Each axle is equipped with independent com-
as it is being rotated back from the DUMP position.
ponents so that an appilcation of the service brake
pedal actuates both systems simultaneously. If air
The bucket may be stopped and held at any po-
p r e s s u r e is lost in either the front, rear or both
sition of its dumping arc by placing lever in the
systems, the safety brake for that system is auto-
HOLD (neutral) position.
matically applied to bring the machine to a safe
controlled stop.
Parking Brake Lever applies mechanical brake
on drive line. To set brake, pull up and back on
l e v e r . To release brake push lever forward and
Additional braking protection is provided by an
emergency system, manually controlled by a hand
down.
v a l v e located in the operator's compartment. A
Pedal design permits brake application
Brake
dash mounted light and buzzer warn the operator
with either
left or right foot of operator. Pedal ac-
when air pressure reaches the minimum safe limit,
tuates an
air valve for applying brakes at all
see Figure 10. If the operator does not stop, the
wheels. As
pedal pressure increases, air valve opens
brakes are automatically applied when air pressure
wider, and
brake application becomes more severe.
drops below safe operating limit.
T h e left hand brake pedal also operates a de-
CAUTION: When safety brakes are actuated, the
clutch or shut-off valve in the transmission control
machine must not be moved until air pressure is
cover which blocks off hydraulic pressure to the
returned to safe operating level.
forward clutch in all speed ranges, thus disengag-
ing the forward clutch and establishing a transmis-
The emergency brake button is located to the
s i o n neutral when the left hand brake pedal is
immediate left of the right hand instrument panel.
applied. The reverse clutch is not affected.
It is a push-pull type control used to actuate the
manually controlled emergency system. Pull button
T h e right hand brake pedal by-passes the de-
out to apply brakes, push in to release brakes.
clutch valve, making it possible to apply the service
b r a k e s without de-clutching if so desired. This
permits inching the machine forward using service
WARNING: The emergency brake is not to be used
brakes and throttle.
as a parking brake since air pressure in the emer-
gency system bleeds down about 15 minutes after
The purpose of the de-clutching feature is to
the engine has been shut down.
prevent the machine from creeping forward when
loading or dumping the bucket, yet permits back-
ing away if operating on a sloping grade. It also
increases boom and bucket hydraulic system work-
ing power by blocking the power transmitted to the
wheels.
C i r c u i t Breaker Reset Button is located on
right rear frame rail next to starter motor assem-
b l y . Press button and hold momentarily to reset
c i r c u i t breaker whenever circuit breaker has been
tripped.
S a f e t y Brakes: A safety feature has been in-
corporated in the air over hydraulic disc brake sys-
tem on Model 175B Tractor Shovels. It consists of
automatically applied, low pressure actuated, front
B. Warning Light
A. Brake Hand Valve
and rear axle braking systems, with a manual con-
trol feature.
Fig. 10. Brake Manual Control & Warning Light
[ 10-01-5 ]