DAF CF65, CF75, CF85 Series . Manual - part 1111

©

 200448

2-1

Inspection and adjustment

FAG

ΧΦ65/75/85 series

9

7

2. INSPECTION AND ADJUSTMENT

2.1 INSPECTION AND ADJUSTMENT, HEIGHT-CONTROL VALVE

1.

Measure the joint axle load of the leading 

rear axle and the driven rear axle.

2.

Check the DAF number of the rear axle leaf 

spring. The number is indicated on the front 

of the leaf spring.

3.

Look up the axle load ratio of the vehicle 

concerned. The axle load ratio is indicated 

on the vehicle identification plate, fitted on 

the left-hand side door post.

4.

Check the adjustment of the pressure-

limiting valve and adjust it if necessary.

5.

Check whether the bolt (A) is located in the 

lower position of the slotted hole. Check 

whether the bolt (A) is well tightened

6.

Measure the length l of the lever (B) and 

check the lever length on the basis of the 

value indicated in the table concerned, see 

"Technical data". Adjust the lever length, if 

necessary, to the length stated in the table.

7.

Fit a T-piece fitted with a test connection in 

the pipe from the pressure-relief valve to the 

air bellows.

8.

Connect a calibrated pressure gauge to the 

test connection.

9.

Measure the bellows pressure. Look up in 

the correct table, see "Technical data', the 

relevant bellows pressure at the total axle 

pressure measured and compare it with the 

bellows pressure measured.

10. If the bellows pressure has to be adjusted, 

the connection rod (C) between the lever and 

the rear axle body must be extended or 

shortened. Extending increases the pressure 

and shortening decreases the pressure.

C9 00 436

A

B

C

l
  

W9 09 002

FAG

2-2

©

 200448

Inspection and adjustment

7

ΧΦ65/75/85 series

9

11. After adjusting, operate the height-control 

valve by hand by moving the lever (B) up and 

down.

12. Let the height-control valve return to the 

initial position and check the bellows 

pressure once again. Repeat this procedure 

several times.

Note:

After the connection rod length has been 

adjusted, the axle load ratio of the steered 

leading rear axle and the driven axle 

changes will have changed in relation to one 

another. It is therefore necessary to check 

the setting of the ALR valve.

13. Check the setting of the pressure-relief 

valve.

©

 200448

2-3

Inspection and adjustment

FAG

ΧΦ65/75/85 series

9

7

2.2 INSPECTION AND ADJUSTMENT, PRESSURE-LIMITING VALVE

1.

Connect a pressure gauge to the output pipe 

(pipe connection 2).

2.

Increase and reduce the input pressure. The 

output pressure should immediately also rise 

and fall to under the set limiting pressure.

3.

Enter the input pressure and check whether 

the limiting pressure corresponds with the 

value indicated. See "Technical data".

4.

Adjust the valve by tightening or slackening 

the adjustment bolt. Tightening the adjusting 

bolt increases the pressure, slackening 

decreases the pressure.

W909003

FAG

2-4

©

 200448

Inspection and adjustment

7

ΧΦ65/75/85 series

9

2.3 INSPECTION AND ADJUSTMENT, PRESSURE-RELIEF VALVE

1.

Fit a T-piece fitted with a test connection in 

the pipe from the pressure-relief valve to the 

air bellows.

2.

Connect a pressure gauge to the test 

connection.

3.

Pressurise the bellows.

4.

Switch on the electropneumatic valve, by 

which means the bellows are vented.

5.

Check whether the residual pressure agrees 

with the value indicated, see "Technical 

data".

6.

The residual pressure can be adjusted by 

tightening or slackening the adjustment bolt 

of the pressure-relief valve. Tightening the 

adjusting bolt increases the pressure, 

slackening decreases the pressure.

Note:

If the pressure-relief valve is replaced, make 

sure that when connecting the pressure-

relief valve that it is connected in the correct 

manner. Pipe connection 2 is connected to 

the pipe from the electropneumatic valve and 

pipe connection 1 is connected to the pipe to 

the air bellows.

W909004