SAF-HOLLAND XL-AM20006BM Brake and Service Chamber - Manual (Page 13)

13 XL-AM20006BM-en-US · 2014-04-22 · Amendments and Errors Reserved · © SAF-HOLLAND, Inc., SAF-HOLLAND, HOLLAND, SAF,
and logos are trademarks of SAF-HOLLAND S.A., SAF-HOLLAND GmbH, and SAF-HOLLAND, Inc.
4. Apply the brakes (brake linings making contact with
the drum) and verify that the spring brake meets the
following conditions:
„ 90° angle between the centerline of the slack adjuster
and the push rod (Figure 18).
„ 90° angle between the push rod and the mounting
surface of the spring brake (Figure 18).
NOTE: Failure to meet these conditions will require
the replacement of spring push rod. For more
information regarding push rod lengths consulting
the vehicle manufacturer.
5. Release the brakes and measure the length of the push
rod from the surface of the service base to the centerline
of the clevis pin, dimension “A“. Record this dimension
(Figure 19).
6. Apply pressure to emergency side and uncage the brake by
turning the release bolt nut counter clockwise with finger
or a hand wrench, DO NOT use an impact wrench. Turn the
release bolt counter clockwise 1/4 turn and pull out.
7. Measure the clevis throat on the brake to be installed,
dimension “C“ (Figure 20).
8. To determine the correct push rod length, subtract
dimension “C“ from dimension “A“. This will provide the
correct push rod length.
EXAMPLE:
Dimension “A“ = 5" (127 mm) push rod with clevis length
(old brake installed)
Dimension “C“ = 1.25" (31.8 mm) clevis length of the
spring brake to be installed
“A“–“C“ = 5"–1.25" (127 mm – 31.8 mm) = 3.75" (95.2 mm)
9. Mark the correct length on the push rod. Use the jam nut
to facilitate marking the correct length. Cut the push rod
using the best cutting device available.
10. Attach the clevis to the push rod. Make sure that no more
than 2 threads (approximately .12" (3 mm)) extend into
the clevis throat to ensure no interference or no less than
1 thread is recessed into the clevis. Torque jam nut on
DMFWJTUPGUMCT /tN Figure 20
CLEVIS THROAT DEPTH
C
Figure 18
CORRECT WHEN SERVICE
BRAKE IS APPLIED
(EMERGENCY BRAKE CAGED)
CL
CL OF
PUSH ROD
BRAKE APPLIED
90° 90°
Figure 19
CORRECT WHEN SERVICE
BRAKE IS NOT APPLIED
(EMERGENCY BRAKE CAGED)
CL
CL OF
PUSH ROD
BRAKE NOT
APPLIED A
B
Determining Correct Push Rod Length