PAGE 50 — DCA-70SSJU SERIES — OPERATION AND PARTS MANUAL (STD) — REV. #5 (06/03/03)
DCA-70SSJU SERIES — TRAILER BRAKES MAINTENANCE
Hydraulic Surge Brakes
Hydraulic surge brakes (Figure 76) should not require any
special attention with the exception of routine maintenance
such as shoe and lining replacement. Brake lines should be
periodically checked for cracks, kinks, or blockage.
Figure 76. Hydraulic Brake Components
Brakes
Trailer 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.
Figure 74 displays the major hydraulic surge brake
components that will require inspection and maintenance.
Please inspect these components as required using steps 1
through 8 as listed below:
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. Adjust, 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 7 on the remaining brakes.
Actuator
Hydraulic surge braking requires the installation of an actuator
at the tongue of the trailer. Remember the
surge
or
push
of
the trailer toward the tow vehicle automatically synchronizes
the trailer brakes with the tow vehicle brakes. As the trailer
pushes against the tow vehicle the actuator telescopes
together and applies force to the master cylinder, supplying
hydraulic pressure to the trailer brakes.
Periodically check and test the surge “
actuator
” to make
sure that it is functioning correctly. Never use an undersize
actuator.
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