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Iveco Daily Euro 4. Manual - part 90

5 S 300 TRANSMISSIONS

AILY

URO

Disassembly - assembly

. . . . . . . . . . . . . . . . . .

Mounting the transmission

. . . . . . . . . . . . . . . .

Adjusting the transmission shaft bearing
end float

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The 5 S 300 transmission is mechanical with synchronized
engagement of forward gears.

It is composed of a light alloy box (which also serves as a clutch
cover), a rear cover (where the speed engagement controls
and gearing are housed) and a control box.

There is an opening on the side of the transmission to apply
a power take-off.

Drive transmission is accomplished by a set of helical-toothed
constant mesh gears, for both forward and reverse gears.

The splined or machined gears are on four shafts: input, main,
transmission and reverse gear.

The gears splined on the main and reverse gear shafts idle on
straight roller bearings.

The input and main shafts are supported, in the transmission,
by watertight, non-adjustable ball bearings.

The transmission shaft is supported, in the transmission, by
tapered roller bearings that can be adjusted axially by means
of ring shims.

Gear engagement synchronization is accomplished by means
of free ring synchronizing devices with a single cone for 5

- 3

gears -R.G. and dual cone for 1

- 2

gears.

Control inside the transmission is accomplished with four
rods:

- a main rod to select and engage gears;

- three rods equipped with forks for engaging gears.

The external control is achieved by means of two levers:
(selection and engagement levers). The levers are actuated by
tie-rods through a transfer case, connected to the gear shift
lever located in the cab, by an assembly made up of two
flexible cables (BOWDEN cables).

The external engagement lever features two opposed
weights, used to dampen the flexible control cable
(BOWDEN) engagement thrust and, as a result, its noise.

Figure 1

108637

5 S 300 TRANSMISSIONS

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URO

1. Gear engagement lever - 2. Gear selection lever - 3. Driver - 4. Gear selection/engagement control rod -

5. Selector - 6. Driver - 7. Rod for 3

gear engagement fork - 8. Rod for 1

gear engagement fork -

9. Rod for 5

/reverse gear engagement fork.

The combined action of the selection (2) and engagement (1) levers bring about the rotation and/or axial shift of the rod (4) in two
successive stages, engaging the desired gear by means of one of the rods (9, 8 or 7).

First Stage

Depending on the angular position of the selection lever (2), the driver (3) (integral with it) turns the selector (5) with the rod (4)
(connected together), setting the selector on the rod of the chosen gear.

Second Stage
Depending on the movement given to the engagement lever (1), the driver (3) (integral with it) shifts the selector (5) (already
prepared) axially with the rod (4) and consequently also the engagement rod of the chosen gear.

SECTION A-A

This arrangement is accomplished by shifting the selection
lever (2) anticlockwise by 7.1

° to the control axis, which

corresponds to a clockwise change in the angle of the rod (4)
of 10

°.

49373

49372

Figure 2

Position of transmission in neutral and/or ready
to select 3

gear

The position of the transmission in neutral coincides with
being ready to select 3

gear.

In this case the vertical axis of the selection lever (2) is exactly
90

° from the horizontal control axis, corresponding to no

change in the angle of the rod (4).

Ready for 1

gear

Figure 3

5 S 300 TRANSMISSIONS

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This device is composed of a plate (8) and a spring (7) housed in the transmission. When passing from the 4

gear position (Figure

A) to the 5

gear position (Figure B), the driver (9), moving in the direction of the arrow, disengages the plate (8), which under the

action of the spring (7) moves onto the driver (9) preventing reverse gear from getting engaged in the opposite manoeuvre.

SECTION A-A

1. Gear engagement lever - 2. Gear selection lever -

3. Driver - 4. Gear selection/engagement control rod -

5. Selector - 6. Driver - 7. Rod for 3

gear

engagement fork - 8. Rod for 1

gear engagement fork

- 9. Rod for 5

/reverse gear engagement fork.

This device is composed of a plate (1), housed in the rear
cover, operated by the gear selection/engagement control rod
(2).

When

selecting/engaging

gear,

the

rod

(2)

simultaneously turns the plate (1) in which it is inserted. In this
way, the plate (1) will free itself from the slot of the rod
involved in engaging the gear and will lock the other two rods
by inserting itself into their slots.

Above presetting is implemented by moving selector (2)
clockwise by 7.1º with respect to control vertical axis, that
corresponds to 10º anticlockwise angular displacement of rod
(4).

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51381

Figure 4

Figure 5

Figure 6

SAFETY DEVICES

The transmission is equipped with two mechanical safety
devices:
Engagement locking device to prevent more than one gear
getting engaged at the same time.
Reverse gear anti-engagement device when passing from 5

to 4

gear.

Engagement locking device

49375

Reverse gear anti-engagement device

5 S 300 TRANSMISSIONS

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/reverse gear

Content .. 88 89 90 91 ..