Gearboxes differ in speedometer drives, each of which corresponds to its final gear ratio. For external distinction, a mark is applied to the speedometer drive with paint: blue for the final gear ratio of 3.9; red for 4.1, not stained for 4.3. In addition, on the clutch housing (opposite the breather) the marking is applied with paint, the number 5.
On the described models, a four-speed gearbox with synchronizers in all forward gears is installed. Some cars are equipped with a five-speed gearbox, made on the basis of a four-speed gearbox.
The gearbox consists of a crankcase 46 (pic. 115), in which the primary, intermediate and secondary shafts with gears and synchronizers are located, and a mechanical gear shift drive.
Pic. 115. Gearbox:
1 - input shaft seal; 2 - rear bearing of the input shaft; 3 - clutch housing; 4 - bearing adjusting ring; 5 - needle bearing of the secondary shaft; 6 - thrust washer of the IV gear synchronizer spring; 7 - ring gear synchronizer IV gear; 8 - breather; 9 - synchronizer clutch of III and GU gears; 10 - synchronizer clutch hub; 11 - retaining ring of the synchronizer blocking ring; 12 - synchronizer blocking ring; 13 - synchronizer spring; 14 - driven gear III gear; 15 - driven gear of the 2nd gear; 16 - secondary shaft; 17 - driven gear of the 1st gear; 18 - bushing gear 1st gear; 19 - intermediate bearing of the secondary shaft; 20 - locking plate; 21 - reverse driven gear; 22 - lever rod; 23 - thrust pad; 24 - elastic pillow; 25 - remote bushing; 26 - locking sleeve; 27 - speedometer drive gear; 28 - output shaft seal; 29 - flange of the elastic coupling: 30 - nut; 31 - centering ring seal; 32 - retaining ring; 33 - centering ring; 34 - rear bearing of the secondary shaft; 35 - mud deflector; 36 - driven gear of the speedometer drive; 37 - rear cover of the gearbox; 38 - speedometer drive; 39 - reverse fork; 40 - reverse drive gear; 41 - intermediate reverse gear; 42 - the axis of the intermediate gear; 43 - rear bearing of the intermediate shaft; 44 - drive gear of the 1st gear; 45 - synchronizer clutch of I and II gears; 46 - gearbox housing; 47 - drive gear of the 2nd gear; 48 - 3rd gear drive gear; 49 - plug of the filler and control holes; 50 - lower cover of the gearbox; 51 - intermediate shaft; 52 - gear wheel of constant engagement of the intermediate shaft; 53 - front bearing of the intermediate shaft; 54 - bearing clamp washer; 55 - bolt; 56 - gear wheel of constant engagement of the input shaft; 57 - spring washer; 58 - retaining ring; 59 - front cover of the gearbox; 60 - input shaft.
The input shaft 60 rotates in two bearings: the front one is located at the end of the crankshaft, the rear one is located in the gearbox housing housing. The shaft has two toothed rims. The gear of constant engagement of the input shaft 56 with oblique teeth is in constant engagement with the gear 52 of the intermediate shaft, and the ring 7 with straight teeth is the crown of the IV gear synchronizer. The intermediate shaft 51 is a block of four gears mounted in two bearings 43 and 53. The output shaft 16 is mounted on three bearings. It has two synchronizers. Each of them consists of a sliding clutch 9 and 45, a hub 10, blocking rings 12 and springs 13. The hub, rigidly connected to the secondary shaft, has external crowns, on which the sliding clutch 9 is located. shaft and gear 14 III gear. The rings are pressed against the conical surfaces of the clutch by springs 13. The reverse intermediate gear 41 is freely located on the axis 42.
The gears are switched using a mechanical drive, consisting of three rods, on which forks are fixed, which are included in the groove of the sliding clutches 9 and 45 of the synchronizers, and the fork 39, which is included in the channel of the reverse gear 41.