Readjust parking brake

AP42.20-B-4261A

Readjust parking brake

12.02.16



Removal

Checking and adjusting the brake shoes

Danger!

Important information and preliminary measures

Recommended requirements are always to be followed, of personal safety to prevent accidents, as well as of environment protection.



Refer to: General information on parking brake

AH42.20-B-0001-01A

Brake linings and brake shoes are assembled by the manufacturer. Brake shoe and brake linings are supplied as a single part

 To carry out the parking brake adjustment a device is utilized that permits the brake shoes to be adjusted to a standard diameter “D”. Therefore, after assembly and before installing the brake drum or carrying out the adjustment, the brake shoes have to be adjusted with the device.

*BE42.20-B-1009-01C



Position the shifter in neutral

1

Place the vehicle on flat and level ground that permits working safely. Chock the front wheels to prevent unintentional vehicle rolling

 This in the case of not having an appropriate elevator or pit.

2

Turn off the master switch

We also recommend to detach the battery leads

 As this is about electronic vehicles, always follow the recommendations for this type of vehicle.

3

Lift the vehicle safely so the rear wheels clear the ground in order to be able to turn the differential and the drum brake

 It is not permissible to lift nor to support the vehicle by the center of the differential.

Danger!

Danger when leaving detached from the parking brake drum, the transmission shaft at the rear universal joint

Danger of serious personal and material accidents.

 With the transmission shaft detached, if the engine is started accidentally and the gearbox is shifted or is being shifted, serious vehicle damages will occur and the transmission shaft will be irreparably damaged.

AS00.00-B-0005-01A

AS00.00-B-0004-01A

Attention!

Care with the balancing

Observe the recommended care to maintain the balance of the transmission shaft and its appendices.

4

Mark the position of the rear universal joint flange on the brake drum to maintain the balance of the transmission shaft assembly, of the drum (1) and of the flange (3)

 The brake drum (1) is positioned by the bolt (6), maintaining always the same position in relation to the revolutions transmission flange.

5

Remove the bolts (2) and loosen the transmission shaft with the flange and the universal joint. Move the transmission shaft aside and protect the universal joint

 The transmission shaft is balanced as an assembly, therefore it is not to be detached at the splines in the front part.

If by any circumstances it needs to be detached at the splines, mark beforehand the original position to be assembled again in the very same position. In case of doubts about the original position, it will have to be balanced before installing.

6

Confirm that the parking brake lever in the cab is fully released at the ratchet

Remove the bolt (6) that works as a guide of the brake drum (1)

Remove the brake drum (1)

Should it be necessary, clean the brake linings with fine sandpaper and apply light jets of compressed air so the assembly is clean of debris

7

Install the adjustment device on the brake shoes and adjust shoes on the adjustment bolt turning the crown (4) until the brake linings (5) are completely propped

 In this position, when being adjusted in the device, the new linings on the shoes (5) will be at standard diameter “C” in order to be able to adjust the traction cables.

*BE42.20-B-1008-01C



Installing

8

Remove the adjusting device, install the brake drum (1) and fasten it on the flange with the bolts (6)

 In the case the device is too tightened and does not come off the shoes, slightly release them turning a little the crown on the adjustment bolt.

 There is a specific play between the drum and the linings, which corresponds to its value if the adjustment is correct and the drum does not present excessive wear, in this case, when the parking brake is applied on the actuation lever in the cab, the total braking should occur on the third ratchet notch.

This adjustment will be carried out at the joint of the front and rear cables in the next operations and will be reflected in the stroke of the lever.

*BE42.20-B-1011-01C

9

Thoroughly clean the contact surfaces of the universal joint and of the drum. Install the transmission shaft so the marking made on the universal joint flange at disassembly coincides with the marking on the drum. Install the flange bolts and tighten them lightly crosswise and equally for the normal seating of the flange

 Finally, the same alternately and crosswise way apply the final specified tightening.



*BA41.10-B-1003-01G



*BA41.10-B-1004-01G

Adjusting the parking brake steel ropes

10

Secure the steel rope to be adjusted, front or rear with lock pliers at the hex metal parts (7), immobilize the adjuster of the brake cable (8) and turn the respective adjusting nuts (9) with an open end wrench until preventing the brake drum from turning

 In this position, actuate several times the lever on the ratchet for the accommodation of the components. Next, apply three notches in the ratchet and check if the brake locks the drum.

11

In case the drum is not locked at the third ratchet notch, repeat the previous adjustment of the item 10 until attaining total braking

12

Free the vehicle from the chocks and connect the battery leads

Turn on the master switch

 As this is about electronic vehicles, always follow the recommendations for this type of vehicle.

13

Confirm if the parking brake application indicator switch is operating

 When the parking brake is being applied after actuating the lever on the ratchet, the warning light in the instrument cluster will have to light up, telling the driver the parking brake is applied.

14

Take the vehicle for a test-drive and check on the parking brake behavior and especially that of the transmission shaft

Número

Denominação

Vehicles 979.013/ 016

BE42.20-B-1008-01C

Adjustment measure “C” between the actuation lever and the fastening stopper

Rear cable with new linings, regulated shoes and new drum

mm

101,5

BE42.20-B-1009-01C

Standard diameter “D” of the linings with adjusted brake shoes

Standard measure in the shoes for the adjustment of the cables

mm

241,25...241,45

BE42.20-B-1011-01C

Clearance between the linings and the drum

At each shoe

mm

0,37

Número

Denominação

Chassis 979.01/02/04, 979.07, 979.27

BA41.10-B-1003-01G

Prop shaft fixation

Terminals with tapped hole (clamps and bolts)

M10

Nm

65...80

M12x1,25

Nm

115...135

1/2"

Nm

160...180

For flanges

M10

Nm

60...70

M12

Nm

115...125

M14

Nm

140...200

M16

Nm

280...310

BA41.10-B-1004-01G

Transmission shaft in the parking brake drum

Only for chassis 979.01

M14x1.5

Nm

150...160