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

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8.6 BRAKE PEDAL FOR TRACTORS
W/HYDRAULIC BRAKES
The brake pedal is a pressure control valve.
It controls hydraulic pressure to brakes. The
normal position for the brake pedal is up.
To apply the brakes, push the pedal down.
To release the brake, let the pedal up.
8.7 BRAKE LIGHT SWITCH
ADJUSTMENT FOR TRACTORS
W/HYDRAULIC BRAKES
1. Thread adjusting screw until switch acti-
vates. Then, thread screw into the pedal
1/4 to ½ more turns.
2. Slowly apply pedal and note the point at
which the switch trips. Threading adjust-
ing screw in will raise the “trip” point,
backing screw out will lower the “trip”
point. Secure with jam nut once proper
setting is achieved.
3. Internal adjustments and tests are not in-
cluded with this manual. You may obtain
directions for them from the component
manufacturer or from NMC-Wollard, Inc.
8.8 BRAKE PEDAL FOR TRACTORS
W/AIR BRAKES
The brake pedal is a dual pressure control
valve. It controls air pressure to the air/hy-
draulic intensifiers. The normal position for
the brake pedal is up. To apply the brakes,
push the pedal down. To release the brake,
let the pedal up.
8.9 PARKING BRAKE AND CALIPER
See figure 8-3.
Shift to neutral and turn tractor off and
chock the wheels to prevent rolling while
servicing the parking brake.
8.9.1 Friction Pad Inspection And
Service
1. Replace the friction pads when the re-
quired adjustment of the castle nut (in-
structions follow) goes beyond the cotter
pin hole center line and there is not full
contact of the cotter pin in the castle nut
slots. Friction pads that wear down to
.060” minimum thick are no longer use-
able.
2. Unhook the parking brake cable clevis
from the cam lever noting which hole it is
assembled to. On air brake systems, un-
hook the air chamber linkage clevis from
the cam lever noting which hole it is as-
sembled to.
3. Remove the cotter pin and castle nut
from the cam stud. Remove the two push
pins. Clean and lubricate all surfaces of
the push pins, cam face where it con-
tacts the push pins and the threaded
cam stud. Use lube specification 20-003.
4. Pad/holder assemblies are secured to
the to the cam side casting and the car-
rier side subassembly with pad retainer
springs. Remove the springs to remove
pads. Slide new pad/holder assemblies
in place and secure by reinstalling the
pad retainer springs over the cam side
casting and carrier side sub assembly as
illustrated.
5. Install the caliper lever on the cam spline
so it points to the 9:00 position or toward
the driver and thread the castle nut onto
the threaded cam stud.
6. Rehook the parking brake cable clevis or
air chamber linkage clevis to the cam le-
ver which was removed in step 2. The
linkage should attach to the cam lever
without applying any force to the lever
with the brake released. If not, refer to in-
structions following for parking brake le-
ver or air chamber linkage.
8.9.2 Installing A New Caliper
1. The caliper is assembled to the caliper
support bracket so it is located on the
disc at the 9:00 position when viewed
PAGE 8-5
NOVEMBER 30, 2005
M200 MB4 Tow Tractor Manual No. 42975