DIY uaz box repair

Dismantling the gearshift mechanism
SEQUENCING

Use a narrow slotted screwdriver to knock out the plugs of the gear shift rods.

Using the "17" key, unscrew the plug-plug of the retainer socket.

Using pliers, remove the safety wire of the bolts securing the forks to the rods ...

... and turn off the three bolts with a 10 key.

We knock out the fork rod of the 1st-2nd gear with a beard together with the plug.

We take out the plug and stem.
In order not to confuse the rods, we immediately put the forks on them and fix them with bolts.
Similarly, we knock out the fork rod of III-IV gears), ...

The blocker pin is located in the middle rod.
Knocking out the rod of the reverse gear fork, ...

... take out the ball with a spring.

Using the "10" key, unscrew the three bolts securing the fuse cover.

We take out the ball with a spring (fuse holder).

Sinking the ball with a slotted screwdriver, insert the stem into the hole in the cover.

We put a fork on the stem, tapping on the end of the stem with a soft metal hammer, ...

... and fix it with a locking bolt, aligning the holes of the stem and the fork.

Install the plunger into the channel between the reverse gear fork and the III – IV gears.
Similarly, install the III – IV gears rod with a fork and the second plunger (between the III – IV and I – II gears).
We install the rod of I – II gears, a fork, a ball with a spring and a stopper plug.
Clamping the switching mechanism in a vice and installing a lever on it, we check the correct assembly and operation of the mechanism. The rods should be easy to move and clearly fixed.
Counter bolts of gear shift forks with safety wire.

Orient the oil deflector washer with a protrusion to the inner ring of the bearing.

The bearings are pressed onto the shaft with a piece of pipe of a suitable length and corresponding diameter.
We carry out further assembly of the gearbox in the reverse order, while degreasing the gaskets and bolts of the crankcase covers and applying sealant to them.
We check the gear shift on the assembled box by turning its shafts by hand. Having installed the gearbox on the car and filled with oil, we check its operation in motion. Transmissions should turn on clearly, without jamming and noise. At the same time, make sure that the gears are fully engaged.

ATTENTION
The lever travel when engaging the first gear in a gearbox with synchronizers only in III-IV gears is 2.5 times greater than when engaging the second gear. Failure to engage the first gear causes rapid wear and destruction of the gears.

The original article is on the site

Thanks to Alexander Dorokhov for sending me a lot of pictures of his box. Using these pictures as an example, I wrote this article.

This photo shows the cover with the shift forks. Visually, I didn't notice any wear on the forks! But be sure to move your hands forks. If they start to dangle on the rods - So it is necessary to unscrew the wire that fixes them and tighten the bolts stronger! So that visually they look great.

Now looking inside the box. One can only breathe. Here you don't even need a dipstick to see how much the second gear gear is worn out by the end of the secondary shaft in the area of ​​the coupling teeth. Ideally should be 0.2mm. On the one who worked, of course, a little more. But here you can clearly see that the gap is at least 3.5mm. Such a gear is only ejected. Because her coupling teeth will only grasp halfway. Compare the length of the teeth and the width of the backlash yourself.

When the input shaft is removed, inspect it. The synchronizer is no longer good for anything, since its guide teeth are clogged to dullness.The clutch teeth have already done a good job. From the bottom of the teeth, uniform strips of working are clearly visible. But from above, on the other hand, rust is clearly visible on the far half of the tooth. This suggests that the gear clutch, when the gas was released, became sideways or was squeezed out. So that the input shaft is ejected together with the synchronizer.

We take out the synchronizer sleeve with the hub. Visually. The 4th gear teeth at the clutch look great. Unfortunately, their lateral wear from the teeth of the input shaft is not visible?

I wonder if the retaining ring came out by itself? If so, then the retaining groove on the output shaft broke into a cone and the ring squeezed out of it under load. So you have to go to the turner and he will neatly straighten this red-hot groove with a very strong cutter. Behind the ring you can see a spacer sleeve or washer, whichever you want. It will be necessary to put a new bearing on the shaft at the turner, put the retaining ring back in the groove, and the turner will immediately grind you a new spacer washer. The washer must be so thick that it fits between the bearing and the retaining ring with a slight interference or no more than 0.1 mm in the red. Although it is possible the store sells new circlips and spacer sleeves of different thicknesses. In any case, for a land Rover, this is how it is done. But I hope the retaining ring has been removed.

Here, too, I see a kind of wear on the walls. If yes! That means you need to put a new lock washer of greater thickness. But, if the synchronizer hub also dangles on the shaft splines. It's best to change the shaft too! Although the splines look neat and there are no signs of wear. Most likely the shaft is in good condition.

Addition to the written:
The circlip itself can play along the shaft in the groove. The main thing is that when the gear of the third gear and the synchronizer clutch are mounted on the shaft, the gap between the retaining ring and the synchronizer clutch is minimal. That is, the larger the gap, the more the gear and the clutch dangle on the axle. Therefore, we are trying to ensure that all gears and couplings have the minimum possible backlash. Ideally between 0.1 and 0.2mm. Although I collected boxes in which this backlash was 0.5 mm. But the less the better. If the gap between the lock washer and the synchroniser hub is greater than a millimeter? You need to use a thicker lock washer. Or it is more difficult to act if the backlashes are not removed, because the gear of the third gear is new, and the end of the shaft to which it is pressed is already badly worn. It is necessary to grind this end a little on the shaft against which the gear is pressed. And put there a bronze washer 3.4mm thick. of such a thickness that she would select all the gears of the 3rd gear on the shaft and pulled the synchronizer sleeve up to the retaining ring.

The clutch and teeth facing the 3rd or 4th gear looks good. The edges of the teeth are intact. I do not observe oblique wear. But if the gears change, then the clutch automatically changes together with the hub. Although I would put this part together with the hub, just in case, in stock. And if the money is really not enough, then I would put it. If everything is correctly adjusted, nothing will dangle and the transmission has not been knocked out before. I don't see any crime. The main thing is that the hub fits snugly on the shaft.

The same goes for the hub.

The replacement synchronizer has blunt edges of the teeth. In this case, they will not slide to the side when the clutch teeth go through them, respectively, the gear lever will engage the gear with some difficulty.

The gear of the third gear has teeth clogged to a bluntness, and traces of chips are also visible. It will be difficult to turn on the third gear and even then every other time. She's not a tenant! Replacement only. The former owner obviously did not bother himself to wait until the synchronizers equalize the rotation speeds of the shafts. Moreover, Nigrol contributes to this.

And this is how she looks from behind.The spacer washer which stands behind is strongly worn out. It is necessary to buy a new washer, preferably fitting it in size. As a last resort, carve a new one out of bronze. On my Lada there is a bronze one. The main thing is that the gearwheel of the 3rd gear wobbled on the shaft no more than 0.2mm. And the copper bushing began to crumble. This means that the gear was simply dangling on the shaft. But she has a tolerance of 0.06 mm.

Now comes the tricky part. Yes, you can measure the inner diameter of the gear with an internal gauge or a dijetal caliper. Then measure the shaft neck, subtract one from the other and get the result. Unfortunately, this measuring tool is more expensive than a new shaft, and much more! Therefore, I can offer only two options.

1) The bushing on the new gear is still sized and you can hardly change anything here.

2) Now the way to check the runout of the shafts in the bushings. On fingers. And in the literal sense of the word. The human hand begins to feel the beating of parts in the region of 0.1 mm. Well, if you already feel the beating with a clear thud. This means that the beating is already in the region of 0.2mm. and more.

But the most important thing here is not the beating of the gear on the shaft, but how great is the walk of the gear on the shaft.

The gear should walk as little as possible from the 3rd-4th gear clutch and to the stop end on the shaft. Ideally 0.08. 0.2mm.

And the second gear is out of competition. It has developed to such an extent that the development has consumed the sharp edges of the coupling teeth. And this is about a millimeter. It means that the gear shifted on the secondary shaft at least 3.5 mm (second photo) with a tolerance of 0.2 mm. Such a must to the museum!

The teeth on the gear of the first gear are also clogged, so that the second gear will turn on will be very problematic.

The intermediate shaft gear had not beaten teeth and not beaten splines. As a rule, this is always the case. If something has not damaged the teeth of the intermediate shaft, then on the shaft, as a rule, only the bearings are changed. The exception is heavily damaged reverse gear teeth.

The teeth on the reverse gear are jammed. Quite a common defect. It also needs to be replaced, since the wear goes to the taper, the gear may start knocking out after some time. Take a closer look at the larger gear - you can see better from below.

The axle on which the reverse gear rotates looks good. I really don't remember ever changing it.

But the bearing needs to be changed since it is already producing. Roller bearings have the main feature: if the roller fell out of the cage, then the bearing has worn out itself.

Judging by the photos. The croutons were removed from the synchronizer clutch. Nothing surprising. With such a large backlash of the gears (along the shafts), the clutch crackers of the 3rd and 4th gears began to crawl out behind the synchronizer clutch when the gears were turned on. After that, they began to bulge outward under the influence of a spring, and as a result, it was impossible to turn off the gear. Precisely, so that this does not happen, I try to choose all the backlash on the shafts of the box and the inclusion forks when repairing.

Verdict. In the box, you need to change the gear 1,2,3, gears. Also replace the input shaft, all bearings, reverse gear. Not strictly necessary, but requires a hub and both synchronizers. If the new gears dangle on the old shaft more than 0.15mm. (The hand perfectly feels the knock above 0.1 mm.) This means that the secondary shaft should also be replaced.

Yesterday there was such a situation: when the car was moving, there was a crackling and all transmissions stopped working. That is, when you turn on any gear and try to get under way, there is a crunch of gears, and the car does not move. Few people undertake to make these machines, and those who do it have a queue. I'll have to do it myself.

Now I will unscrew the cardan and remove the gearbox. I will try to repair it myself. Unscrewed the box mounting bolts: on one side 2 bolts; on the other side 2 bolts. Put down the pallet. Now I will try to shoot it. So she sagged. That's it, the box is removed.Now I will pull it out and examine it.

I took off the box, now I will disconnect it from the distributor. And immediately that catches the eye - this backlash, the backlash of the input shaft. It still remains a mystery to me how I will put it in its place, but time will tell. I disconnected the box from the distributor, and the second thing that caught my eye was that this nut was unscrewed. And it looks like we have a left-hand thread.

He unscrewed the cover, unscrewed the flange mounting bolts. Now let's see what's inside. I don't see anything dramatic yet. Now I'll see, if anything, I'll tell you. Apparently, this was the problem. This block of gears, this shaft is all shaking, dangling. And here it squeezed out the lid that needs to be screwed on.

Apparently, the problem is in this bearing of the gear block, because the entire shaft sometimes does not mesh, because it dangles. And the synchronizer has practically no teeth. I have a friend, a specialist in VAZ nearby, I will now consult with him and continue the repair.

I consulted with a specialist, they said that both bearings of the intermediate shaft and the bearing of the input shaft are being replaced. They told the ground synchronizer not to touch it, to leave it that way, because there are no rusks or balls. It will work fine. It is also necessary to change the oil sump washer.

I went to the store and bought bearings: 50 208 with a groove on the input shaft; 50 306 to the intermediate shaft. I still need a 305th open bearing without a groove, but there was no open one, I bought a closed one. Then I will remove these rubber things - it will be open. Also, sealant, gaskets for the box, oil squeegees and bolts for the universal joint.

Now we will disassemble the box. To remove the intermediate shaft, these gears must be removed. To do this, I unscrewed this bolt. It must be unscrewed. Now I will knock out the axle. All knocked out.

Now we will knock out the intermediate shaft itself. To do this, we need to unscrew this nut. And you will have to hit the bearing from the other side so that it falls out here. Now let's see how it goes. It was not possible to unscrew this cover, because it was squeezed out, and it did not go along the thread. I just broke it. I don’t know if there are such on sale or not, it is aluminum. Look what happened to the bearing there - practically nothing remained of it.

Now we need to press out the input shaft. Here on the gear there is a place where there are no teeth. It must be placed so that it does not interfere with the exit, so that the teeth do not cling to this gear. We twist, set, now we will press out. I found such an iron screwdriver, I'll put it in now. This input shaft came out very easily.

Let's go further. We pulled out the primary shaft, now we proceed to the secondary shaft. It is necessary to unscrew these bolts, remove this lock washer, and hit the bearing there so that the bearing comes out. I have already unscrewed these plates, which held the bearing in the groove. Now I remove the lock washer, then remove the lock washer. Now you can hit the bearing to make it come out. Now I will press out the bearing with hammer blows. The bearing needs to be pulled out of here, I'll try now. After removing the bearing and removing (inaudible 09:35) washers, I pull out the output shaft.

To remove the intermediate shaft, you need to unscrew this nut and drive it in there. Now let's try how it will be. I unscrewed the countershaft nut, there was a retainer from the bearing, and now we will pull out the gears. He understands everything here and so he should get out. Putting it together so as not to forget how they stood. Now I will wash, clean and start replacing parts and assembling the box. The box has been disassembled, now I will clean this centuries-old dirt with a scraper. Then I'll try, I have a cutter, you can also use a torch, I'll burn it all to keep it clean. Only then will I collect everything.

We install the intermediate shaft. First we put on the ring, then the small gear, then this one will go, the smaller one. Then we put the big one. Only we will insert all this inside, so we will analyze everything again.

Now we will press in bearing 50 306. We press it in on this side, go to the other side. Now we press in the bearing on the other side. We install the secondary shaft. We stuck the rollers on the grease, now we will insert them into the secondary shaft. That's it, there is nothing interesting here yet. Now we will collect everything, connect it to the distributor. The most interesting thing will begin when we put it in place.

Shock! In UAZ "loaf" invested 2 Llamas! What came of it

To insert the box into the distributor, you need to remove the hatch on the distributor and adjust the gears with your hands. It should line up with the output shaft. Using all kinds of pads, I set up the box like this. Now I will try to push it there. I do the work alone, I don't know if it will work out or not. Until the bottom can not put the box, I stuck it in there, but I have not yet hit the clutch. When I was redoing the floors in the loaf, they all rotted away, I foresaw such a hatch, it is held on by bolts. Now I will try to lift it with ropes from here and insert it.

Also look who is going to alter the body of the loaf, I have such a table. I have it that opens on bearings, and there is access to the rear of the engine. Now I will try to lift the box from here. Everything, as we can see, the box went into its mountings. Luke helped, but only two holes would be enough to stretch the rope. That is, I stretched the rope, tied it in a knot, began to twist it with a crowbar, and the box began to rise. I hope I did everything right. Everything, we collect further.

Having twisted a few turns, I lifted the box to the end, and now you can easily tighten the fasteners of the box pillows. So the hatch passed the test - a necessary thing. That's it, finished the work.

It took me 1,500 rubles for the material: for all the gaskets, oil, bearings. Last time I repaired a box in a car service, the first gear took off, they took 10,000 rubles. Today I had to do it myself, but I saved it.

If you are the owner of a UAZ car and there are suspicions about the failure of the gearbox, then you must definitely take on the repair. The unit fails when the driver has to hold the gearshift lever on the move, when they begin to shift by themselves (to prevent this, the drivers tie them up with ropes). Squeaks are sometimes heard.

To get acquainted with the repair technology, read about the repair of the UAZ 452 gearbox with your own hands. First, you need to determine the type of UAZ box that is on the car. Despite the difference between car models, the same transfer cases are installed on them. Therefore, we can assume that repairs are carried out in almost the same way. This will require a set of keys, some tools and aids (listed below).

On most car models of this type, both parts are one piece. The weight of such a unit reaches 75-82 kg, so you need an assistant. If the car being repaired has a safety cage, then you can use a hand winch to remove the UAZ 452 gearbox for repair on your own.

The car must be parked out of the blue, as later it will have to be moved 0.5 m forward or backward. First, the oil is drained. Both boxes have a common volume, but the liquid drain plugs are separate. While the oil is pouring out, you need to remove the front seats and unscrew them, and then remove the halves of the hatch to the floor of the car. Next comes the turn of removing the speedometer rods.

When the oil has drained, screw the drain plugs back into place. There is a frame cross member under the hand brake drum, it must be removed. Disconnect the front axle clutches and unscrew the front universal joint. If you find weakness of the nuts on it, then you need to remove this part.

If the UAZ 3303 gearbox is being repaired, you need to be more careful with the couplings. The car is moved 0.5 m (in any direction) and the rear cardan is removed through the hatch. Disconnect the muffler from the distribution box and loosen the clamp on it.Then, one by one, details such as:

• clutch pallet;
• fasteners for the oiler from the input shaft (it is on the right, on the bell);
• 4 bolts that hold the clutch cover;
• cylinder rod adjustment and fork.

The transfer box is wrapped with rope and hung. The following parts are removed:

• pillow bolts;
• nuts holding the bell box mount.

With these actions, the engine, when the UAZ 452 gearbox is repaired on its own, must be propped up with a jack. When the box is free, it is lowered and taken out from under the car. The levers must first be removed. The pins on the bell must be replaced with new ones.

If you need to repair the UAZ Patriot checkpoint, then it must be borne in mind that the location of the box and the bell is opposite there. This also applies to the position of the rods. But in general, the technology for repairing the UAZ 452 gearbox on its own is suitable for use.

Unscrew the bolts and nuts, disconnect the gearbox and its transfer case. A gasket reinforced with sealant is installed between them, so you will have to hit the bracket for attaching the assembly to the frame several times.

First you need to remove the input shaft cover and unscrew the left nut, which is located on it (see fig.). Now you need to remove its bearing. If it is out of order, it must be replaced. Its roller "brother" is installed inside the shaft, it also needs to be replaced. Then the circlip is removed from the secondary roll. Unscrew the double-row bearing stopper. The shaft must be knocked out and the part changed.

This is followed by the third gear clutch assembly. Copper synchronizers are replaced together with crackers. Then it is the turn of the reverse gear. Unscrew the intermediate shaft front bearing box. Do not hit it with a hammer or core: it is from silumin and may crack.

Be careful not to damage its rubber pad as it is difficult to reach. On the removed shaft, replace the gears and all bearings. After that, assemble the box in the reverse order. When the roller is installed on the input shaft, it is abundantly lubricated with Litol. All units and parts are put in place one by one so as not to be mistaken.

Loosen the nuts of the flanges and shafts, remove them. The hand brake must be checked for operability, if necessary, it must be replaced. Remove all covers and replace the oil seals. Unscrew the drive of the speedometer rods and the breather (it must be replaced). The bearings are checked and replaced if necessary.