TM 5-3810-306-20
BRAKE CHAMBER INSTALLATION
TOOLS:
General mechanic’s tool kit: automotive (5180-00-177-7033)
SUPPLIES:
None
EQUIPMENT CONDITIONS: Disconnect ground cable at shunt. (Refer to page 8-109.)
Tire and wheel assembly removed. (Refer to page 12-2.)
REMOVAL:
WARNING
Never attempt to remove spring brake
chamber
clamp
(8)
without
first
caging spring brake (1). The spring
is powerful enough to cause parts to
fly apart with explosive force causing
personnel
injury
and
equipment
damage.
1.
MANUALLY CAGE SPRING BRAKE CHAMBER
(1).
a. Locate and remove caging bolt (2) nut (3) and
washer (4) on side of brake chamber.
b. Remove rubber cap (5) from rear of brake
chamber.
c. Install caging bolt into hole in brake chamber
and rotate one quarter turn to lock it in chamber.
d. Thread nut (3) with washer (4) on bolt (2) and
tighten 18-21 turns.
NOTE
Do not force nut beyond its normal
stop. Thirty (30) pounds-foot torque
is maximum that should be required.
Uncaging spring is accomplished by
reversing procedure.
2.
TAG AND DISCONNECT AIR LINES TO SPRING
BRAKE CHAMBER.
3.
REMOVE SPRING BRAKE CHAMBER.
a. Loosen collet nut (6) on stem of brake chamber
with a drift punch and hammer. Remove entire
brake chamber by threading it out of plunger
housing.
b. Pull wedge assembly (7) out of plunger housing.
INSTALLATION:
1.
INSTALL WEDGE ASSEMBLY.
a. Install wedge assembly (7) into the plunger
housing. Check for the correct roller-plunger
engagement by pushing on wedge rod by hand
while checking for plunger and shoe lift, or
measure standout of wedge rod from end of
threaded
housing
bore.
When
properly
assembled, wedge standout is 2.25 inches (57.2
mm).
2.
INSTALL BRAKE CHAMBER ASSEMBLY.
a. Install collet nut (6) on stem of brake chamber
housing (1).
b. Install air brake chamber by threading it into
plunger housing.
c. Tighten collet nut (6) on stem of air brake
chamber housing (1) using a drift and hammer.
11-4
