DAF LF45, LF55 Series. Manual - part 455

©

 200436

1-1

Safety instructions

BRAKE SYSTEM AND COMPONENTS

ΛΦ45/55 series

6

4

1. SAFETY INSTRUCTIONS

1.1 SAFETY INSTRUCTIONS

Always observe the local safety and 

environmental regulations.

If the parking brake is deactivated 

when working on the vehicle, place 

chocks in front of and behind the 

wheels to prevent the vehicle from 

moving.

The substances and auxiliary 

substances (to be) used may 

constitute a direct or indirect health 

hazard. For that reason, always wear 

protective clothing and protective 

equipment (e.g. goggles, gloves) to 

prevent inhalation, skin contact, etc.

Use only the specified special tools. 

Parts of threaded connections have 

to be clean and free of lubricants 

before use.

Check the correct operation of the 

vehicle, and the brake system in 

particular if work has been carried 

out on it, before handing over the 

vehicle to the user.

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BRAKE SYSTEM AND COMPONENTS

1-2

©

 200436

Safety instructions

4

ΛΦ45/55 series

6

©

 200436

2-1

Inspection and adjustment

BRAKE SYSTEM AND COMPONENTS

ΛΦ45/55 series

6

4

2. INSPECTION AND ADJUSTMENT

2.1 INSPECTION, COMPRESSOR CAPACITY

1.

Bring the engine up to operating 

temperature.

2.

For a vehicle with air suspension, the 

chassis should be at the normal driving 

height.

3.

Put chocks in front of and behind the rear-

axle wheels to prevent the vehicle from 

moving.

4.

Position the parking brake in the driving 

position.

Note:

If, when draining the air reservoirs, they 

appear to hold an excessive quantity of oil, 

check the condition of the compressor and 

check the compressor for the presence of 

carbon deposits in the compressor pipes.

5.

Bleed the entire brake system.

6.

The capacity test requires that a completely 

empty system should be at operating 

pressure within 5 minutes, at an engine 

speed of 0.6 x maximum engine speed.

BRAKE SYSTEM AND COMPONENTS

2-2

©

 200436

Inspection and adjustment

4

ΛΦ45/55 series

6

2.2 INSPECTION, FOOT BRAKE VALVE

Inspection, foot brake valve
1.

Connect a pressure gauge to a brake 

chamber of the front axle (in front of the 

empty/load valve, if present).

2.

Connect a pressure gauge to the test 

connection of the load-dependent control 

valve.

3.

Pressurise the system.

4.

Depress the brake pedal a few times, 

alternately quickly and slowly, until the end 

stop is reached. Check if there is a 

discrepancy between both gauge readings 

(discrepancy maximum 0.3 

≥ 0.15 bar, at 

circuit 21 between 0 and 3 bar).

5.

If the brake pedal is gradually depressed, 

there must be no pressure jumps of more 

than 0.3 

≥ 0.15 bar in either circuit, at circuit 

21 between 0 and 3 bar.

6.

When the foot brake valve is completely 

depressed, the reading of both gauges 

should indicate the max. output pressure.

See "Technical data".

7.

When the brake pedal is not depressed, the 

pressure gauges should not indicate any 

pressure.