Multiquip DCA-100SSJU— TRAILER BRAKING SYSTEM, Table of Contents, Electric Brakes

Table of Contents

DCA-100SSJU — TRAILER BRAKING SYSTEM

Brakes

If your trailer has a braking system, the brakes should be inspected the first 200 miles of operation. This will allow the brake shoes and drums to seat properly. After the first 200 mile interval, inspect the brakes every 3,000 miles. If driving over rough terrain, inspect the brakes more frequently.

Electric Brakes

Electrically actuated brakes (Figure 2) are similar to hydraulic brakes. The basic difference is that hydraulic brakes are actuated by an electromagnet.

Listed below are some of the advantages that electric brakes have over hydraulic brakes:

!An electric brake system can be manually adjusted to provide the corrected braking capability for varying road and load conditions.

!An electric brake system can be modulated to provide more or less braking force, thus easing the brake load on the towing vehicle.

!An electric brake system has very little lag time between the time the vehicle’s brakes are actuated and the trailer’s brakes are actuated.

!An electric brake system can provide an independent emergency brake system.

Road testing is necessary in order to properly synchronize the towing vehicle’s braking to the trailer’s braking. Brake lockup, grabbiness, or harshness is due to lack of

synchronization between the tow vehicle and the trailer being towed or under-adjusted brakes.

Before any brake synchronizations adjustments can be made, the trailer brakes should be burnished-in by applying the brakes 20-30 times with approximately a 20 m.p.h. decrease in speed, e.g. 40 m.p.h. to 20 m.p.h.. Allow ample time for brakes to cool between application. This allows the brake shoes to slightly be seated into the brake drum surface.

Figure 2 displays the major electric brake components that will require inspection and maintenance. Please inspect these components as required. Refer to Table 5 for electric brake troubleshooting guidelines.

Electric Brake Adjustment

1.Place the trailer on jack stands. Make sure the jack stands are placed on secure level ground.

2.Check the wheel and drum for free rotation.

3.Remove the adjusting hole cover from the adjusting slot at the bottom brake backing plate.

4.With a screwdriver or standard adjusting tool, rotate the star wheel of the adjuster assembly to expand the brake shoes.

5.Adjust the brake shoes outward until the pressure of the lining against the wheel drum makes the wheel difficult to turn.

6.Rotate the star wheel in the opposite direction until the wheel rotates freely with slight lining drag.

7.Replace the adjusting hole cover and lower the trailer to the ground.

8.Repeat steps 1 through 6 on the remaining brakes.

PAGE 14 — DCA-100SSJU — PARTS AND OPERATION MANUAL (STD) — REV. #2 (05/03/01)