TM 55-203
levers on car are of same ratio as dimensions on badge
(b) Broken or part missing. Wear metal
plate.
broken through and sliding on reinforced back.
(2) Inspect bottom rod and brake beam safety
n. Clean, Test and Adjust Air-Operated Auto-
supports. Repair or renew as necessary.
mattec Slac Adjusters
(a). Brake beams, brake hangers, hanger
(1) Remove the capscrews that secure the air
pins, and brackets must be checked in accordance with
line adapter to the adjuster cylinder and separate from
the condemning limits shown below and renewed or
the cylinder and remove gasket.
repaired as necessary: (a)
Brake beam hangers of
(2) Refer to figure 8-3(2) and remove the three
round or other section, irrespective of original diameter
casing nuts and lockwashers that secure the engine
or thickness, if vertical thickness of top or bottom portion
portion to the adjuster body. Turn the engine portion off
is worn or reduced to 3/4 inch or less when measured
the adjuster screw and transport it to the airbrake shop
vertically or through the corners measured on the
for reconditioning.
radius.
(3) Remove the crosshead and adjuster screw
from adjuster body. Clean the screw threads thoroughly
(b) Brake beam hanger pins or bolts, originally
with a wire brush. Do not lubricate. The adjuster screw
1 inch in diameter, if worn to 7/8 inch or less.
nut should turn freely on the screw. If the threads of the
(c) Brake beam hanger pins, bolts or brake
screw or nut are excessively worn, replace with
connection pins, originally in excess of 1 inch in
serviceable parts. Blow out the slack adjuster air line to
diameter, if worn to 1 inch or less at any point.
insure that the brake cylinder port is open.
(4) Assemble the adjuster screw, crosshead,
(d) Brake beams should be renewed when
and reconditioned engine portion in reverse of removal.
tension rods are cut or worn 5/16 inch or more below
Use new gaskets between engine portion and adjuster
original diameter or when brake heads are worn so that
body and the air line adapter and the adjuster cylinder.
the vertical thickness of the top portion of top eye is
(5) Adjust brake cylinder piston travel as
worn 7/8 inch or less; center or upper hanger openings
follows:
are worn so that the opening measured vertically at
(a) Apply the brakes with full service
hanger bearing is 1 1/2 inches or more; the distance
application. With brake thus applied, measure and
between upper and lower brakeshoe lugs exceeds 2 1/4
record piston travel. Check all levers and rods for
inches measured at face of head; one or more toes are
proper clearance. Inspect brake cylinder and slack
broken or worn off to such extent that no portion will
adjuster connections for leakage.
contact the back of brakeshoe when brakes are applied;
(b) Release brakes and see if slack adjuster
brake hanger bracket cast integral with truck side
has operated. If the adjuster has not operated and the
bolster, having pin hole worn oblong to a depth of 1/2 of
shoes clear the wheels by 3/8 inch, no adjustment is
its original diameter, or worn oblong not more than 40
necessary. If shoes exceed 3/8 inch, adjust brake
percent, shall be restored to original diameter by
rigging manually. If the slack adjuster operates and
bushing or by fusion welding process. If the hanger
piston travel is excessive, adjust brake rigging manually.
bracket is not cast integral with truck side or bolster, it
(c) On swivel trucks where the brakes on
shall be repaired or renewed when pin hole is worn to
more than one truck are operated by the same cylinder,
the extent specified above.
adjust standing piston travel to 7 1/2 inches. Where the
Note. The wear limits prescribed above are
cylinder operates the brakes on one truck only and on
primarily intended to apply to inspection made of cars in
units equipped with truckmounted brake cylinders,
shops or on the repair track, as such parts cannot be
adjust the piston travel for that type of brake cylinder.
measured or gaged with any degree of accuracy without
o. Inspect Airbrake Hoses.
Carefully inspect
disassembly. The determination of condemning limits of
airbrake hoses and renew if found defective because of
these parts in tralnyards must therefore be left to the
the following wear limits:
exercise of good judgment by the trainyard inspector,
(1) Burst hoses.
(2) Leakage discernible without soapsuds
(3) Inspect brakeshoes for broken or missing keys
test.
and worn or damaged shoes. Brakeshoes shall be
renewed with any of the following defects:
(a) AAR standard type with 1/2 inch or less
wear metal. Composition type with 3/8 inch or less
thickness, including lining and backing plate.
8-19
Previous Page
