(1) Disconnect slack adjuster from brake air chamber push
rod by removing cotter pin and clevis pin.
and slide off slack adjuster.
of oil and slide slack adjuster into position.
rotary motion of slack adjuster as it reaches cam-
shaft splines will allow splines in adjuster to mesh
Install washer and snap
with splines on camshaft.
ring on camshaft.
adjuster to yoke of brake air chamber
with 1/2 x 1 13/64 clevis pin and 1/8 x 7/8 cotter
(3) Adjust brakes (par. 56c).
(4) Test air brake system (a above).
65. Air and Hydraulic Hose, Tubing, and Fittings, Test and
vehicle or other air supply, and brakes applied, coat air lines,
No leak is permis-
couplings, and connections with soapsuds.
b. L e a k a g e a t c o u p l i n g s i s u s u a l l y c a u s e d b y w o r n , d a m a g e d ,
Install new gaskets to stop
or improperly installed gaskets.
c. T i g h t e n a i r l i n e c o n n e c t o r s t o s t o p l e a k a g e .
d. T i g h t e n f i t t i n g s o n a i r l i n e s a n d a i r a n d h y d r a u l i c h o s e . I n -
s p e c t lines for partial restrictions caused by dents or kinks. Inspect
Replace with new piece of tub-
hose for wear, cuts, or breaks.
ing or hose or new fitting if damaged or if leak cannot be
Air-Over-Hydraulic Brake System (Semitrailer M270A1)
Hydraulic fluid should be checked when brakes
are adjusted or when new brake shoe linings are installed. If
the fluid is materially darker in color, as compared to new
fluid, watery in consistency, comparatively odorless, or lacks
a thin lubricating film when rubbed between the fingers, the
hydraulic brake system (fig. 10) should be drained, flushed, and
refilled with new fluid.