Minsk Tractor Works Belarus 1221.2, Disassembly-Assembly Manual

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Disassembly-assembly manual for tractor BELARUS-1221.2/1221 В .2/1221.3/1221.4
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2 – adjustment bolt; 3 – checknut
Figure 4.141
b) screw bolts 2 inside adjustment yokes or unscrew them to an extent that full travel of brakes’
right-side pedal was in the range of 115…125 mm upon effort 120…130 N, and braking distance
was no more than 6 m at speed of 20 km/hour with effort no more than 600 N on pedals interlocked
with bar, and also non-simultaneity of wheels braking start no more than 1 m (by impression). Travel
of left-side brake pedal must be 5…20 mm shorter than travel of the right-side brake pedal in order
to provide simultaneous actuation of brakes in the interlocked position. Reduction of brakes’ pedals’
travel to less than above-mentioned values is not permitted, as this leads to premature wear of facia
and overheating of brakes.
с ) tighten check nuts 3.
Ingress of grease inside dry friction brake causes oiling of disks, reduction of friction force
between their working surfaces, brakes “don’t hold”. In this case disassembly the brake, eliminate
oil leakage, wash oily disks with benzene and let them dry up for 5…8 min. After assembly adjust
brakes control.
4.6.15 Adjustment of parking brake, brake valve and regulator of pneumatic system
pressure
Put tractor on even terrain, shut down the diesel, lock rear axle from front and back, and perform
the following operations:
а ) shift lever of parking brake control 1 (Figure 4.142) to front position (push);
b) loosen checknut of adjustment bolt 8 (Figure 4.143), and check nut 7 and pull out pin 5;
с ) shift lever 4 and align top edge of groove “ В
1
” of lever 2 with top edge of groove “ В
2
” of lever 3
of the brake right-side pedal, and then, rotating yoke 6, align openings of lever 4 and yokes 6 and
insert pin 5;
d) unscrew or screw bolt (8) so that when pulling control lever with effort 200+
10
N the latch was
retained inside hollow of the third and fourth teeth of sector “ А ”. After adjustment tightened loosened
checknuts.
Make final check and adjustment of the parking brake on the assembled tractor. Tractor must be
retained on grade not less than 18% when to parking brake lever (1) effort no more than 400 N is
applied. Where necessary, correct adjustment using adjustment bolt 8.