11.7. Repair of a reducer


Having established a reducer on a workbench, a key "on 10" we turn off two bolts of fastening of lock plates of nuts of bearings of differential and we remove plates.

We put with a core tags on a bed and the corresponding cover of the bearing that at assembly to establish covers on the places.

Key "on 14" we turn off bolts of fastening of covers of bearings.

We take out external rings of bearings and adjusting nuts from the differential case.

If we do not change bearings, then we mark external rings not to mix them in places at installation since bearings were individually earned extra and it is undesirable to razukomplektovyvat them.

We check lack of radial side plays in gear wheels of half shafts.

By stripper it is pressed internal rings of conic bearings.

Key "on 17" we turn off eight bolts of fastening of the conducted gear wheel to the case of differential and we remove it.

To small beards we beat out an axis of satellites.

We turn gear wheels of half shafts and we take out gear wheels satellites.

We take out gear wheels of half shafts with adjusting washers, having marked their situation.

We take out the leading gear wheel and the deformed expansion plug from a case. At assembly of a reducer we replace it with new.

Drift from soft metal we force down an internal ring of the conic bearing from a shaft of the leading gear wheel.

Under the bearing the adjusting ring providing the correct relative positioning of gear wheels of the main transfer is established.

By the suitable tool it is beaten out external rings of conic bearings from a case.

Details of a reducer are washed carefully out in kerosene and attentively examined. At injury at least of one tooth (a vykrashivaniye, waves, risks, teases on working surfaces) we replace gear wheels new.
Sides between tops and working surfaces of teeths of the conducted gear wheel have to be sharp. If the slightest zaboina or curves are visible – we replace the main couple new.
We eliminate insignificant damages of an axis of satellites, necks of gear wheels of half shafts and their landing openings with a small skin with the subsequent polishing.
At assembly we replace a cuff, a nut of a flange and the expansion plug new.
If assembly of a reducer is made in a former case, then change of thickness of an adjusting ring of the leading gear wheel can be calculated as a difference in deviations of the amount of production of old and new gear wheels. The deviation in a size with a sign "" or "-" in the 100-th shares of millimeter is engraved on a shaft of the leading gear wheel.
For example, on an old gear wheel it is engraved –12, and on new 4. The difference of two amendments will make 4–(–12)=16. Means, the new adjusting ring has to be 0,16 mm thinner than old. At the return ratio of amendments (on old 4, and on new –12) the ring has to be 0,16 mm thicker than old.
For more exact determination of thickness of an adjusting ring we manufacture adaptation of an old leading gear wheel.

We weld a plate 80 mm long and tortsuy it in the size of 50-0,02 mm concerning the plane under the bearing. On a conic part of a shaft serial number and a deviation in a size is engraved.

Seats under bearings are ground (it is possible to process a small skin) before the sliding landing.
We press external rings of forward and back bearings in a case.
We install an internal ring of the back bearing on the manufactured adaptation and we insert the device in a case. We establish an internal ring of the forward bearing, a flange of the leading gear wheel and we tighten a nut the moment 0,8–1,0 кгс.м.

We expose a case in horizontal position on level.

In a bed of bearings we put a round equal core (the extender from a set of face heads) and we determine by the flat probe gap size between it and a plate of adaptation.

We determine thickness of an adjusting ring as a difference between the size of a gap and a deviation of the size of a new gear wheel (taking into account a sign).
For example, the size of a gap makes 2,8 mm, and a deviation of the size of a gear wheel –15. Means it is necessary to establish an adjusting ring 2,8-(-0,15 thick) =2,95 mm.

We establish an adjusting ring of the required thickness on a shaft and by means of a piece of a pipe of the suitable size napressovyvay an internal ring of the bearing.

We insert a shaft into a case. We install the new expansion plug, an internal ring of the forward bearing, a cuff and a flange of the leading gear wheel.

Gradually we tighten a nut a dynamometer key until 12 кгс.м.

We define the moment of a provorachivaniye of a shaft of the leading gear wheel.

For this purpose on a neck of a flange it is reeled densely up in several turns strong thread and we fix to it a dynamometer. The effort at which the flange will begin to be turned evenly has to make 7,6–9,5 kgfs (that corresponds to torque 16–20 кгс.см) (for new bearings). If effort insufficiently – we hold out a flange nut. At the same time the moment of an inhaling should not exceed 26 кгс.м.
If when tightening a nut the moment of a provorachivaniye exceeded 20 кгс.см (9,5 kgfs), we sort a reducer and we replace the expansion plug.

We install the differential case together with bearings in a case and we tighten bolts of covers of bearings.

If the axial side play in gear wheels of half shafts was found, then at assembly we establish new, thicker basic adjusting rings. Semi-axial gear wheels have to rise in the differential case densely, but be turned by hand.

We make a key for an inhaling of adjusting nuts of a steel sheet 2,5-3 mm thick.

Adjustment of a gap in the main couple and the preliminary tightness of bearings of differential is carried out at the same time, to several stages:
we wrap a nut from the conducted gear wheel before full elimination of a gap in gearing;

We measure by a caliper distance between covers;

we wrap the second nut against the stop and we hold out it on 1–2 teeth of a nut. The distance between covers has to increase approximately by 0,1 mm;
rotation of the first nut we expose the required gap in gearing of 0,08-0,13 mm. It is minimum notable fingers the side play in gearing which is followed by easy knock of tooth about tooth;
hand we control constancy of size of a gap in gearing and it is gradually tightened both nuts until the distance between covers does not increase by 0,2 mm. It will provide a necessary tightness of bearings.

Slowly we turn the conducted gear wheel on three turns and at the same time we probe a side play in gearing of each couple of teeths.

If it is uniform in all provisions of gear wheels, then it is established lock plates. Reduction (increase) of a side play in any sector speaks about deformation of the case of differential and need of its replacement or a tortsevaniye on the lathe.
Lock plates happen two types: with one or with two pads.
Depending on the provision of a cut of a nut we establish one of them.