DAF CF65, CF75, CF85 Series . Manual — part 1158

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200423

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Inspection and adjustment

EXPLANATORY NOTES ON THE MAINTENANCE ACTIVITIES

ΧΦ75 series

5

3.21 INSPECTING THE COMPRESSOR LINE

Remain at a safe distance from

rotating and/or moving components.

Note:

If excessive values are measured, the inside of

the air-dryer housing and the silencer on the vent

should first be cleaned. Then repeat the

inspection.

1.

Bring the engine up to operating

temperature.

2.

Bleed the system to a pressure below the

cut-in pressure of the pressure regulator.

3.

Remove compressor control line (1) which is

hooked up to connection point 23 of the air

dryer. Then seal the opening at connection

point 23.

4.

Build up pressure in the brake system

(pressure regulator must cut out).

5.

When the engine is not running, remove the

safety valve from the compressor line and

replace it with a test nipple.

6.

Connect a pressure gauge (measuring range

0-16 bar) to the test nipple.

7.

Start the engine and run it at maximum

speed.

}

R600521

1

EXPLANATORY NOTES ON THE MAINTENANCE ACTIVITIES

3-16

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200423

Inspection and adjustment

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ΧΦ75 series

8.

The pressure gauge should indicate a

pressure below 2 bar with the pressure

regulator switched off. If the measured

pressure exceeds the value indicated, the

compressor line should be cleaned or

replaced.

Note:

If the pressure measured is too high, there is

excessive carbon deposit in the compressor

line. This may be due to the poor condition of

the compressor (oil consumption).

9.

Run the engine at idling speed.

10. Bleed the brake system until the cut-in

pressure of the pressure regulator has been

reached and switch off the engine. The

needle of the pressure gauge may not drop

too quickly now. If necessary, check the

system for air leakage. Pay particular

attention to the compressor line and

compressor.

11. Fit the safety valve.

12. Connect the compressor control line to

connection point 23 of the air dryer.

R600249

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200423

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Inspection and adjustment

EXPLANATORY NOTES ON THE MAINTENANCE ACTIVITIES

ΧΦ75 series

5

3.22 CHECKING THE BRAKE COMPONENTS AND BRAKE SYSTEM FOR LEAKS

1.

While operating the service brake, check

whether any leaks occur in the brake system.

If the brake system of a vehicle has been

charged to the maximum pressure, it should

generally be possible to drive the vehicle

after a period of 16 hours of uninterrupted

standstill, without having to first charge the

brake system to adequate operating

pressure. This implies a maximum pressure

drop of approx. 0.4 bar per hour at normal

system pressure.

Note:

Always connect auxiliary consumers and

accessories to circuit 4.

EXPLANATORY NOTES ON THE MAINTENANCE ACTIVITIES

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200423

Inspection and adjustment

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ΧΦ75 series

3.23 INSPECTING THE AUTOMATIC BRAKE ADJUSTER

Brake drum

Inspection, brake adjuster travel
1.

Measure the basic setting L1.

2.

Measure the position when the brakes are

applied, L2 (minimum brake system

pressure 6 bar).

3.

Calculate the brake stroke L3 = L2 - L1, see

"Technical data". If the brake stroke differs

from the specified value, take the following

action:

4.

Check whether the control plate (1) is locked

in respect of the fixed bracket.

5.

If not, turn the control plate as far as possible

(until the internal stop is felt) in the direction

in which the brake adjuster is moved during

braking.

6.

Fix the control plate in this position using the

attachment nut on the fixed bracket.

7.

Check the internal slip using a torque

wrench.

Inspection, internal slip
1.

Make certain that there is sufficient pressure

in the reservoirs (6.5 bar minimum).

2.

Release the parking brake.

3.

Fit a torque wrench on the hexagonal

adjusting bolt and turn this counter-

clockwise. For the permitted value, see

"Technical data".

If the specified reverse torque is not

reached, but the worm shaft already turns at

a lower value, the brake adjuster should be

replaced.

M6101

L2

L1

M6005

1