BENDIX A2LS Manuale - Pagina 10

Sfoglia online o scarica il pdf Manuale per Ricambi per auto BENDIX A2LS. BENDIX A2LS 17. Hydraulic drum brakes w/parking

Stampa la pagina

TAPPETS LOCATED OVER WEDGE,

CAGE & ROLLER ASSY.

STOP PIN

FIGURE 19 - EXPANDER TAPPET LOCATION

Note: Normal wear pressure marks should not be mistaken

for scoring. Some discoloration of the piston diameter

may be apparent; this is a normal result of brake

actuation over a long period of operation and should

be ignored.

4. Adjuster Shaft Assembly. Check for damaged threads.

Check the helix for burrs, corrosion, or missing teeth.

Check that the adjustment shaft turns easily in the piston

for the full length of the threads. Smooth with a fine

emery cloth or clean as required.

5. Manual Override. Check the teeth of the manual override

for wear or damage.

6. Housings. Examine the cylinder bores for signs of

corrosion, ridges, or score marks.

Note: Provided the cylinder bore surfaces are in perfect

condition, new seals, and if necessary, new pistons

may be used to rebuild the existing housings. If there

is any doubt as to the condition of the cylinders, new

wheel cylinder and expander units must be installed.

INPUT TAPPET/PISTON

SEAL POSITION

O-RING

ROLLER TAPPET/

PISTON

FIGURE 20 - EXPANDER WEDGE

ABUTMENT TAPPET

7. Backing Plate (dirtshield). Clean the backing plate with

a damp cloth and wire brush to remove any dirt or

corrosion from the surface of the backing plate.

IMPORTANT! PLEASE READ:

Do not use an air hose to blow dust out of the backing

plate (dirtshield). Never inhale dust from asbestos

brake lining. Asbestos dust, when inhaled, can be

dangerous to your health. Use a vacuum with a filter

to remove dust carefully from the backing plate and

drum.

8. Brake Drum. Inspect the drum for scores and cracks.

Refer to the vehicle service manual for inspection and

resurfacing procedures. Wipe drum clean with a cloth

dampened in Bendix Metal Clene. Do not contaminate

the braking surface of the drum with grease or brake

fluid.

REASSEMBLY

ASSEMBLE EXPANDER UNIT

Each Bendix drum brake repair kit contains a tube of

synthetic based grease that is recommended for all internal

expander parts (abutment tappet, roller tappet, piston, and

the wedge and roller assembly). This packaged grease, or

an approved substitute synthetic based grease, must be

used, and an adequate amount must be applied. Refer to

Figure 18 for identification of those parts being lubricated

with either the synthetic based grease or DOT 4 brake fluid

during assembly.

Use all of the parts supplied in the Bendix repair kit to replace

the old parts removed from the cylinders.

1. Clamp the expander housing in a bench vise with padded

jaws.

2. Thoroughly smear the wedge, cage, wedge seal and

roller assembly with the greased supplied. Fit the wedge

seal and retaining ring assembly as close to the cage

as possible.

3. Insert the wedge assembly into the expander housing

and retain with a new circlip.

4. Turn the expander housing in the vise to enable the

abutment tappet to be installed. Fit the dust boot to the

abutment tappet. Grease the inside of the dust boot and

the outside diameter and ramp face of the abutment

tappet with the grease supplied.

5. Insert the abutment tappet assembly into the housing

bore until it engages with the wedge cage and roller,

Figure 19. Install the dust boot to the end of the housing.

6. Smear the o-ring with the grease supplied and fit onto

the roller tappet/piston. Lubricate the piston seal with

new DOT 4 brake fluid and install the seal as shown in

Figure 20, with the lip of the seal facing outward toward

the pressure side. Liberally grease the ramp face and