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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o) insert relief valve 2 inside body 1 of distributor, check how easily it rotates inside body –
movement must take place under its own weight or upon light touch of little finger of hand;
р ) put spring 15 and screw plug 14, having checked state of rubber sealing ring on it;
q) check operation of relief valve 2, by pulling valve by visible in side body opening using prickle or
narrow screwdriver, and then sharply releasing it. The valve must return to initial position with click
(strike against sealing edge).
Disassembly of reverse valve:
а ) unscrew plug 8 (Figure 9.2) (ball 6 of reverse valve is seen through side opening in the first
lowest distributor end face groove);
b) extract spring 7 and ball 6;
с ) wash parts in diesel fuel;
d) check state of valve seat; its sealing should be free of cracks, foreign particles,ball track must
be continuous along entire edge perimeter;
e) if necessary, mint the ball to seat with hammer strike having mass 0.15-0.25 kg;
f) put spring 7 and screw plug 8, having checked state of rubber sealing ring on it;
g) using prickle or narrow screwdriver check mobility of reverse valve ball: it should part from seat
by at least 2 mm and return back without jams upon tool removal.
Disassembly and inspection of balance valve:
а ) unscrew conical plug 23 (Figure 9.2) on top end face of distributor;
b) extract spring 22 and ball 21;
с ) check state of sealing edge inside body above ball. If necessary, mint the ball to seat with
hammer strike having mass 0.15-0.25 kg is allowed. If deep cavities are present edges can be
corrected by deepening the opening by 0.5-2 mm using drill 7.8-8.4 mm in diameter at summit not
less than 120 degrees and minting. The resulding chips must be removed completely.
Disassembly and assembly of plunger cylinders:
а ) put cylinder in bench vice, carefully squeezing its body 1 (Figure 9.3) so that through the
opening cylinder cavity could be seen;
b) move plunger 3 of cylinder in such position (with plunger almost entirely extended), that stkop
ring 2 on it and adjacent groove were opposite feeding opening;