Bendix Commercial Vehicle Systems A2LS HYD DRUM BRAKES W/PARKING 2/08 User Manual
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FIGURE 22 - PISTON ADJUSTER
FIGURE 23 - NEW AND OLD STYLE PISTON AND OVERRIDE
WHEEL
insert the assembly into the bore of the housing until it
engages the wedge cage and rollers, Figure 16. Install
and tighten the stop pin to 16 ft. lbs. (23,3 N.m).
7. Fit the dust boot to the input tappet/piston, lubricate the
piston seal with new DOT 4 brake fluid and install the
seal onto the piston with the lip facing inward, Figure
20. Grease the inside of the dust boot with the grease
supplied and install the input tappet/piston assembly into
the housing bore until it rests on the roller tappet/piston.
Fit the dust boot to the end of the housing.
8. Turn the expander housing in the vise to enable the
wedge return spring to be installed. Locate the spring
ferrule on the spring and compress the spring over the
wedge stem until the pin can be inserted, Figure 16.
Release the spring carefully.
Note: Push in wedge assembly slightly and center it inside
the housing.
9. Install the bleed screw.
10. Install the expander to the backing plate (dirtshield) using
a new gasket, Figure 1, and secure in place with fixing
bolts.
11. Refer to the vehicle service manual and stall the parking
brake chamber. Install bridge pipe and hydraulic hose.
12. Install the brake shoes following procedures under Brake
Shoe Installation in this manual. Refer to the vehicle
service manual for procedures to bleed the air from the
brake system. After bleeding, manually readjust the brake
shoe to drum clearance as necessary. Refer to Brake
Shoe Adjustment in this manual.
ASSEMBLE WHEEL CYLINDER UNIT
Use all of the parts supplied in the Bendix repair kit to replace
the old parts removed from the cylinder.
1. Lubricate the piston seal, Figure 15, with new DOT 4
brake fluid and install the seal onto the piston with the
lip facing inwards, Figure 21.
Install the dust boot to the piston and smear the inside
of the dust boot with the grease furnished in the kit.
OVERRIDE
WHEEL
RETAINER RING
RETAINER
RING
GROOVE
IN PISTON
OLD STYLE
GROOVE IN PISTON
HAS BEEN ELIMINATED
OVERRIDE WHEEL
NEW STYLE
FIGURE 21 - WHEEL CYLINDER
PISTON
SEAL
DUST BOOT
SCREW ON FULLY AND UNSCREW ONE
COMPLETE TURN