Challenger Terra Gator 3244 Chassis. Manual - part 85

4-2

627333-A  

Brakes

Recommended Work Practices

1. Separate Work Areas. Whenever feasible, service

brakes in a separate area away from other

operations to reduce risks to unprotected persons.

2. Respiratory Protection. OSHA has set a maximum

allowable level of exposure for silica of 0.1 mg/m3

as an 8-hour time-weighted average. Some

manufacturers of non-asbestos brake linings

recommend that exposures to other ingredients

found in non-asbestos brake linings be kept below

1.0 f/cc as an 8-hour time-weighted average.

Scientists disagree, however, to what extent

adherence to these maximum allowable exposure

levels will eliminate the risk of disease that can

result from inhaling non-asbestos dust.

Therefore, wear respiratory protection at all times

during brake servicing, beginning with the removal

of the wheels. Wear a respirator equipped with a

high-efficiency (HEPA) filter approved by NIOSH or

MSHA, if the exposure levels may exceed OSHA or

manufacturers' recommended maximum levels.

Even when exposures are expected to be within the

maximum allowable levels, wearing such a

respirator at all times during brake servicing will help

minimize exposure.

3. Procedures for Servicing Brakes:

a. Enclose the brake assembly within a negative

pressure enclosure. The enclosure should be

equipped with a HEPA vacuum and worker arm

sleeves. With the enclosure in place, use the

HEPA vacuum to loosen and vacuum residue

from the brake parts.

b. As an alternative procedure, use a catch basin

with water and a biodegradable,

non-phosphate, water-based detergent to wash

the brake drum or rotor and other brake parts.

The solution should be applied with low

pressure to prevent dust from becoming

airborne. Allow the solution to flow between the

brake drum and the brake support or the brake

rotor and caliper. The wheel hub and brake

assembly components should be thoroughly

wetted to suppress dust before the brake shoes

or brake pads are removed. Wipe the brake

parts clean with a cloth.

c. If an enclosed vacuum system or brake

washing equipment is not available, carefully

clean the brake parts in the open air. Wet the

parts with a solution applied with a pump-spray

bottle that creates a fine mist. Use a solution

containing water, and, if available, a

biodegradable, non-phosphate, water-based

detergent. The wheel hub and brake assembly

components should be thoroughly wetted to

suppress dust before the brake shoes or brake

pads are removed. Wipe the brake parts clean

with a cloth.

d. Wear a respirator equipped with a HEPA filter

approved by NIOSH or MSHA when grinding or

machining brake linings. In addition, do such

work in an area with a local exhaust ventilation

system equipped with a HEPA filter.

e. NEVER use compressed air by itself, dry

brushing, or a vacuum not equipped with a

HEPA filter when cleaning brake parts or

assemblies. 

NEVER use carcinogenic solvents, flammable

solvents, or solvents that can damage brake

components as wetting agents.

4. Cleaning Work Areas. Clean work areas with a

vacuum equipped with a HEPA filter or by wet

wiping. NEVER use compressed air or dry

sweeping to clean work areas. When you empty

vacuum cleaners and handle used rags, wear a

respirator equipped with a HEPA filter approved by

NIOSH or MSHA, to minimize exposure. When you

replace a HEPA filter, wet the filter with a fine mist of

water and dispose of the used filter with care.

5. Worker Clean-Up. After servicing brakes, wash your

hands before you eat, drink or smoke. Shower after

work. Do not wear work clothes home. Use a

vacuum equipped with a HEPA filter to vacuum work

clothes after they are worn. Launder them

separately. Do not shake or use compressed air to

remove dust from work clothes.

6. Waste Disposal. Dispose of discarded linings, used

rags, cloths and HEPA filters with care, such as in

sealed plastic bags. Consult applicable EPA, state

and local regulations on waste disposal.

Regulatory Guidance

References to OSHA, NIOSH, MSHA, and EPA, which

are regulatory agencies in the United States, are made

to provide further guidance to employers and workers

employed within the United States. Employers and

workers employed outside of the United States should

consult the regulations that apply to them for further

guidance.

627333-A  

4-3

Brakes

Brake Operation

The two brake pads slide on the guide bolts in the

housing. When the brake is actuated, the cup springs

move the piston, adjusting screw thrust bolts and inner

brake pad contacts the brake disc. When the inner

brake pad contacts the brake disc, the housing shifts

onto the guide bolts and the outer brake pad pressed

against the brake disc also.

The brake is released by hydraulic pressure. When the

brake is released, the piston compresses the cup

springs, pulling the inner brake pad away from the

brake disc.

Brake lining and brake wear reduces braking force. The

brake must be adjusted to maintain braking force.

When replacing parts. Only use factory original parts

and part sets. Parts must be ordered through your

AGCO dealer. Any damage to parts not described in

this manual must be repaired or replaced using original

parts.

m

WARNING: Park the vehicle on the level

surface. Block the wheels to prevent the

vehicle from moving. Support the vehicle

with safety stands. Do not work under a

vehicle supported only by jacks. Jacks

can slip and fall over. Serious personal

injury and damage to components can

result.

FIG. 2:

m

WARNING: When the parking brake is

released, the vehicle does not have any

brake function. You must block the

wheels to prevent the vehicle from

moving. Serious personal injury or death

and damage to components can result.

FIG. 2

Q000059S

Brakes

4-4

627333-A  

CLEAN, DRY AND INSPECT

m

WARNING: Solvent cleaners can be

flammable, poisonous and cause burns.

Examples of solvent cleaners are carbon

tetrachloride, and emulsion-type and

petroleum-base cleaners. Read the

manufacturer’s instructions before using

a solvent cleaner, then carefully follow

the instructions. Also follow the

procedures below.

Wear safe eye protection;

Wear clothing that protects your skin;

work in a well-ventilated area;

Do not use gasoline, or solvents that

contain gasoline. Gasoline can explode.

You must use hot solution tanks or

alkaline solutions correctly. Read the

manufacturer’s instructions before using

hot solution tanks and alkaline solutions.

Then carefully follow the instructions.

Clean Parts

m

CAUTION: Do not use hot solution tanks

or water alkaline solutions to clean

ground or polished parts. Damage to

parts can result.

1. Use a cleaning solvent or kerosene or diesel fuel to

clean ground or polished metal parts or surfaces.

Examples of ground or polished parts are the

piston and the piston bore in the caliper;

2. Use a wire brush to clean fastener and fitting

threads;

3. Remove mud and dirt on the linings. Replace all

linings contaminated with oil or grease.

Dry and Inspect Parts

1. Use soft, clean paper or cloth rags or compressed

air to completely dry parts immediately after you

clean them;

2. Carefully inspect all parts for wear or damage

before you assemble them;

3. Repair or replace worn damaged parts.

Apply Corrosion Protection

1. Apply brake system hydraulic fluid to cleaned,

dried parts. Be careful that you do not apply the

grease to the linings or rotor.

2. If you will store the parts, apply a special material,

which prevents corrosion and rust, to all surfaces.

Store parts inside special paper or other material

that prevents rust and corrosion.

627333-A  

4-5

Brakes

SERVICE BRAKE

Release pressure

m

WARNING: Before disconnect brake

lines. Be sure there is no pressure in the

brake system. Even when the engine is

not running there can still be high

pressure in the brake system.

To release the pressure of the brake system, do the

follow steps:

•

Turn of the engine;

FIG. 3: Measure point (1) priority valve.

•

Connect a pressure gauge to the priority valve.

Place the pressure gauge  so it is readable for the

driver seat;

•

Keep pushing down the brake pedal until the

pressure of the brake system is completely gone.

Bleed Brake

NOTE: When you loosen any brake system hydraulic

connection, you must bleed the brake to

remove all air from the system.

1. Make sure that the master cylinder is filled to the

specified level with the type of hydraulic fluid

specified by the equipment manufacturer. Keep the

master cylinder filling during bleeding so that you

do not pull air into the system through the master

cylinder. Make sure the master cylinder is filled

when you are done bleeding the system.

2. Put a clear tube on the bleeder screw. Submerge

the other end of the tube in a clear container of the

specified fluid.

3. Bleed brake.

•

For full hydraulic system:

Slowly apply  low hydraulic pressure to the

brake. Loosen the bleeder screw. Continue to

apply pressure until no air bubbles appear in

the container of fluid. Tighten the bleeder

screw 12 - 16 Nm (9 - 12 lb-ft), then release the

pressure to the brake.

4. Check for fluid leaks.

FIG. 3

Q000094S

1