2110B20 MANUAL GEARBOX (5 SPEED) WITH DIFFERENTIAL - DISMANTLE AND REBUILD - WASH AND CHECK PARTS - REPLACE SYNCHRONISERS AND INTERNAL CONTROLS IF NECESSARY - Alfa - 156 - eLearn

3239106 - 2110B20 manual gearbox (5 speed) with differential - dismantle and rebuild - wash and check parts - replace synchronisers and internal controls if necessary

) 1. Release the gearbox and differential (1a) from the hydraulic jack (1b) and the tool (1c) used for removing-refitting it from the vehicle.

	Name	Country
1c	Mount	1.870.644.001

1. Fit the gearbox and differential (1a) on the overhaul stand using the tool (1b).

Two operators are needed for this operation.

	Name	Country
1b	Mount	1.820.146.000

1. Remove the left internal differential driveshaft (1a) using tools (1b) and (1c).

	Name	Country
1b	Flange	1.820.229.000

	Name	Country
1c	Counter weight	1.821.161.000

1. Undo the bolts (1a) and remove the flanges on the differential (1b), complete with seals.2. Remove the scraper ring.

1. Undo the bolts (1a) and remove the support for the differential internal housing (1b).2. Remove the differential.3. Remove the differential bearing outer races.4. Remove the magnet.

1. Remove the bolt for the Reverse gear shaft.2. Undo the bolts (2a) and remove the gearbox casing (2b).

The gearbox casing is sealed to the bell housing: release the two parts using a wooden or resin hammer.

1. Unscrew bolts (1a) and (1b).2. Remove the 5 ^th speed control rod (2a) from the Reverse gear selector fork (2b) and the 5 ^th speed selector (2c). 3. Remove the 5 ^th speed selector fork from the control rod.

1. At the same time, remove the main shaft, layshaft, reverse shaft and 1 ^st , 2 ^nd , 3 ^rd and 4 ^th speed selector fork assemblies.

Keep the units assembled until they are placed on the workbench.

Separate the selector forks from the rods.

1. Remove the clutch release bearing fork.2. Remove the outer non-slip bush.

1. Remove the inner non-slip bush (1a) using the tools (1b) and 1c).

	Name	Country
1b	Extractor	1.820.626.000

	Name	Country
1c	Counter weight	1.840.206.001

2. Undo the bolts (2a) and remove the main shaft cover (2b).

1. Remove the main shaft rear bearing outer race (1a) using the tools (1b) and (1c).

	Name	Country
1b	Tool for Extracting/Fitting	1.870.655.000

	Name	Country
1c	Counter weight	1.840.206.001

2. Remove the main shaft adjustment shim.3. Remove the lubrication duct.

1. Remove the layshaft rear bearing outer race (1a) using the tools (1b) and (1c).

	Name	Country
1b	Tool for Extracting/Fitting	1.870.655.000

	Name	Country
1c	Counter weight	1.840.206.001

2. Remove the layshaft scraper ring.

Proceed with dismantling the layshaft, following the instructions given below.1. Check, in three places, that the gap between the gear teeth and the synchronizer ring support surfaces are within the recommended values.

In order to carry out the measurement, keep the sliding sleeve raised using a screwdriver.

If the figures do not correspond with the recommended values, during reassembly, the worn synchronizer should be replaced.

	Measurement		Value
1	Gear. teeth clearance and synchronizer ring support. surfaces. (mm)		= 0.8

1. Remove the rear bearing (1a), the 5 ^th speed driven gear (1b), the 4 ^th speed driven gear (1c) and the spacer (1d) using a hydraulic press and the plate (1e) and the half-rings (1f) using a suitable drift (1g).

	Name	Country
1e	Plate	1.820.047.002

	Name	Country
1f	Half-rings	1.870.675.000

1. Remove the 3 ^rd speed driven gear (1a) and the 2 ^nd speed driven gear (1b) using a hydraulic press, the plate (1c) and the half rings (1d).

	Name	Country
1c	Plate	1.820.047.003

	Name	Country
1d	Half-rings	1.820.046.000

1. Remove the needle bearing for the 2 ^nd speed driven gear. 2. Remove the 'triple cone' 2 ^nd speed synchronizer. 3. Remove the 1 ^st and 2 ^nd speed and Reverse gear engagement sliding sleeve (3a) with the springs (3b) and rollers (3c).

1. Remove the circlip using pliers.

When refitting, replace the circplip.

1. Remove the 1 ^st , 2 ^nd and Reverse gear sliding sleeve hub (1a), the 1 ^st speed 'triple cone' synchronizer (1b), the 1 ^st speed driven gear (1c) using a hydraulic press, the plate (1d) and the half rings (1e). 2. Remove the needle bearing for the 1 ^st speed driven gear.

	Name	Country
1d	Plate	1.820.047.003

	Name	Country
1e	Half-rings	1.820.046.000

1. Remove the circlip using pliers.

When refitting, replace the circplip.

1. Remove the front bearing (1a) using a hydraulic press, a suitable plate (1b), the reaction base (1c) with the outer race (1d) for the bearing in question on the inside.

	Name	Country
1c	Reaction base	1.870.660.000

Proceed with dismantling the main shaft, following the instructions given below.1. Check, in three places, that the gap between the gear teeth and the synchronizer ring support surfaces are within the recommended values.

In order to carry out the measurement, keep the sliding sleeve raised using a screwdriver.

If the figures do not correspond with the recommended values, during reassembly, the worn synchronizer should be replaced.

	Measurement		Value
1	Gear. teeth clearance and synchronizer ring support. surfaces. (mm)		= 0.8

1. Remove the rear bearing (1a), the retaining flange (1b), the 5 ^th speed sliding sleeve (1c), the 5 ^th speed slding sleeve hub (1d) with springs (1e) and rollers (1f), the 5 ^th speed synchronizer (1g) and the 5 ^th speed driven gear (1h) using a hydraulic press and the plate (1i) and half-rings (1l) using a suitable drift (1m).

	Name	Country
1i	Plate	1.820.047.002

	Name	Country
1I	Half-rings	1.870.676.000

1. Remove the needle bearing for the 5 ^th speed drive gear. 2. Remove the retaining ring.3. Remove the thrust rings.4. Remove the 4 ^th speed drive gear. 5. Remove the needle bearing for the 4 ^th speed drive gear. 6. Remove the spacer.7. Remove the 4 ^th speed synchronizer ring. 8. Remove the 3 ^rd and 4 ^th speed sliding sleeve (8a) with the springs (8b) and rollers (8c).

1. Remove the circlip using pliers.

When refitting, replace the circplip.

1. Remove the hub for the 3 ^rd and 4 ^th speed sliding sleeve (1a), the 3 ^rd speed 'twin cone' synchronizer (1b), the 3 ^rd speed drive gear (1c), using a hydraulic press, the plate (1d) and the half rings (1e).

	Name	Country
1d	Plate	1.820.047.002

	Name	Country
1e	Half-rings	1.870.675.000

2. Remove the needle bearing for the 3 ^rd speed drive gear.

1. Remove the front bearing (1a), using a hydraulic press, a suitable plate (1b), the support (1c) and the half rings (1d).

	Name	Country
1c	Half-rings support	1.846.017.001

	Name	Country
1d	Half-rings	1.846.001.001

Proceed with dismantling the Reverse gear shaft following the instructions given below.1. Remove the Reverse drive gear-synchronizer assembly from the Reverse gear shaft.

1. Remove the circlip using pliers.2. Remove the Reverse gear synchronizer.3. Remove the spring (3a) from the Reverse drive gear (3b).

1. Remove the O-ring.2. Remove the pin.3. Remove the needle bearing for the Reverse drive gear (3a) complete with bush (3b).4. Remove the Reverse driven gear.5. Remove the needle bearing for the Reverse driven gear.

Reassembling ( Dismantling

) Proceed with reassembling the Reverse shaft following the instructions given below.1. Fit the needle bearing for the Reverse drive gear (1a) on the Reverse shaft (1b).2. Fit the Reverse driven gear.3. Fit the needle bearing for the Reverse drive gear complete with bush.4. Fit the pin.5. Fit a new O-Ring seal.

1. Fit the spring (1a) on the Reverse drive gear (1b).2. Fit the Reverse synchronizer.3. Fit the circlip.

Fit the Reverse drive gear - Reverse synchronizer assembly on the Reverse shaft.Proceed with the reassembly of the main shaft, following the instructions given below.

Lubricate the bearings with oil before refitting them.

	Type	Component	Name	Qty.
-	Oil	GEARBOX OIL	TUTELA ZC 75 FF SEMI SYNTH	-

1. Fit the front bearing (1a), using a hydraulic press, the half plates (1b) and the fitting tool (1c).

	Name	Country
1b	Half-plates	1.820.022.000

	Name	Country
1c	Fitting tool	1.870.659.000

1. Fit the needle bearing for the 3 ^rd speed drive gear.

1. Fit the 3 ^rd speed 'twin cone' synchronizer (1a) on the hub for the 3 ^rd and 4 ^th speed sliding sleeve (1b). 2. Fit the 3 ^rd speed drive gear on the assembly constructed in the previous step.

1. Fit the assembly (1a) made up of the 3 ^rd speed drive gear complete with synchronizer and sliding sleeve, using a hydraulic press, the half plates (1b) and the fitting tool (1c).

	Name	Country
1b	Half-plates	1.820.022.000

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Fit a new circlip.2. Fit the spacer.3. Fit the needle bearing for the 4 ^th speed drive gear. 4. Fit the springs on the 3 ^rd and 4 ^th speed sliding sleeve hub. 5. Fit the 3 ^rd and 4 ^th speed sliding sleeve. 6. Fit the rollers on the 3 ^rd and 4 ^th speed sliding sleeve making sure that they fit correctly in the housings.

1. Fit the synchronizer (1a) - 4 ^th speed drive gear (1b) assembly.

Lower the 3 ^rd and 4 ^th speed sliding sleeve, engaging 3 ^rd speed. 1. Fit the thrust washers.2. Fit the retaining ring.3. Fit the needle bearing for the 5 ^th speed drive gear. 4. Fit the 5 ^th speed drive gear. 5. Fit the 5 ^th speed synchronizer.

1. Fit the 5 ^th speed sliding sleeve hub (1a) using a hydraulic press, the half plates (1b) and the fitting tool (1c).

	Name	Country
1b	Half-plates	1.820.022.000

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Fit the springs on the 5 ^th speed sliding sleeve hub. 2. Fit the 5 ^th speed sliding sleeve. 3. Fit the rollers on the 5 ^th speed sliding hub making sure that they fit correctly in the housings. 4. Fit the retaining flange.

1. Fit the rear bearing (1a), using a hydraulic press, the half plates (1b) and the fitting tool (1c).

	Name	Country
1b	Fitting tool	1.870.659.000

	Name	Country
1c	Fitting tool	1.870.659.000

Proceed with the reassembly of the layshaft, following the instructions given below.

Lubricate the bearings with oil before refitting them.

	Type	Component	Name	Qty.
-	Oil	GEARBOX OIL	TUTELA ZC 75 FF SEMI SYNTH	-

1. Fit the front bearing (1a), using a hydraulic press, a suitable plate (1b) and the fitting tool (1c).

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Using a feeler gauge, measure the housing for the front bearing circlip to be fitted.

1. Fit a new front bearing circlip.

The size of the circlip should be selected from those available as spares (1.975; 2.020; 2.065) according to the value of the housing measured previously.

2. Fit the needle bearing for the 1st speed driven gear.3. Fit the 1 ^st speed driven gear. 4. Fit the 1 ^st speed 'triple cone' synchronizer.

1. Fit the hub for the 1 ^st , 2 ^nd and Reverse sliding sleeve (1a), using a hydraulic press, a suitable plate (1b) and the fitting tool (1c).

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Fit a new circlip.2. Fit the springs on the hub for the 1 ^st , 2 ^nd and Reverse sliding sleeve. 3. Fit the 1 ^st , 2 ^nd and Reverse sliding sleeve so that the internal references correspond with the springs.

1. Fit the rollers on the 1 ^st , 2 ^nd and Reverse sliding sleeve making sure that they fit correctly in the housings. 2. Fit the needle bearing for the 2 ^nd speed driven gear.

1. Fit the 'triple cone' synchronizer (1a) on the 2 ^nd speed driven gear (1b). 2. Fit the assembly constructed as described in the previous step on the layshaft.

1. Fit the 3 ^rd speed driven gear (1a), using a hydraulic press, a suitable plate (1b) and the fitting tool (1c).

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Fit the spacer. Heat the 4 ^th speed driven gear to 120 ° C. 2. Fit the 4 ^th speed driven gear (2a), using a hydraulic press, a suitable plate (2b) and the top end of the tool (2c).

	Name	Country
2c	Tool for Extracting/Fitting	1.870.658.000

1. Fit the 5 ^th speed driven gear (1a), using a hydraulic press, a suitable plate (1b) and the top end of the tool (1c).

	Name	Country
1c	Tool for Extracting/Fitting	1.870.658.000

1. Fit the rear bearing (1a), using a hydraulic press, a suitable plate (1b) and the fitting tool (1c).

	Name	Country
1c	Fitting tool	1.870.659.000

1. Fit the inner non-slip bush (1a) for the selector fork shaft using a suitable fitting tool (1b).

'Permaglide' self-lubricated bushes should not, under any circumstances, be lubricated because the lubricant oil or grease would mix, over a period of time, with the abrasive material of the bush, forming a mixture which would increase the wear of the actual bush.

At the same time, fit the main and layshafts in their housings.If the following components are replaced:main shaftbell housing,gearbox casing,main shaft front bearing,main shaft rear bearing, hub for 5 ^th speed sliding sleeve complete layshaft,layshaft rear bearing, 3 ^rd , 4 ^th and 5 ^th speed driven gears, proceed with determining the size of the scraper rings for pre-loading the main and layshaft bearings, following the instructions given below. Thoroughly clean the support surfaces of the bearings and gearbox casing.1. Position the two gauges in the rear bearing seats in the gearbox casing.

	Name	Country
1	Gauges	1.870.648.000

1. Fit the reference crossmember on the gearbox casing.

	Name	Country
1	Reference crossmember	1.870.649.000

1. Place the two cylinders for the gauges in contact (without force) with the lower surface of the reference crossmember acting via the two special openings using a screwdriver.2. Lock the two cylinders using the bolts.

Remove the reference crossmember and the gauges from the gearbox casing.1. Fit the two gauges (1a) on the tool plate (1b).

	Name	Country
1a	Gauges	1.870.648.000

	Name	Country
1b	Mount	1.870.647.000

1. Prepare the tool for checking the bearing (1a) pre-loading with the stud bolts (1b), the spacer (1c), the disc (1d) and the centring bush (1e) designed for the 5 speed gearbox.

	Name	Country
1a	Mount	1.870.647.000

1. Match the support for determining the bearing pre-loading prepared in this way with the base plate complete with gauges.2. Connect the tool to an air line and supply a pressure of 0.5 bar so that the two actuators come into contact with the gauges.3. Fit the two dial gauges on the tool and zero them with a pre-loading of 3 mm (see reference X in the example for calculating the size of the scraper rings).

Remove the support for determining the bearing pre-loading from the base plate complete with gauges.1. Remove the disc.

1. Position the support for determining the bearing pre-loading on the gearbox casing support and fix it.2. Connect the tool to an air line and supply a pressure of 4 bar.3. Rotate the main and layshafts through ten revolutions using the tool (3a) and a suitable crank (3b).

	Name	Country
3a	Bush	1.870.652.000

Using the dial gauges, measure the differences for the layshaft and the main shaft, respectively (see reference Y in the example for calculating the size of the scraper rings).Add 0.15 mm to the difference between X and Y for the layshaft to obtain the necessary measurement for selecting the correct size of adjustment shim to be used.Subtract 0.15 mm from the difference between X and Y for the main shaft to obtain the necessary measurement for selecting the correct size of adjustment shim to be used.

Below is an example of how to calculate the size of the adjustment shims.

Reference distance X (casing)Zero the dial gauge with a 3 mm pre-loading on the checking tool.

Reference distance Y (shafts)For simplicity, let us consider that we have detected a difference of 0.9 mm, both for the layshaft and the main shaft.

Calculation of size of layshaft adjustment shim 0.15 mm should be added to the difference between X and Y; in order to understand the term 'added' better, let us imagine that the pointer will move forward by 0.15 mm i.e. 0.9 + 0.15 = 1.05 mm (size of adjustment ring).

Calculation of size of main shaft adjustment shim0.15 mm should be subtracted from the difference between X and Y; in order to understand the term 'subtracted' better, let us imagine that the pointer will move back by 0.15 mm, i.e. 0.9 - 0.10 = 0.75 mm (size of adjustment shim).

Remove the support for determining the bearing pre-loading from the gearbox support casing.1. Fit the lubrication duct.2. Fit the main shaft adjustment shim in the size calculated.3. Fit the main shaft rear bearing outer race (3a), using a hydraulic press, a suitable plate (3b) and the fitting tool (3c).

	Name	Country
3c	Fitting tool	1.870.657.000

1. Fit the layshaft adjustment shim of the size calculated.2. Fit the layshaft rear bearing outer race (2a), using a hydraulic press, a suitable plate (2b) and the fitting tool (2c).

	Name	Country
2c	Fitting tool	1.870.657.000

Fit the Reverse shaft and the 1 ^st , 2 ^nd , 3 ^rd and 4 ^th speed control rods and selector forks. 1. Lift up the Reverse driven gear and check that the Reverse shaft pin is correctly positioned.

1. Fit the 5 ^th speed selector fork on the control rod. 2. Fit the reverse selector fork (2a) and the 5 ^th speed selector (2b) on the control rod. 3. Tighten the bolts (3a) and (3b) to torque.

	Fastening	Component	Ø	Value(daNm)
3a	Bolt	5thª speed control rod	M8	2.1 - 2.6

	Fastening	Component	Ø	Value(daNm)
3b	Bolt	5thª speed selector fork	M8	2.1 - 2.6

Apply sealant to the entire matching surface of the gearbox casing.

	Type	Component	Name	Qty.
-	Sealant	GEARBOX GEAR CASING	Loctite 510	-

1. Fit the gearbox casing (1a) and fix it tightening the bolts (1b) to the recommended torque.

	Fastening	Component	Ø	Value(daNm)
1b	Bolt	GEARBOX GEAR CASING	M9	2.9 - 3.6

2. Tighten the reverse shaft bolt to torque.

	Fastening	Component	Ø	Value(daNm)
2	Bolt	Reverse shaft	M10	4.3 - 5.3

Fit the magnet.Fit the differential in its housing complete with bearing outer races.Apply sealant to the entire matching surface of the differential internal housing support.

	Type	Component	Name	Qty.
-	Sealant	GEARBOX DIFFERENTIAL MOUNT	Loctite 510	-

1. Fit the differential internal housing support (1a) and fix it tightening the bolts (1b) to the recommended torque.

	Fastening	Component	Ø	Value(daNm)
1b	Bolt	GEARBOX DIFFERENTIAL MOUNT	M10	4.3 ÷ 5.3

	Fastening	Component	Ø	Value(daNm)
1b	Bolt	GEARBOX DIFFERENTIAL MOUNT	M8	2.1 - 2.6

1. Fit the flange on the differential, gearbox side (1a), complete with a new seal and fix it tightening the bolts to the recommended torque.

	Fastening	Component	Ø	Value(daNm)
1b	Bolt	MAN G/BOX DIFF SEALING FLANGE/S	M8	2.1 - 2.6

Using a suitable drift, tighten the engine side bearing inner/outer race.1. Position the tool, complete with dial gauge, on the surface of the engine side differential and zero the dial gauge with a pre-loading of 1 mm.

	Name	Country
1	Dial gauge mounting	1.820.085.000

1. Position the tool (1a), complete with dial gauge, on the differential flange, engine side (1b) and measure the difference.

	Name	Country
1a	Dial gauge mounting	1.820.085.000

Calculate the size of the scraper ring for pre-loading the differential bearings adding 0.12 mm to the difference measured.

0.12 corresponds to the interference for bedding in and the pre-loading of the differential bearings.

1. Place in the housing the adjustment shim or shims for pre-loading the differential bearings, of the size calculated or the next size up.2. Fit the flange on the differential, engine side (2a), complete with a new seal and fix it tightening the bolts (2b) to the recommended torque.

	Fastening	Component	Ø	Value(daNm)
2b	Bolt	MAN G/BOX DIFF SEALING FLANGE/S	M8	2.1 - 2.6

3. Fit the main shaft cover (3a) and fix it using the bolts (3b).

Apply Molycote PG 21 grease to the mating surfaces between the mainshaft sealing cover and the thrust bearing.

Fit the clutch release bearing fork.Fit the outer non-slip bush.

Fit the left inner driveshaft.Undo the fixings and remove the gearbox and differential from the tool.

Two operators are needed for this operation.

	Name	Country
-	Mount	1.820.146.000

Remove the tool supporting the overhaul stand and put it back.Position the gearbox and differential on the tool used for the removing-refitting from the vehicle.

	Name	Country
-	Mount	1.870.644.001