DIY gur yumz repair

Power steering repair of the YuMZ (MTZ) tractor - modernization and resumption of work

Power steering repair of the YuMZ, MTZ tractor Part 1

Steering at YuMZ

Alteration of steering YuMZ, pump dispenser, power steering

Power steering repair of the YuMZ, MTZ tractor Part 2

REPAIR OF THE GUR TRACTOR YUMZ, MTZ! IMPORTANT ADDITION.

Yumz 6 power steering after alteration

steering yumz-6 Kormány átalakitás

Power steering YuMZ, Power steering YuMZ, Steering column YuMZ

Replacing the steering column with an MTZ 80 dispenser, my version

Gur YuMZ - MTZ, modernization of the spool + dimensions

my version from gora to dispenser

Repair and modernization of GUR MTZ 80

Buy (price) new power steering YuMZ-6, steering column YuMZ-6, power steering YuMZ-6

Diagnostics, repair and tensioning of the brakes of the YuMZ 6 tractor

New power steering YuMZ, New steering column YuMZ, New power steering YuMZ

Disassembling the steering metering pump

Steering column MTZ spool modernization

Steering with dispenser on T-40

Steering MTZ 80 (washers inserted into the distributor) .wmv

T-40 alteration of the power steering

Old MTZ-82 on the New. Restoration and modernization of the tractor. # SelkhozTehnika_TV # 28

Replacing the steering column with a dispenser in MTZ 80

Installing the dispenser (power steering) on ​​the MTZ tractor. Alteration of steering MTZ-80_82

Installing the dispenser on MTZ 82

Solving problems with the steering column MTZ 82.

Power steering YUMZ-6KL after rework 2.

Power steering mtz-80 dorobotka under the cylinder

Steering column MTZ modernization

- alteration of steering - MTZ-82

Repair of blocking of the MTZ 82 tractor

Do it yourself ☆ GEARS TURN OFF ☆ T-25 ☆ Search for reasons [1h.]

Conversion kit YuMZ 6 for a dispenser pump

Installing the HSS on a homemade tractor

hydraulics pressure regulation МРа

Modernization of MTZ-80 PM installation from Gas-66 (part 1)

worth seeing Tractor T-150 .wmv

Power steering pump work power steering video power steering pump

In order to reduce the effort on the steering wheel when turning the tractor, there is a hydraulic booster. The steering gear ratio with the hydraulic booster is less than without the hydraulic booster, which provides a higher maneuverability of the tractor. The hydraulic booster is installed on the right side of the tractor on an adapter bracket that is attached to the clutch housing. The hydraulic booster is a conventional worm gear steering mechanism, on which hydraulic assemblies are installed: a distributor and a hydraulic cylinder. To increase the tightness of the steering crankcase (to prevent oil leakage from the crankcase), a paronite gasket is installed between the bearing cup and the lock washer, and a copper washer is installed between the lock washer and the nut.

The wobble of the front idler wheels, which is most pronounced when driving at higher speeds, indicates the occurrence of backlash in the steering mechanism or steering gear of the tractor. The most common reason is the loosening of the thrust bearings of the hydraulic booster spool mechanism or their significant wear.

Rice. 1. Diagram of the steering of the YuMZ-6KL tractor with a hydraulic booster: 1 - steering column; 2 - eccentric bushing; 3 - case; 4 - rail; 5 - shims; 6 - emphasis; 7 - finger; 8 - upper cylinder cover; 9 - stock; 10 - piston; 11 - bottom cylinder cover; 12, 27 - bolts; 13 - bipod; 14 - lock nut; 15, 18 - springs; 16 - screw; 17 - safety valve; 19, 28 - covers; 20 - spherical nut; 21 - spool; 22 - distributor body; 23 - plunger; 24 - worm; 25 - sector; 26 - oil discharge line; 29 - oil pump; 30 - oil suction line; 31 - oil drain line; 32 - oil tank; 33 - filter; 34 - drainage oil line; 35 - pedal; 36 - clamp

Rice. 2. Determination of the convergence of the guide wheels: 1 - longitudinal thrust; 2 - pushing rod; 3 - transverse thrust

Difficulty turning the guide wheels in only one direction indicates a malfunction of the valve spool pair of the distributor or the power cylinder.

In one case, chips or deep scratches appear on the annular protrusions of the spool or distributor housing, through which oil flows out when the steering wheel is turned. In another, for example, when the steering wheel is turned to the right, it is difficult to turn the destruction (break or break) of the rubber seal of the piston rod of the power cylinder. This does not create a piston back pressure due to large oil leaks through a defective seal in the power steering housing. In the first case, the hydraulic booster distributor assembly is replaced with a new one, in the second, the hydraulic booster is partially disassembled to replace the rubber seal in the lower cover of the power cylinder.

A large effort applied to turn the steering wheel can occur when: a decrease in the performance of the high-pressure hydraulic pump, a misalignment of the safety valve, in the event of large oil leaks in the power steering mechanisms, in case of front malfunctions.

Rice. 4. Connecting the pressure gauge to the hydraulic booster: 1 - cap: 2 - fitting; 3 - lock nut; 4 - safety valve

Steering of the YuMZ tractor includes a power steering, a column with a steering wheel, a longitudinal link and a steering linkage of the front axle.

Steering gear YuMZ is a worm gear that interacts with hydraulic units: a hydraulic cylinder and a distributor. The mechanism is mounted in a separate housing attached to the clutch housing on the right side of the tractor.

The gearbox consists of a worm connected by a cardan transmission to the steering wheel, and a sector with a rotary shaft. When the steering wheel rotates, the force from the steering shaft is transmitted to the bipod and then through the longitudinal rod to the steering linkage of the front axle.

To reduce the effort on the steering wheel when turning the tractor, it is designed power steering yumz... The steering gear ratio with the hydraulic booster is less than without the hydraulic booster, which leads to a higher maneuverability of the tractor. The hydraulic booster consists of a pump, a distributor and a hydraulic cylinder.

Steering control of the YuMZ tractor: 1 - clamp; 2 - steering column; 3 - bolt; 4 and 21 - covers; 5 - drainage oil line; 6 - oil tank; 7 - oil drain line; 8 - filter; 9 - oil suction line; 10 - pump; 11 - oil discharge line; 12 - worm; 13 - plunger; 14 - safety valve; 15 - lock nut; 16 and 20 - springs; 17 - screw; 18 - distributor body; 19 - spherical nut; 22 - spool; 23 - sector; 24 - bipod; 25 - bottom cylinder cover; 26 - piston; 27 - stock; 28 - upper cylinder cover; 29 - finger; 30 - emphasis; 31 - shims; 32 - rail; 33 - case; 34 - eccentric bushing.

In power steering, the worm is installed in an eccentric bushing on two radial ball bearings.The bearings are installed in the bushing with a small clearance, so the worm, together with the distributor spool attached to its shank, has the ability to move in the axial direction. On both sides of the spool, thrust ball bearings are installed, which provide axial movement of the spool and prevent it from rotating with the worm. Bearing races facing the spool have larger outer diameters and act as centering washers. The ball nut pushes the bearings against the spool.

The sector is simultaneously in engagement with the worm and the rail connected by a pin to the cylinder rod. When the tractor is moving in a straight line, the spool is in the neutral position and is held by three pairs of plungers located at an angle of 120 °. The plungers are moved apart by centering springs and therefore tend to keep the inner bearing races connected to the spool flush with the ends of the steering housing and distributor cover.Oil from the pump flows through the oil line to the central collar of the spool and, since the width of the collar is less than the width of the groove on the distributor housing, it bends around it, flows into the extreme drain grooves and then through the oil line through the filter is drained into the tank.

When the tractor turns to the left, the rotation of the steering wheel is transmitted to the worm through the cardan transmission. If the resistance to turning of the guide wheels is large, an axial force arises on the worm, which will exceed the compression force of the centering springs. The worm, resting on the sector braked by the resistance of the wheels, like a screw in a fixed nut, will move together with the spool attached to its shank down to the cover. In this case, the middle belt of the spool will block the passage of oil from the pump to the lower drain groove. At the same time, the upper collar of the spool will block the oil outlet from cavity A of the cylinder to the upper drain groove on the distributor housing.

The other extreme (lower) collar of the spool, on the contrary, will increase the flow area for draining oil from the cavity B of the cylinder into the groove on the distributor body. The oil from the middle discharge groove will go through the pipeline into the cavity A of the cylinder. The piston, together with the rod and the rack, will move and, acting on the sector, will turn the shaft and bipod forward along the direction of the tractor. The bipod through the rods and levers of the steering linkage will turn the guide wheels to the left. The idler wheels on the tractor will turn as long as the steering wheel turns. Moreover, the turning speed of the tractor wheels is proportional to the angular speed of the steering wheel. As soon as the rotation of the steering wheel stops, the spool is returned to the neutral position by the action of the plunger springs. Turning to the right is carried out in the same way.

If the resistance to turning the wheels is insignificant, then the turning is carried out without the participation of the hydraulic booster. In this case, the axial force on the worm, which occurs when the tractor is turning, is less than the pre-compression force of the centering springs of the plungers. Turning the steering wheel provides a direct transfer of movement to the steering link from the worm through the sector, shaft and bipod. In this case, the centering springs are not compressed, the worm, together with the spool, does not move in the axial direction, the oil in the distributor from the discharge cavity overflows into the drain cavity without affecting the cylinder piston. In this case, the sector moves the rod and the piston of the cylinder through the rail, and the oil from the cavities A and B is drained into the tank.

Oil pump Power steering YUMZ 6 is located on the left side of the diesel engine, coaxially with the pump of the tractor hydraulic system and receives rotation from the diesel engine timing gears. A safety valve is attached to the distributor housing, which prevents the pressure in the hydraulic system of the amplifier from increasing in excess of the permissible value. The safety valve is adjusted to a pressure of 8 MPa (80 kgf / cm2) by rotating the screw, which rests on the spring, which, after adjustment, is locked with a lock nut. To improve locking and ensure tightness, a cap is screwed onto the screw.

For ease of control, the upper part of the steering column of the yumz is made swinging. The tilt of the steering column is fixed in four positions by a detent controlled by a pedal located below the steering column.

To change the height of the steering wheel, unscrew the clamp by three to five turns, set the steering wheel to a position convenient for the driver and tighten the clamp until the steering shaft is locked. The height of the steering wheel is adjustable within 120 mm.

(097) 056-05-93, (099) 429-92-85, (093) 651-44-42

If the article didn’t finish, you cannot, if you don’t want to repair the power steering YuMZ, then trust our fahivtsy. For repair of the steering column YuMZ (GUR YuMZ), call (096) 859-54-47

If the article didn’t finish, you cannot, if you don’t want to repair the power steering YuMZ, then trust our fahivtsy. For repair of the steering column YuMZ (GUR YuMZ), call (096) 859-54-47

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Better yet, put a dispenser with a cylinder.And forget forever where this power steering is located.

Better yet, buy a new MTZ for two hundred thousand. )
I wrote that this topic was created to help people who faced this problem like me, and who at the moment have only one way out, to repair what they have. There is one more problem in Ukraine - it is legal to undergo a technical inspection of a tractor with a dispenser, it is impossible at the YuMZ-6.
If users think that this topic is superfluous, let the moderators remove it.

How many tried to repair these gurus, nothing good came of it. New ones do not always work well either. But the dispenser is a thing. And if you put a kit from a new UMZ, you will not pass the technical inspection either?

And it doesn't matter, we call it “re-equipment”, you have to go to the factory or look for some company that has permission, take a certificate from them that they either give permission for such a change in this model or that they did the installation ... In any case, it is money and time.

So can I get a certificate? I don’t think it’s expensive. I have a dispenser at YuMZ with KUHN. With a full bucket of sand (about 800 kg), the steering wheel quietly turns with one cookie without any effort.

With a full bucket of sand (about 800 kg), the steering wheel quietly turns with one cookie without any effort.

I believe. For me, too, everything now works and turns. I needed it now and at the lowest cost, which I did, and this is the dispenser in the future, if possible. My repair costs were 20 grams. and the dispenser will be installed more than 3000 gr. This is the arithmetic.

Guys! Tell me how to put the cuff (and in general how it looks) on the YUMZ-6 power steering piston. I bought a repair kit, I did not understand why plastic rings are needed. If you can take a photo or drawing. For two days I have been using the Internet and the forum, I remember that it was somewhere, but I cannot find it.

Kuzma70. there is no cuff. There should be three rings, one rubber and two plastic. The rubber one stands in the middle between the plastic ones. Some say that in order to put on plastic rings, they must be heated in water, others say that they need to be cut at an angle, tried on and cut if necessary, and I myself saw that there were cut plastic rings in the factory hydraulic cylinders. My groove was already bored out for two rubber rings, without plastic ones, such know-how.

Many thanks! Now something began to clear up, when I disassembled the piston, there was nothing at all, and in this state we drove it over 100 km. Thanks again!

Kuzma70, there is nothing for that, contact, how I can help.

Hello Yuriy1598! It so happened that he returned to the repair of the gur quite recently. I will share a little experience. The plastic rings are easy to put on the piston after 2-3 minutes of boiling using a flat screwdriver. I put it in the following order: square ring - rubber ring - square ring. Perhaps the order of installation does not matter, but it seemed that the rubber ring would be difficult to squeeze between the well-shrunk plastic ones. But there is also a problem. After installing the gura, the bipod does not sit on the shaft, the teeth become almost opposite. Maybe I put together something wrong. Please, tell me.

gur installation - the bipod does not sit on the shaft, the teeth become almost opposite. Maybe I assembled something wrong. Please, tell me.

Maybe I'm wrong, but it seems like there is one slot larger in size, and the bipod will only be put on if it is correctly combined.

gur installation - the bipod does not sit on the shaft, the teeth become almost opposite. Maybe I assembled something wrong. Please, tell me.

Maybe I'm wrong, but it seems like there is one slot larger in size, and the bipod will only be put on if it is correctly combined.

I put it in any position.

yuriy1598, thanks for the topic, it's a pity you haven't come here for 38 weeks. It also doesn't spin well in the left one, or doesn't want to at all. So I'm not the only one! About the puck I didn't understand a little how and where it was, it's a pity nobody posted the pictures. I will do it myself, so I will record it.

but how to understand that the pump or distributor is covered on the hinge?

or rather, how to check if the pump is working without having a spare? covered the hinge does not rise sorry what we wrote here, who knows

or rather, how to check if the pump is working without having a spare? covered the hinge does not rise sorry what we wrote here, who knows

try on the distribution valve, which under the cover with 2 bolts to remove, look, maybe something got under it, or stuck it. There is a separate topic "YUMZ hydraulics"

Gentlemen, do not litter this topic, go to the topic of hydraulics, and ask there.

yuriy1598, thanks for the topic, it's a pity you haven't come here for 38 weeks. It also doesn't spin well in the left one, or doesn't want to at all. So I'm not the only one! About the puck I didn't understand a little how and where it was, it's a pity nobody posted the pictures. I will do it myself, so I will record it.

if it does not turn to the left, it may be due to the cylinder rod ring. Check when turning to the left does not the oil go from the column crankcase to the return line (plastic tube)?

if it does not turn to the left, it may be due to the cylinder rod ring. Check when turning to the left does not the oil go from the column crankcase to the return line (plastic tube)?

Thank you, here I will throw off the power steering (replacement of the dry block), I'll take a look.
The question is, there are power steering repair kits only for MTZ, but the sellers (not confidently) said they in 1: 1 and to YuMZ, is this so?

if it does not turn to the left, it may be due to the cylinder rod ring. Check when turning to the left does not the oil go from the column crankcase to the return line (plastic tube)?

Thank you, here I will throw off the power steering (replacement of the dry block), I'll take a look.
The question is, there are power steering repair kits only for MTZ, but the sellers (not confidently) said they in 1: 1 and to YuMZ, is this so?

Spool, valve and piston 1: 1.

if it does not turn to the left, it may be due to the cylinder rod ring. Check when turning to the left does not the oil go from the column crankcase to the return line (plastic tube)?

Thank you, here I will throw off the power steering (replacement of the dry block), I'll take a look.
The question is, there are power steering repair kits only for MTZ, but the sellers (not confidently) said they in 1: 1 and to YuMZ, is this so?

yes, the inner part, the hydraulics are the same. and the flow from the return should be looked at as it was started (still post 3741 in the subject Yumz EO2621 read it - just wrote)

Thanks colleagues, I will sort it out, I will write in the subject, what happened after all.

check in. I went into this topic at the request of a friend, he is suffering with a gur. did not know that the spool with Belarus and Yumzovsky are identical. Recently in Belarus they did a similar thing. the steering wheel turns with a finger, even with a full bucket of rubble. Well, I stupidly welded on the spool on both sides pieces of pipes 2 2.5 mm of a suitable diameter. does it mean that you can do the same thing on yumaz?

Steering control of tractors YuMZ-6AL and YuMZ-6AM

Steering consists of a steering gear, a column with a steering wheel, a longitudinal link, levers and a steering linkage. The steering mechanism is mounted in a separate housing 3 (Fig. 49), attached on the right side to the clutch housing, and consists of a worm 24 and a sector 25 with a rotary shaft. The torque is transmitted from the pivot shaft to the bipod 13 and further to the steering linkage rods. The parts of the steering mechanism are made with great precision, are very durable and require adjustment only after a long mileage.

A hydraulic booster is designed to reduce the effort on the steering wheel when turning the tractor. The steering gear ratio with the hydraulic booster is less than without the hydraulic booster, which leads to a higher maneuverability of the tractor. The hydraulic booster is installed on the right side of the tractor on an adapter bracket that is attached to the clutch housing. The hydraulic booster is a conventional worm gear steering mechanism, on which hydraulic assemblies are installed: a distributor and a hydraulic cylinder.

To increase the tightness of the steering crankcase (to prevent oil leakage from the crankcase), a paronite gasket is installed between the bearing cup and the lock washer, and a copper washer is installed between the lock washer and the nut.

Rice. 49. Power steering diagram:
1 - steering column; 2 - eccentric bushing; 3 - case; 4 - rail; 5 - shims; 6 - emphasis; 7 - finger; 8 - upper cylinder cover; 19 - stock; 10 - piston; 11 - lower cylinder cover: 12, 27 - bolts; 13 - bipod; 14 - lock nut; 15, 18 - springs; 16 - screw; 17 - safety valve; 19, 28 - covers; 20 - spherical nut; 21 - spool; 22 - distributor body; 23 - plunger; 24 - worm; 25 - sector; 26 - oil discharge line; 29 - oil pump; 30 - oil suction line; 31 - oil drain line; 32 - oil tank; 33 - filter;
34 - drainage oil line; 35 - pedal; 36 - clamp

The hydraulic distributor oil pump is located on the left side of the engine, coaxial with the hydraulic pump

of the tractor and receives rotation from the timing gears of the engine. A safety valve 17 is connected to the distributor housing 22, which prevents the increase in pressure in the hydraulic system of the booster in excess of the allowable one. The safety valve is adjusted to a pressure of 8 MPa (80 kgf / cm2) by rotating the screw, which rests on the spring, which, after adjustment, is locked with a lock nut. To improve locking and ensure tightness, a cap is screwed onto the screw.

The upper part of the steering column can be tilted forward for the convenience of the driver approaching the seat or exiting the cab. When you return the column to its original position, the latch locks into place automatically.

To change the height of the steering wheel, unscrew clamp 36 by 3-5 turns, set the steering wheel to a position convenient for the driver and tighten the clamp until the steering shaft is locked. The position of the steering shaft in height is adjustable within 120 mm.

Below is the technical characteristics of the power steering.

Power steering type. Separate-aggregate

Pump type. Gear NSh-10U

Direction of rotation of the pump. Right (when viewed from the drive side)

Pump flow rate, l / min. Not less than 14

Cylinder. Double-acting, piston diameter 90 mm

Distributor. Single spool, tracking type

Working fluid. Oil: in winter М-8В2, in summer М-10В2

Belarus tractors MTZ-80, MTZ-82, MTZ-82.1, MTZ-1221, 1523, MTZ-892, YuMZ, T-40. Agricultural machinery: plows, cultivators, walk-behind tractors, mowers, seeders

SPARE PARTS FOR TRACTORS

ADJUSTMENT OF MTZ TRACTORS ___________________

DIESEL ENGINE PARTS ___________________

SPARE PARTS CATALOGS MTZ ___________________

TECHNICAL CHARACTERISTICS OF TRACTORS ___________________

SPECIAL EQUIPMENT BASED ON MTZ AND ATTACHED EQUIPMENT ___________________

AGRICULTURAL MACHINERY AND EQUIPMENT ___________________

The steering gear of the YuMZ tractor is mounted in housing 9 (Fig. 17), which is installed on the right side of the clutch housing and is held on it by two pins and four bolts.

Rice. 17. Steering gear of tractors YuMZ

1 - steering wheel; 2 - signal button; 3 - steering column: 4 - worm: 5 - adjusting shims: 6 - bipod shaft: 7 - longitudinal thrust; 8 - bipod; 9 - case; 10 - roller; 11 - steering shaft; 12 filler plug; 13 - insert; 14 - spring; 15 adjusting plug; 16-adjustment screw; 17 washer; 18 - nut-cap; 19 - bearing glass

The body is made in the form of a shaped iron casting. A number of boring holes are made in the body, which include parts of the YuMZ steering mechanism.

The main parts of the steering mechanism (gearbox) of the YuMZ - a ridge roller and a globoidal worm 4, make up a worm pair with a gear ratio of 23.5: 1.

Inside the worm there are fir-tree splines, with the help of which it is mounted on similar splines of the steering shaft 11. The worm rests on two tapered bearings installed in the bores of the housing.

The bearings do not have an inner ring and their rollers roll directly on the tapered surfaces of the worm. The outer bearing races are axially clamped by covers.

Under the flange of the bottom cover, cardboard shims 5 are installed, which are used to adjust the axial clearance of the bearings. The upper cover is the base of the steering column 3, which is pressed into the cover bore with its lower end.

The three-ridge roller of the YuMZ steering mechanism rests on two needle bearings, which are placed on an axle pressed into the holes of the tide (head) of the bipod shaft.

On both sides of the roller there are thrust washers with flats, which prevent the washer from turning relative to the bipod shaft lugs. Thrust washers protect the roller ends from wear and limit the axial play of needle bearings

Shaft 6 of the YuMZ steering gear (reducer) bipod rests on the outside on a bushing pressed into the side cover, and on the inside on a cylindrical roller bearing installed in glass 19. The inner bearing ring is hot pressed onto the bipod shaft journal.

The inner end of the bipod shaft has an annular groove that fits into the groove of the adjusting screw 10. A hexagonal recess or a milled groove for a special key is made at the end of the screw on the reverse side.

The adjusting screw is screwed into the roller bearing cup and keeps the bipod shaft of the YuMZ steering mechanism from axial movements.

It is locked with a washer 17, which with its mustache enters the screw groove, and with its recess into the pin pressed into the glass. A nut 18 is screwed onto the screw, which presses the washer to the glass.

The adjusting screw can move the bipod shaft in the axial direction and thereby change the gap between the worm and the roller, which affects the free play of the steering wheel.

If the adjusting screw is tightened all the way, then the ridges of the roller will rest against the worm, that is, there will be no gap between the roller and the worm.

In this position, the roller axis of the new YuMZ steering mechanism is displaced relative to the worm axis by 6 mm.

The outer end of the bipod shaft has fir-tree slots on which the bipod is put on 8.

For the correct installation of the bipod on the steering mechanism shaft of the YuMZ, risks are knocked out on their ends, the alignment of which corresponds to the location of the bipod 5 ° forward from the vertical when the roller is aligned with the middle of the worm.

The bipod is fastened with a nut on the shaft and tightened during operation.

To lubricate the parts, the YuMZ steering gear case is filled with transmission oil to the level of the filler hole, which is closed with a plug 12.

Self-tightening gland, felt ring and cardboard gaskets prevent oil from leaking out of the housing.

The steering parts of the YuMZ, connecting the bipod with the pivot pins, make up the steering drive.

At the lower end of the bipod in a tapered hole, a ball pin rod is fixed, the sphere of which is located in the longitudinal steering rod 7.

On both sides of the ball pin there are liners 13, which are pressed against it by spherical recesses by means of a spring 14 placed on the stop and clamped in the steering rod by a threaded plug 15.

A similar ball joint connects the front end of the longitudinal tie rod with the steering lever of the YuMZ tractor. The rest of the drive parts are reviewed and shown in fig. eighteen.

When the steering wheel of the YuMZ is turned clockwise (to the right), the worm turns the lower end of the bipod back through the roller.

The bipod turns the steering wheels to the right through the longitudinal link and the steering linkage connected to it. Turning to the left is carried out in the same way.

The steering of tractors YuMZ-6, YuMZ-6 AM, YuMZ-6 KL, YuMZ-6 KM differs from the steering YuMZ by an adjustable steering column (in height and angle of inclination) and by the presence of a hydraulic booster made in the same body with the steering gear.

Rice. 18. Diagram of steering with power steering (GUR) tractors YuMZ-6

1 - steering column; 2 - eccentric bushing; 3 - case; 4 - rail: 5 shims; 6 - emphasis; 7 - finger; 8 - upper cylinder cover; 9 - stock; 10 - piston; 11 - bottom cylinder cover; 12, 27 - bolts; 13 - bipod; 14 - lock nut; 15, 18 - springs; 16 - screw; 17 - safety
valve; 19, 21 - covers; 20 - spherical nut; 21 spool: 22 - distributor housing; 23 - plunger,24 - worm; 25 - sector; 26 - oil discharge line; 29 - pump; 30 - oil suction line; 31 - oil drain line: 32 - tank; 33 - filter; 34 - drainage oil line; 35 - pedal; 36 - clamp; A and B - cavities

The oil pump of the hydraulic distributor is installed on the left side of the engine coaxially with the pump of the hydraulic system of the YuMZ tractor and receives rotation from the engine distribution gears.

A safety valve 17 is connected to the valve body 22 (Fig. 18), which prevents the pressure in the hydraulic system of the booster from increasing in excess of the permissible value.

The safety valve is adjusted to a pressure of 8 MPa by turning the screw, which abuts against the spring, which, after adjustment, is locked with a lock nut.

To improve locking and ensure tightness, a cap is screwed onto the screw.

For the convenience of the operator's approach to the seat or when it leaves, the upper part of the UMZ steering column can be tilted by first pressing the pedal 35.

When you return the column to its original position, the latch locks into place automatically.

To change the installation of the YuMZ steering wheel in height within 120 mm, it is necessary to unscrew the clamp 36 by 3-5 turns, set the steering wheel to a position convenient for the operator and tighten the clamp until the steering shaft is locked.

The tractors YUMZ-8070, YUMZ-8280 are equipped with a HSS with an autonomous hydraulic system with a working volume of 5.5 liters of oil.

The principles of operation of the hydraulic booster and the power steering are similar to the MTZ-80, MTZ-82, MTZ-100 and MTZ-102 tractors.

Steering adjustment of YuMZ tractors

Steering YUMZ without power steering (GUR)

The normal free play of the YuMZ steering wheel during straight-line movement of the tractor should not exceed 15 °.

If it is above 30, then you need to adjust the steering.

First, the pivot joint of the YuMZ steering rods and the clearances in the tapered bearings of the guide wheels are adjusted.

If the free play of the steering wheel of the YuMZ tractor then remains increased, check the axial clearance in the tapered bearings of the steering gear worm.

To do this, disconnect the longitudinal link from the bipod and remove the worm from engagement with the roller by rotating the steering wheel in any direction.

Then the steering wheel shaft of the YuMZ is shaken in the axial direction.

If the movement of the shaft is noticeable, the clearance in the tapered bearings of the worm is reduced by removing some of the shims 5 from under the lower cover of the steering gear.

With the correct adjustment of the worm bearings, the steering wheel should rotate with hand force.

After that, set the roller against the middle of the worm and, shaking the bipod, check the gap between the roller and the worm.

The normal clearance should be such that the lower end of the bipod moves no more than 0.15 mm when swinging.

If the gap is larger, then it must be adjusted.

Adjust the engagement of the worm with the roller in the following sequence.

Remove the steering gear of the YuMZ, unscrew the nut of the adjusting screw and remove the lock washer.

Tighten the adjusting screw until there is no gap in the engagement when the roller is positioned against the middle of the worm, and the steering wheel turns from a force of 15-22 N.

Then put the lock washer in place, secure it with a nut and put the steering gear on the tractor.

Steering YUMZ with power steering (GUR)

The gap in the worm-sector engagement should correspond to the gap on the side surface of the worm splines with the middle position of the bipod 0.6-0.7 mm (angle 4-6 °).

To adjust it, unscrew the bolt 2-3 turns and turn the bushing clockwise to reduce the gap or counterclockwise to increase it.

After adjustment, the bolt is tightened.

The gap on the teeth between the sector and the rack should correspond to the gap of 0.1-0.3 mm between the mating plane of the stop flange 6 and the body 3.

The gap is set by selecting shims.

To determine the thickness of the gaskets, the gap between the attachment planes of the stop and the body is determined with a gap-free engagement of the rail with the sector.

The thickness of the spacers should be 0.1-0.3 mm thicker.

Free travel of the pivot shaft in the axial direction is controlled by a screw in the steering gear housing.

To do this, release the screw locknut and turn it all the way, then turn it back 1 / 10-1 / 8 of a turn and lock it with a locknut.

For normal operation of the power steering power steering YUMZ, it is important to correctly tighten the thrust bearings with a spherical nut.

Over tightening the nut can cause the spool to tilt and increase turning force.

Before tightening the nut, the distributor is fixed on the YUMZ power steering housing with two bolts, after placing washers under the head of the bolts to the thickness of the cover flange 19.

Tighten the worm nut with a torque of 20 Nm, unscrew it by 1 / 12-1 / 8 of a turn until the hole in the worm aligns with the slot for the cotter pin and cotter the nut.

Then, the two bolts securing the distributor to the housing are unscrewed, the cover 19 is installed and the distributor is securely fixed to the hydraulic booster.

Adjustment of the safety valve is similar to the adjustments of the MTZ-80 and MTZ-82 tractors.

When adjusting the steering rod joints of the YuMZ tractor, unpin the adjusting plug, screw it all the way in, and then unscrew it until the groove of the plug coincides with the holes for the cotter pin in the rod and cotter it.

When adjusting the hinges of the lateral and pushing steering rods of the YuMZ, unpin the adjusting plug, then screw it in so that the ball pin turns in the liners when a torque of 3-7 Nm is applied.

Steering adjustment of tractors YuMZ-8070, YuMZ-8280

The oil in the HSU system of the YuMZ tractor must be changed during seasonal maintenance, and if the system is filled with off-season oil, every 1000 engine hours of engine operation.

The filter element of the HSU must be changed every 500 hours of tractor operation.

Rice. 19. Oil change in the HSS tractors YuMZ-8070, YuMZ-8280

1 - cover; 2 - tank; 3 - drain plug; 4, 7 - oil pipelines; 5 - bolts; 6 - filter

To change the oil and filter element, proceed as follows:

- turn the steering wheel to the extreme right position until it stops;

- remove the cover 1 (Fig. 19), unscrew the plug 3 and drain the oil from the tank 2;

- disconnect two bolts 5 of fastening the filter to the bracket and remove the filter;

- unscrew the remaining two bolts, fastening the filter to the bracket, and remove the cover;

- remove the filter element with a bypass valve from the housing.

It is prohibited to rotate the body of the bypass valve along the thread, as this will disrupt its adjustment;

- flush the filter housing and bypass valve, replace the filter element;

- assemble and install the filter on the YuMZ-8070, YuMZ-8280 tractor, connect the oil lines to it;

- pour oil into tank 2 up to the level of the upper mark on the oil meter;

- start the engine and turn the steering wheel several times to the left and right until it stops;

- stop the engine and add oil to the tank with the steering wheel in the middle position;