BENDIX SD-05-4630 manual Brake Release, Yoke Designs, EASY‑ON Yoke Refer to Figure

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GENERAL SAFETY GUIDELINES WARNING! PLEASE READ AND FOLLOW THESE INSTRUCTIONS TO AVOID PERSONAL INJURY OR DEATH:

When working on or around a vehicle, the following general precautions should be observed at all times.

1.Park the vehicle on a level surface, apply the parking brakes, and always block the wheels. Always wear safety glasses.

2.Stop the engine and remove ignition key when working under or around the vehicle. When working in the engine compartment, the engine should be shut off and the ignition key should be removed. Where circumstances require that the engine be in operation, EXTREME CAUTION should be used to prevent personal injury resulting from contact with moving, rotating, leaking, heated or electrically charged components.

3.Do not attempt to install, remove, disassemble or assemble a component until you have read and thoroughly understand the recommended procedures. Use only the proper tools and observe all precautions pertaining to use of those tools.

4.If the work is being performed on the vehicle’s air brake system, or any auxiliary pressurized air systems, make certain to drain the air pressure from all reservoirs before beginning ANY work on the vehicle. If the vehicle is equipped with a Bendix® AD‑IS® air dryer system or a dryer

reservoir module, be sure to drain the purge reservoir.

5.Following the vehicle manufacturer’s recommended procedures, deactivate the electrical system in a manner that safely removes all electrical power from the vehicle.

6.Never exceed manufacturer’s recommended pressures.

7.Never connect or disconnect a hose or line containing pressure; it may whip. Never remove a component or plug unless you are certain all system pressure has been depleted.

8.Use only genuine Bendix® brand replacement parts, components and kits. Replacement hardware, tubing, hose, fittings, etc. must be of equivalent size, type and strength as original equipment and be designed specifically for such applications and systems.

9.Components with stripped threads or damaged parts should be replaced rather than repaired. Do not attempt repairs requiring machining or welding unless specifically stated and approved by the vehicle and component manufacturer.

10.Prior to returning the vehicle to service, make certain all components and systems are restored to their proper operating condition.

11.For vehicles with Automatic Traction Control (ATC), the ATC function must be disabled (ATC indicator lamp should be ON) prior to performing any vehicle maintenance where one or more wheels on a drive axle are lifted off the ground and moving.

and shaft. Worm and shaft rotation results in worm gear rotation, which in turn adjusts (or repositions) the brake camshaft.

When the foundation brake shoes contact the drum, the camshaft begins to resist rotation and friction between the worm gear and worm builds, preventing further rotation of the worm. Brake adjustment ceases at this point and further rotation of the Bendix® Versajustslack adjuster will cause the pinion and clutch spring to slip. The “free play” between the link teeth and pinion results in a predetermined lining-to-drum clearance.

BRAKE RELEASE

When the brake application is released, the brake actuator push rod returns the Versajust slack adjuster to the released position. During release, the Versajust slack adjuster rotates back toward the actuator causing the brake camshaft to again rotate, but in the opposite direction, and the brake shoes begin to move away from the drum. As the Versajust slack adjuster rotates back to the release position, the yoke again pivots causing the link to be pushed downward into the slack adjuster body. The “free play” between the link teeth and pinion is taken up during the initial part of the release. Continued movement

of the Versajust slack adjuster toward the released position causes the link to rotate the pinion. The anti‑reverse spring prevents counterclockwise rotation of the shaft and worm, causing the pinion and clutch spring to slip. The gripping action of the anti‑reverse spring – and slippage of the clutch spring during release – is due to the direction of the coil windings of each.

YOKE DESIGNS

The Bendix® Versajustslack adjuster may be equipped with either of two yoke designs. Both are designed to permit installation or removal of the slack adjuster, along with its yoke body and its attached adjusting linkage.

The brake actuator push rod must thread into the adapter a minimum of 1/2 inch and must not extend more than 7/64 inch beyond the other end of the adapter. The yoke adapters (quick connect & easy‑on) have either a 1 or 11/4 inch hex to allow tightening of the brake actuator push rod jam nut.

EASY‑ON YOKE (REFER TO FIGURE 2)

The easy‑on yoke assembly consists of an adapter which is threaded internally to match the push rod threads and externally to match female threads in the yoke. A special

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Contents General DescriptionOperation Brake ApplicationEASY‑ON Yoke Refer to Figure Brake ReleaseYoke Designs Initial Installation Preparation QUICK‑CONNECT YokeSlack Adjuster Arm Length Angle InstallationPreventive Maintenance Long Stroke Service InspectionActuator Stroke Table Standard Stroke Brake Maintenance Inspection Bendix Versajust Slack Adjuster RemovalCleaning and Inspection DisassemblyRetrofitting the Bendix Versajust Slack Adjuster ReassemblyAdjusted in an effort to Symptom Cause RemedySlack adjusters should Problem exists with