Minsk Tractor Works Belarus 1221.2 Disassembly-Assembly Manual Download

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Disassembly-assembly manual for tractor BELARUS-1221.2/1221

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b) extract spring 11, thrust 9 and retarding valve 4;

) unscrew two bolt

for fastening cover 24, remove cover as an assembly with bushing 25 and

pusher 26 and extract control valve 3 from the side of removed cover, without removing retaining
ring from it;

d) check state of retaining ring put on control valve and control valve itself – deep scratches, mud

and foreighn particles in openings and on its surface, wash all dismounted parts with diesel fuel,
lubricate with motor or hydraulic oil;

e) insert retarding valve 4 inside control valve 3 with step side forward;
f) check how easily valve 4 moves inside control valve 3,absence of jamming – with valve fully

extended through side openings 3 mm in diameter of control valve openings 4 mm in diameter
should be visible on the valve, and when striking slightly control valve end face against hard surface
the valve should pop out of the control valve;

g) put control valve with stop ring, but without retarding valve, from top side (on the side of the

cover) inside the body, check easiness with which in axially moves – control valve inside body must
move under its own weight or at light shaking ov the body with control valve;

h) mount cover 24 as an assembly with bushing 25 and pusher 26, having checked state of rubber

rings and mud retainer inside bushing 25;

j) put retarding valve 4, thrust 9, spring 11 and having compressed spring with thrust, insert stop

pin 12 inside opening of control valve 3 and thrust 9, so that flats on the pin faced the body;

i) using screwdriver push support turn of spring 10, put it under flats of stop pin 12, and screw

spring on control valve until the second support turn goes under flats of of stop pin;

k) press the end face of control valve (with effort 15 kgf) and then release it, jamming of control

valve inside body is not allowed, total travel of control valve should be at least 8 mm.

Disassembly of relief and cut-off valves:

) unscrew plug 14 (Figure 9.2) on lower distributor end face (relief valve 2 can be seen through

side opening the second lowest end face groove of body of the distributor body);

b) extract spring 15;

) extract relief valve 2;

d) unscrew cut-off valve 16, holding from rotation of valve 2 by means of metal rod 4-7 mm in

diameter put in its side openings;

e) using wire 1-3 mm in diameter push stop pin out of cut-off valve body;
f) extract guide bushing 17, spring 18 and ball 19;
g) wash all parts in diesel fuel;
h) check state of sealing edge in body 1 (90 mm deep) – it should be free of cavities, cracks,

foreign particles, if necessary grind relief valve to this edge using fine-particle abrasive paste;

ij) check absence of foreign particles in jet openings with 1.8 mm in diameter along axle, and 1.3

mm in diameter along side surface of cut-off valve body 16;

j) check state of sealing edge of cut-off valve (for balls) – it should be free from foreign particles,

cavities, the ball track must be continuous along entire edge perimeter;

k) if necessary, mint the ball to seat with hammer strike having mass 0.15-0.25 kg;
l) put inside cut-off valve body 16 ball 19, spring 18 and guide bushing 17;
m) while pushing guide bushing align its side opening with side openings in cut-off valve body, put

stop pin;

n) screw cut-off valve 16 inside relief valve 2, putting on thread surface a drop of oil resistant paint

or sealant;