TM 9-2330-388-14
Section XIV. MAINTENANCE OF BOGIE ASSEMBLY
4-39.
General, M1098
(3) Check tightness of U-bolts and screws, fig.
4-41. They should be tight on leaf spring cap and seat,
(4) Look for cracked brake drum.
Table 4-5. Tabulated Torque Values - Bogie Assembly,
M1098
Location/Description
Spring U-Bolts (Nuts)
200-220 lb-ft
Spring Cap and Seat U-Bolts (Nuts)
200-220 lb-ft
Spring Cap and Seat Screws
240 lb-ft
Hub Cap Retainer Bolts
16-20 lb-ft
Figure 4-41. Bogie Assembly (M1098)
Wheel Stud Nuts
450-500 lb-ft
a.
Preliminary. Position semitrailer on hard level
(5) Look for damaged brake camshaft.
surface with front resting on landing gear. Jack and
block rear of frame. Remove wheels, para 4-51.
(6) Look for worn brake hoses or damaged
brake chamber.
b.
Inspection. Clean axle and suspension system
with water and fiber brush to allow for careful inspection.
(7) Check tightness of bolts which fasten bogie
assembly to trailer frame.
(1) Inspect general condition of trunnion tube,
axles, and spring leaves. Look for cracks or damage.
c.
Repair. Tighten loose bolts. If damage or wear
is evident, notify direct support maintenance.
(2) Check tightness of U-bolts, fig. 4-41.
Check clips on leaf springs, Table 4-5.
Section XV. MAINTENANCE OF BRAKE SYSTEM
forces the brake shoes against the brake drum causing
4-40.
General, M1098
friction to slow or stop the vehicle. When the brake is
released, spring action returns the brake shoes to
a.
Description. The semitrailer brakes are air-
release position.
operated cam-type brakes. Two brake camshafts, two
slack adjusters, and two brake chambers are assembled
c.
Brake Air System, Fig. 4-44. Compressed air is
to the front and rear axle.
The brake chamber
transmitted from the towing vehicle through the service
movement through the slack adjuster causes the
and emergency air lines. When the engine of the towing
camshaft to, rotate and force the brake shoes against
vehicle is running, air pressure of 90-120 psi is kept in
the brake drum, fig. 4-43.
the system though the emergency air line. Compressed
air is routed into the rear reservoir through the
(1) Attached to the slack adjusters are two
emergency relay valve. From the rear reservoir, the air
cam-shafts - one right-hand and one left-hand.
enters the front reservoir.
(2) The "S"-shaped part of the camshaft is
(1) The front reservoir is for the fail-safe
positioned between the rollers on the brake shoes.
brakes. A pressure protection valve between the two
reservoirs maintains approximately 75 psi of air in the
b.
Actuation. When ;the brake is actuated, air is
front reservoir for release of the fail-safe brakes.
applied to the brake chambers, and the diaphragm rod
moves the slack adjusters rotating the brake camshaft
against the two rollers on the brake shoes. This action
4-106
