Adjustment of the gearbox "GAZelle" with their own hands

The well-known phrase about the ignorance of everything under the Moon immediately surfaced in the head of the owner of "GAZelle", as soon as his ear catches an extraneous rumble somewhere below when the car moves. Most often this is observed when driving at a speed of at least 30 km / h.

An experienced driver will immediately determine the cause of the occurrence of a "freelance" sound: the rear axle, the adjustment of the GAZel reducer is required. But the devil is not so terrible as he is painted. Extraneous hum can be completely eliminated, and with our own hands.

This is serious

To engage in "freelance" sound should be immediately, because delay is like death (reducer). Violation of the mode of interaction between the gears will lead to their rapid wear and breakdown of the reducer. Do not postpone the problem in a long box, you need to immediately begin to eliminate it.

Of course, it's not a simple matter - adjustment of the rear axle reducer ("GAZelle" - with their own hands a completely repaired car, as you know). Therefore, one must be prepared that the first results may be far from expected.

But do not despair in the event of an unsuccessful adjustment, but you need to read the "Operation and Repair Manual" once again and repeat all over again.

Where to begin

Adjustment of the gearbox "GAZel" first of all will require from you a trivial operation - draining the transmission oil.

First of all, it is necessary to heat the oil in the gearbox. To do this, you can drive by car or by raising the rear axle on the jacks or the lift, start the car and turn on the gear. This is necessary for a high-quality drain of oil from the gearbox.

After draining the oil in a suitable container, you should immediately inspect it for any metal chips. The presence of metal in the oil indicates the wear of the gears gear and the need for their replacement with the subsequent adjustment of the reducer.

Having convinced of necessity of repair of a reducer, we remove it and dismantle. If parts of the mechanism have shells, chips and other defects, then such parts must be replaced and the reducer must be adjusted.

Adjustment of the bearing temperature gap

Adjustment of the gearbox "GAZelle" is done after the final assembly of the mechanism. By assembling the gearbox, you can proceed with its adjustment.

For the convenience of the adjustment work, we install the assembled gearbox on the stand and fix the bearing rods with a force of up to 9 kgf. Then, by adjusting the thermal gap in the bearings with a special key (a plate, possibly with a welded centering sleeve and handle), tighten the front yoke nut to the stop, and then release it by 3 mm (the distance is well determined by a special movement indicator).

Adjustment can be carried out without the use of a movement indicator. In this case, the yoke nut is tightened to the stop, and then released into one slot in it. The nut must be free to rotate by hand.

This is quite enough to create a temperature gap of the bearings.

Adjustment of the gear of the planetary gear with the shank

It is necessary to establish a clearance between the planetary gear and the shank. For this we make a mark on the yoke against the cutout of the yoke nut. We set the displacement indicator on the "planetary" and, turning the shank of the reducer, determine the required clearance. Its value should be 0.15-0.18 mm.

If the gap is large, then do the following:

• Unscrew the front leg clamping nut to one notch from the mark placed before it;
• We tighten the rear side bearing yoke one cutout;
• Check the clearance obtained after adjustment;

If the loosening of the nut on one cutout does not lead to the desired gap, we adjust the nuts for one more cutout. This is done until the required clearance between the shank and the planetary is reached. After that, we fix the locks on the yoke nuts.

Such actions do not disturb the adjustment of the differential temperature gap, which, in turn, will not cause the reducer to overheat in the future.

Check the quality of the adjustment on the stand

The tooth contact patch is the correct way to correctly determine the quality of the rear axle reducer adjustment ("GAZelle" is not an exception) in any car.

For this, the driven gear (its teeth) is painted with bright paint.

Then it is necessary to turn (repeatedly and in both directions) for a flange leading gear, braking the driven one. This operation is done before removing the paint in the areas of contact of the teeth (the appearance of the contact spot).

The location of the spot will tell the flaws in the adjustment done earlier.

If it is in the tooth tip area, then you should put the ring of the drive gear of greater thickness. But if the stain is located at the base of the tooth, then the thickness of this ring should be reduced.

In the case where the stain was on the narrow end of the tooth, the distance between the leading and driven gears should be increased. If the spot is observed at the wide end, then this gap should be reduced.

If the spot is in the right place, it means that the adjustment of the rear gearbox has been successfully completed, "GAZelle" is now ready for practical testing of the quality of the adjustments performed. We leave for a small trip to make sure there is no "freelance" noise.

Check the quality of the adjustment in motion

After the adjustment of the GAZel reducer is performed, it is necessary to check its quality practically on the go. Do not forget to pour oil in the reducer of the bridge, prescribed by the "Operation and Repair Manual".

The check is carried out in motion, the speed should be of the order of 60-70 km / h, the duration of the trip is 20-30 minutes. The indicator of the adjustment quality will be the crankcase heating temperature - not more than 95 degrees Celsius.

Protect the reducer

To ensure that the rear axle gearbox is guaranteed to have fulfilled its life, it is necessary to use it carefully and competently.

First of all, do not:

• Overload the car, especially in hot weather;
• To represent himself as Schumacher and make sharp starts;
• To overcome "in one fell swoop" long rises - this will lead to overheating of the reducer;
• Pour oil into the crankcase of the reducer, and also violate the frequency of its replacement: in the summer - every 35 thousand km, in winter - after 40 thousand km.
• Forget to check the clearance of the shank with each oil change. If it is found, it should be fixed immediately;

By the way, the adjustment of the steering gearbox ("GAZelle" is meant) is carried out using a similar technology.