NMC-WOLLARD MB-4 200-DF, Operation, Maintenance And Parts Manual

Page: 78 / 321

8.1 BRAKE SYSTEM DESCRIPTION
FOR TRACTOR W/HYDRAULIC
BRAKES
The service brake system consists of fully
enclosed, oil-cooled, wet disk brakes inside
front and rear axles.
The tractor hydraulic system is powered by
a gear driven pump on the transmission
and is used to activate the brakes and
steering. This system is separate from the
oil system used to cool brake disks and fill
the axle.
Periodically check fluid level in the hydraulic
reservoir.
The axle brakes effectively withstand repeti-
tive use without excessive fading and will
provide short stopping distances. These
brakes may remain effective over the life of
tractor and never require adjustment.
The park brake is a caliper type, completely
mechanical brake. The rotor is attached to
the output shaft on the transmission. The
brake is applied by pulling back on the han-
dle.
The Clark-Hurth (Dana) axle service man-
ual is included with this manual. It includes
detail information for maintenance, service,
and repair.
The brakes are powered by the tractor hy-
draulic system. See page 1-10 for hydrau-
lic system fluid specifications.
8.2 BRAKE SYSTEM DESCRIPTION
FOR TRACTOR W/AIR BRAKES
The service brake system consists of an air
over hydraulic system. An air compressor
mounted to the engine supplies the air. Air
is dried in the air dryer and stored in a three
tank system. The first tank is a reservoir.
From there the air divides into two tanks,
the primary and secondary. Both tanks are
equipped with check valves so if air pres-
sure is lost in one, the other will still main-
tain air pressure. When the brake pedal
(foot valve) is pressed down air pressure
from the primary tank flows to the rear
air/hydraulic brake actuator. Air pressure is
also sent to the front air/hydraulic brake ac-
tuator from the secondary tank. The air/hy-
draulic brake actuators are a combination of
a fluid actuator and an air chamber. The
pressurized air enters the air chamber and
pushes on a diaphragm, which creates hy-
draulic pressure in the hydraulic cylinder,
and hydraulic pressure is put to the brakes
in the axles. The front and rear are sepa-
rate brake systems. The brakes are en-
closed, oil-cooled, wet disk brakes inside
front and rear axles.
Periodically check the fluid level in the hy-
draulic reservoirs on top of the air/hydraulic
brake actuators.
The brakes effectively withstand repetitive
use without excessive fading and will pro-
vide short stopping distances. These
brakes may remain effective over the life of
tractor and never require adjustment.
The parking brake is to the right of the con-
trol panel. It is yellow and reads System
Park. When pulled the air is released from
the parking brake chamber and the springs
force the brake shoes together against the
parking brake disk. The parking brake is at-
tached to the transmission.
The Clark-Hurth (Dana) axle service man-
ual is included with this manual. It includes
detail information for maintenance, service,
and repair.
M200 MB4 Tow Tractor Manual No. 42975
PAGE 8-2
JULY 15, 2001