaft's bearing housing. Then remove the bearing
housing using slide hammer 8390270 and adapter
8790917.
17. Remove the circlip and shims from the 5th speed
synchro hub. Remove the synchro hub and then the
distance piece lying behind it from the pinion shaft.
18. Remove all primary gear housing retaining bolts and
drift in the dowels so that the primary gear housing
can be separated from the gearbox housing. (The 5th
speed selector will remain in the housing and can be
remove ·later). File away any burrs there may be
round the hole in the shaft so that the aperture in
the gear housing will not be damaged when reassemblying the primary gear to the gearbox.
471-38
Page 526
19. Remove the countershaft and the countershaft gears.
Retain the needle bearings and thrust washer for reuse.
-·-·"""' ""_a&--,._,,.--,,-,..--,----
S7406
Remove the selector shaft and the selectors (5th
and reverse on the outer shaft and 1st, 2nd, 3rd and
4th speeds on the inner). The 1st and 2nd speed
selectors should be removed together with their synchronizing unit. The reverse selector should be removed while still attached to the rev~rse selector
shaft.
21. The selector shafts should be removed from the front.
The aperture for the tapered pin should be filed so
that it is free of burrs so that the aperture is not da-
ASSEMBLING
Having removed the component that needs attention,
clean all fragments of old gaskets and all traces of old
sealing compound off the covers and mating surfaces.
Inspect the transmission case and all disassembled parts
and wash them in kerosene or similar. The parts should
be lubricated as described in the following list. Then
reassemble the transmission, following the procedure
described below:
•
maged. Remove the selector, double lockout and
spring later. Retain the selector ball and guide pin.
22. Remove the reverse spJ_,:idleand reverse wheel.
23. Remove the four screws holding the pinion shaft
bearing housing. Install tool 8790909 and press out
the pinion shaft. Keep the wheel, sleeves, washers
and shims.
471-4B
Apply Esso Nubula EP 2 grease to the following points:
1. Inner drive shaft seals and clutch shaft seal, space between seal lips.
2. Clutch shaft splines and journal in flywheel should be
lubricated (very sparingly) before assembling the engine and transmission unit.
SealingcompoundTIKATAT NO. 2 part no. (45) 3007176
should be applied to the surfaces between the primary
gear housing and the gearbox housing. Thread locking
compound (Loctite, part no. (45) 3009081) should be
applied to the following points:
1. On the 12 differential bearing seat bolts
2. On the drain plug
3. On the chain tensioner bolts
4. On the two upper countersunk bearing retainer bolts
5. On the slave cylinder housing bolts
6. On the three bolts passing through the gearbox housing cover
Page 527
NOTE. Ensure that the surfaces are dry before applying
the sealing compound.
Locking fluid (Loctite, part no. (45) 3007200) should be
applied to the following points:
1. The reverse spindle stop screw
2. The reverse gear actuator bolt
3. Hexagon screw on the reverse gear and countershaft
locking plate
Locking fluid ( Loctite, part no. (45) 3007200) should
be applied to the following points:
1. The 12 Hexagon screws on the crown wheel.
Locking fluid (Loctite, part no. (45) 3007218) should
be applied to the pinion nut.
The following parts should be lubricated with transmission oil:
1. All countershaft gear needle bearings
2. The synchro hub outer splines
3. The synchro cups
4. Running wheel end surface and pinion shaft hole
5. Gear selector lever
6. Reverse gear
7. Countershaft
8. Speedometer drive shaft
9. Differential shaft
10. Differential bearing seats Land R (O-ring)
11. Clutch shaft seal (when inserting in housing)
12. Outer drive shaft sealswhen inserting in differential
bearing retaining housings
13. Input shaft nut
The following slave cylinder parts should be lightly lubricated with Castro! UBCF 11 oil:
Inner and outer surfaces of the cylinder, cylinder housing, seal and inner surface of the piston and its end surface against the seal.
1. ,l\dJust the differential bearings to the correct compression. See section 4 73.
2. Screw the two locating studs (tool 8790438) into
the transmission case. Then shim and locate the
pinion shaft assembly. Tap the assembly gently into position, using a plastic metallet, drift 8390114
and sleeve 8390148. Then insert and tighten the
four bearing housing screws.
3. a. Before mounting the reverse gear on the pinion
shaft, the distance between the connecting surface for the primary gear housing and the pinion
shaft nut must be checked. The distance must
be 7.677"-7.681"
(195.0-195.1 mm). If it is
not this distance, shims must be placed between
the nut and the reverse gear. Shims are available
in thicknesses of 0.0118" (0.30 mm), 0.0157"
(0.40 mm) and 0.197" (0.50 mm). If the position of the pinion shaft is unchanged, the shims
used earlier can be replaced.
MEASURING THE POSITION OF THE PINION SHAFT IN
THE GEARBOX HOUSING WITH DEEP GAUGE
b. When using measuring tool 8790552, the procedure of shimming is the following:
Install the measuring tool in the gearbox housing according to fig. and measure the distance
between tool and nut with the aid of a feeler
gauge. Fit shims with a thickness equvivalent
to that of the used feeler gauge.
MEASURING THE POSITION OF THE PINION SHAFT IN
THE GEARBOX HOUSING WITH THE AID OF TOOL 8790552
4. Install the reverse gear using sleeve 8390148.
5. Fit the 1st gear on the bearing sleeve of the reverse
gear.
6. Fit 1st-2nd synchronization hub. Fit 1st-2nd gear
shift fork into 1st-2nd coupling muff and mount
these on the synchronization hub. Fit 1st-2nd gear
shift fork into 1st-2nd coupling muff and mount
these on the synchronization hub.
7. Install the 2nd gear sleeve with tool 8390148 and
mount the 2nd gear on the sleeve.
MOUNTING THE PINION SHAFT
Locating studs 8790438, drift 8390114, sleeve 8390148
SANI
471-5B
Page 528
INSTALLING
11. Ease the coupling muffs on the pinion shaft in the
neutral position and fit the gear shift shaft for 1st2nd and 3rd-4th gear shift forks.
12. Refit the reverse selector shaft with reverse operating lever. Seal the shaft stop bolt with Locite and
tighten.
13. Fit the 5th speed selector on the reverse selector
shaft.
14. Fit the needle bearing in the countershaft gear and
install in the gearbox housing.
15. Fit the countershaft and raise the countershaft gears
so they are aligned for fitting to the shaft. Insert the
shaft sufficient to hold the gears in position. The
thrust washer is to be installed later.
16. Fit the distance piece, the 5th speed synchro hub
and the locking ring on the pinion shaft. Fit the requisite shims between the hub and sleeve so that
there is no play between the parts on the pinion
shaft. The shim thicknesses available are 0.30 mm
and 0.40 mm. The locking ring on the hub and distance piece should then be removed.
THE REVERSE GEAR
Sleeve 8390148
INSTALLING
SLEEVE FOR THE THIRD GEAR
Sleeve 8390148
8. Fit the spacer, mount the sleeve for 3rd gear with
tool 8390148 and mount the 3rd gear on this sleeve.
9. Fit 3rd-4th gear synchronization hub. (Fit the synchronization hub fitted with the three locking holes
against the pinion nut.) Fit 3rd-4th gear shift fork
into 3rd-4th gear coupling muff and mount these
on the synchronization hub. Fit the bush for the
4th speed gear and fit the gear onto the bush. Install the ball bearing bush.
10. If the selector shaft has been removed, refit it together with the double lockout guide pin.
471-68
SAAB
17. Apply sealing compound, e.g. Tikatat no. 2, to the
surfaces of the primary gear casing which contact
the gasket and fit the casing to the gearbox housing.
Fit the distance piece to the pinion shaft. Fit the 5th
speed synchro hub.
Page 529
18. Fit the shims which were previously tested to the
hub so that the is no axial play once the locking
ring has been fitted.
19. Fit the 5th speed operating sleeve and selector
fork.
22. Fit the countershaft constant gear complete with
sleeve, lock ring and bearing rollers. Push the countershaft backwards so that the gear can be aligned for installation without altering the position of the thrust
washer.
23. Push the operating sleeve onto the countershaft and
insert the locking ring in its recess.
20. Fit the mainshaft together with the bearing housing,
oil catcher and connecting pipes. Use three guide
pins 8790438 for alignment and the sprocket as a
distance piece between the adapter 8790917 and
bearing housing.
Insert the bearing housing sufficient so that the
shaft meets the operating sleeve. The bearing housing should then be driven into place using the slide
hammer 8390270.
NOTE the compression of the bearing should be
checked before installation.
24. Fit the countershaft thrust washer. Extract the
countershaft and insert the washer in its position.
Then use tool 8390049 to insert the shaft so that it
locks in position.
21. Fit the thrush washer for the countershaft constant
gear. Cover the washer with grease and place it so
that the tab fits into the recess provided.
INSERTING THE INTERMEDIATE
GEAR SHAFT
Tool8390049
SUB
471-7B
Page 530
25. Fit the reverse wheel and spindle. Insert the shaft
using tool 8390049 until it locks in position.
26. Fit the locking plate and seal with Loctite.
Seal the bolts with Loctite.
27. Fit the primary gear wheel and chains. Ensure that
the hole for the tab washer on the lower primary
gear wheel is facing outwards.
28. Fit the chain tensioner. Apply sealing compound to
the bolts prior to installation.
29. Fit the nut onto the input shaft. Before torque tightening select reverse and 5th speed gears at the same
time so locking the input shaft. Then tighten the nut
to the prescribed torque and bend one of the nut
tabs into the hole provided in the gear wheel using
a round-headed drift.
471-8B
SUB
30. Fit the reverse operating lever. Seal the bolt with
Loctite.
31. Fit the differential unit. See Section 473.
32. Check the shaft seals in the bearing retaining housings and replace if necessary. Adjust the crownwheel
if necessary. See Section 473. Then fit both inner
axle shaft and inner universal joints. Ensure that the
seals are not damaged. Fit the selector ball and spring
and install the gearbox top cover assembly and gasket.
33. Fit the final drive unit cover and gasket, the primary
gear housing and chain cover with gaskets.
34. Fill with oil. See instructions on p. 430-5 "Oil filling after repairs".