Disassembly
Before dismantling, unscrew the plug 4 (see fig. 184), drain the oil from crankcase 7, then fix it on bracket A.74076/R with support A.74076/1.
Unscrewing the nut 9 fastening the steering arm 8 and removing the spring washer 10, with a puller A.47043 (pic. 188) remove the bipod. After unscrewing the fastening bolts, remove the cover 5 (see fig. 184) together with adjusting screw 2, adjusting plate 1, lock washer and lock nut 3. Remove the bipod shaft 13 complete with roller 14, bearing 21 and axle 20 from the sleeve 12 of the crankcase.
Having unscrewed the mounting bolts, remove the cover 19 together with the shims 18. Using the shaft 15 of the worm 6, push the outer ring of the bearing 17 out of the crankcase and remove the shaft together with the bearing separator. Remove the oil seal 22 of the worm shaft and the oil seal 11 of the bipod shaft.
Mandrel 67.7853.9541 (pic. 189, a) press out the outer ring of the upper bearing 16 (see fig. 184). In this case, the nozzle on the handle of the mandrel is placed with the shoulder back (pic. 189.6).
Carried out on bracket A.74076/R in the reverse order of disassembly, taking into account the following:
- the outer ring of the upper bearing of the worm is pressed in with mandrel 67.7853.9541, rearranging the nozzle on the handle of the mandrel with the reverse side;
- after installing the worm in the crankcase of the steering mechanism and fixing the bottom cover, use the dynamometer 02.7812.9501 and head A.95697 to check the friction moment of the worm shaft, which should be within 2-5 kgf cm. If the friction torque is less than specified, reduce the thickness of the shims, and if more, increase;
- having installed the bipod shaft, make sure that there is no gap in the engagement of the roller with the worm in the positions of the worm shaft turned to the right and left by 30°from the neutral position of the bipod. Eliminate the possible gap with the adjusting screw 2 (see fig. 184) and tighten locknut 3;
- after adjusting the gap in the engagement of the roller and the worm, check with a dynamometer the moment of friction of the worm shaft, which should be equal to 7-9 kgf cm when the worm shaft is rotated 30°both to the left and to the right from the middle position and decrease smoothly to 5 kgf cm at turning from an angle of 30°to the stop.
Upon completion of the assembly, check the angles of rotation of the bipod from the neutral position, which should be 32°10'±1°both to the left and to the right until the bipod stops against the bolt heads, then pour 0.215 l of TAD-17i oil into the crankcase.
The dimensions of the main mating parts and the limits of permissible wear are given in Table. 10.