Installing a dispenser on an old model MTZ 82. The operating principle and nuances of installing a metering pump at MTZ. This picture can be observed either when the oil level is insufficient, which does not allow the metering pump to effectively perform its functions, or when the oil level is excessive.

The hydraulic power steering (power steering) MTZ-80, MTZ-82 is combined with the steering mechanism. Their purpose is to transmit and increase force from the steering wheel, drive to the bipod and steering linkage swing arms, and thereby reduce the force on the steering wheel. Power steering strengthens the control system, while the tractor driver needs to make significantly less effort to turn the wheels. This point is of particular importance if the tractor is heavily loaded and the power steering copes with this task, unless, of course, it is in working order. Over time, equipment components wear out, especially if the tractor has had several owners. It happens that it is impossible to repair your original power steering, in these cases we install a dispenser. The dispenser is a hydraulic volumetric steering system; it performs the same functions as power steering. You can watch the installation of the dispenser in my video. I showed an example of installation on a tractor with a front rolling beam, where the factory does not provide for the installation of a hydraulic cylinder, there is not even a casting (the casting is the surface into which the hydraulic cylinder is screwed). In this case it will not suit usfactory cylinder mounting bracket. We will need to make it ourselves, and also drill and cut M16 threads on the beam. More detailed information can be obtained from the link “Step-by-step instructions for manufacturing an MTZ cylinder mounting plate.” Here is a description with dimensions and photographs that will help you quickly make a hydraulic cylinder mounting plate.

If the power steering is working, but the steering wheel is difficult to rotate. I recommend reading my article

Homemade hydraulic cylinder mounting plate when installing the dispenser on the MTZ-80-82 tractor.

List of required parts.

1. We make an MTZ bracket for installing a hydraulic cylinder
on one's own.

2. Bracket for the metering pump to the MTZ HAS

3. Steering rod MTZ with mount hydraulic cylinder 1220-3003010

4. Steering lever MTZ left with mount 72-2308075-01

5. Steering lever MTZ right with mount 72-2308074

6. Steering hydraulic cylinder MTZ TsS 50-3405215 (equipped with pins and fittings for connecting the high pressure hose.)

7. MTZ dispenser pump for connecting the steering shaft

8. Hydraulic hoses high pressure with knees at L-90 degrees . mustache (4 pcs.) MTZ fittings - 4 pcs

9. Hydraulic tank

Restoration of the axle, description of the front beam of the MTZ tractor, about this in my article

Connection diagram for the dispenser pump.

Description of the installation of the metering unit (GRU) of the MTZ tractor.

On the steering column bracket there is a metering pump, which is connected to the oil pump using a hydraulic hose. The rotary cylinder is mounted on the front beam to homemade stove. It is connected by a dispenser with two hydra hoses, left and right turning. At the other end, the cylinder is secured with a conical threaded pin with a lever, which subsequently gives turning movements through other levers to the tractor wheels. Exit - unloading from the dispenser with a hydra hose connected to the oil tank.

Operating principle.

When the engine is running, oil is transferred to the metering pump thanks to the NSh oil pump. During the straight-line movement of the tractor, both cavities of the rotary hydraulic cylinders are blocked by spool belts, due to which the oil pumped by the NSh feed pump and directed to the dispenser is not distributed by it, but is redirected to the oil tank. By turning the steering wheel to one side, the displacement of the spool causes the oil to enter the metering pump, which transfers it in an amount proportional to the angle of rotation of the steering wheel to the corresponding rotary cylinder. This promotes the use of left or right rotary mechanism and turning the guide wheels in the desired direction.

Design of the metering pump

The design of the metering pump is quite simple, which provides it with high fault tolerance and a long operating period. Its design includes:

housing with valve block (check valves, shockproof, anti-vacuum, safety);
swing unit;
distributor.

The swinging axial piston unit has in its design a stator attached to the housing, as well as a rotating rotor, which is connected to the spool. The spool itself is in contact with the steering shaft, thanks to the rotation of which it can move in an axial position, allowing oil to enter the metering pump. The neutral position of the spool is ensured by two locking springs.

Thanks to the operation of the check valve, the drain accumulator line is blocked when the power unit is not working. System safety valves provides limitation of the maximum pressure in the oil discharge lines. It should not go beyond 14 MPa.

The presence of anti-shock valves will limit the pressure in the oil lines of the GRU cylinders under shock load. These valves are designed to control pressure at 20 MPa. Anti-vacuum valves guarantee the possibility of supplying oil to the hydraulic cylinders of the system in the event of emergency situation, as well as when one of the shock valves is triggered.

Characteristic signs of malfunctions of the MTZ dispenser (GRU).

The occurrence of malfunctions in the operation of the hydraulic steering system of the MTZ "Belarus" can be directly observed in the process of operating the equipment. The main features include the following factors.

Difficult to control (more physical effort is required to turn the steering wheel)

This type of problem occurs when oil leaks from the system or its level is insufficient. Also, such a picture will be observed when the air pump is pumped and the feed pump is poorly driven from the tractor engine.

Instability of guide wheels

This malfunction is mainly associated with excessive axial movement of the rotary shaft or the appearance of play in the steering rods.

Missing stop when turning the steering wheel

This picture can be observed either when the oil level is insufficient, which does not allow the metering pump to effectively perform its functions, or when the seals of the rotary hydraulic cylinders are excessively worn.

Spontaneous rotation of the steering wheel

This breakdown is associated with the failure of the metering pump spool to return to the neutral position and, as a result, the constant operation of one of the rotary cylinders.

Inconsistency between the right/left steering wheel turn and the corresponding wheel turn

This can be observed after replacing or repairing the metering pump, during which the pump leads were incorrectly connected to the inputs of the rotary cylinders when the second one was not working.

Installation of a metering pump at YuMZ today is not something unknown. On the contrary, this topic has been relevant for several years now. Developed and compiled special conversion kits, thanks to which the installation process is greatly simplified. On the Internet you can find a lot of information, suggestions and comments, how to convert YuMZ to GORu correctly, and most importantly high quality.

Re-equipment of the YuMZ steering control can be divided into two types. The first is the re-equipment of YuMZ tractors with a large cabin, and the second - with a small one.

For these purposes, our online store offers two different ones.

The first one is for YuMZ with large cabin, includes the following spare parts:

Bracket for installing a metering pump

· Shaft-cup of the dispenser pump

The second one is for YuMZ with small cabin, includes:

· Metering pump (complete with 4 fittings)

Hydraulic cylinder (complete with 2 pins and 2 fittings)

· High pressure hoses (4 pieces)

· Central lever for hydraulic cylinder

The price of the first set is 4600 UAH, and the cost of the second is 42 00 UAH

When purchasing a small set, you can purchase it with a 25% discount, and it will cost you around 300 UAH.

Also available in our online store hydraulic tank YuMZ, which is used as an element separate from the main hydraulic system. It provides power to system consumers MOUNTAIN tractor YuMZ.

You can also separately from the kit. Its cost is 650 UAH.

Having decided on the component materials, we proceed directly to the conversion.

The conversion process itself - remove the power steering (power steering), install a bracket for installing the hydraulic steering in its place and screw it with four bolts, connect the shaft from the steering wheel.

Next, to attach the hydraulic steering wheel you will need to use a glass shaft. Replace the central lever, install the wheel steering hydraulic cylinder (it comes complete with pins and fittings). Using high-pressure hoses, connect the metering pump to the NSh pump and the hydraulic cylinder.

Let's look at one example of installing a metering pump on a YuMZ tractor with a small cabin. In the first diagram we see “Installing a hydraulic cylinder”:

In the figure you can see that the hydraulic cylinder, using fingers, connects the lever to the axle beam.

Below we provide a diagram hydraulic connection dosing pump.

The metering pump can be installed in the tractor cabin or under it. Both options are shown in the photographs below.

In the cabin:

Installing a metering pump under the cab:

If it is expensive for you, or you do not need to buy the entire conversion kit, then we can offer you the sale of spare parts separately. There are situations when the buyer already has some of the materials for converting the tractor, and only some are missing.

In some cases, the guys use improvised means, for example, one of our site visitors, instead of a shaft-cup for a metering pump, used a pipe from a motorcycle clutch box, which he kindly shared in the comments. Someone has perfect “welding art” and can weld some parts from the kit themselves, and other options.

One of the frequently asked questions after installing the hydraulic steering wheel is that the steering wheel is a bit stiff and there is no sharpness in steering. This most likely indicates incorrect installation or connection of components. Check everything again.

Often, installation of a metering pump (hydraulic steering wheel) on the YuMZ tractor evokes only positive responses.

If you have any questions, write in the comments, we will always be happy to help.

The MTZ metering pump is an integral part of the tractor's hydrostatic control system. He is responsible for the correct distribution of fluid in the system and for its supply to the hydraulic cylinders. This strengthens the control system.

In this case, the operator needs significantly less effort to turn the wheels. This point is of particular importance if the tractor is heavily loaded.

1 Design and principle of operation of the metering pump at MTZ

The MTZ metering pump is manufactured at the Minsk Tractor Plant. The manufacturer has simplified the design of the device as much as possible to ensure high wear resistance of the mechanisms and ease of maintenance. The device consists of three main components:

• a housing equipped with a valve block;
• special swing unit of the device;
• distribution mechanism.

The swing unit of the device consists of several parts. It is represented by a stationary stator and rotor, to which the spool of the device extends. The spool, in turn, is fixed by two springs and connected to the steering column shaft. When the steering column moves, the spool also moves and, moving relative to the central axis, supplies oil inside the device.

The special valve block inside the housing includes anti-vacuum, safety, check and shock valves. Check valves systems are necessary in case of hydraulic motor failure. In this case, the valve closes the drain channel of the hydraulic booster system, preventing fluid circulation. Safety valves regulate the pressure inside the oil piping system.

Anti-vacuum valves are responsible for transporting oil inside the hydraulic cylinders in case of an emergency in the system. Shockproof ones regulate the pressure inside the lines under excessive load in case of work on uneven sections of the road.

A dosing pump is installed on equipment whose speed does not exceed 50 km/h. It is located in the volumetric hydraulic drive of the machine.

When acting on the control system, the metering pump supplies working fluid to the hydraulic cylinders, thereby enhancing the operator’s actions. If there is no impact on the control system, the pump is in neutral mode and passes liquid directly to the drain system.

2 How to properly install the dispenser on the MTZ 82?

Installation of a metering pump on MTZ 80 and MTZ 82 involves partial replacement power steering systems (hydraulic steering) to the HSU (hydraulic steering) mechanism. The MOUNTAIN kit includes:

• special hydraulic cylinder bracket;
• reinforced steering rod;
• two levers;
• hydraulic cylinders for the front axle with a set of pins;
• dosing pump;
• high pressure channels;
• special adapter for the pump.

If necessary, a differential locking valve for the HPS mechanism is also purchased. It is used to replace the lock that is used on the power steering. Such a crane allows you to block the gearbox on unstable sections of the road, which increases the maneuverability of the equipment.

The dosing device is installed on the machine according to the following algorithm:

1. First of all, you need to remove the power steering system box (also called the distributor). To do this, the control levers are removed. Then the anther plates, anthers and seals are removed. Next, the covers are removed and the spools are pulled out.
2. The next stage is to replace the system bearings with new ones in case of wear of the already installed ones.
3. The worm of the device is removed.
4. The dispenser shaft is installed in place of the worm.
5. We screw the dosing device to the corresponding die. Installation is carried out using countersunk bolts.
6. Next comes checking the pump and after that its installation in the hydraulic booster system.

Replacement of the remaining HPS kit is carried out before installing the pump.

2.1 Do-it-yourself installation of a metering pump on MTZ (video)

2.2 Malfunctions of the MTZ dispenser pump and their symptoms

Any malfunction of the metering device or the volumetric steering system leads to complications in the operation of the control system. To restore the functionality of the system, you should clearly know which node has failed. There are a number of signs for this:

1. The front axle has become more unstable. This symptom in most cases indicates a displacement of the axis of the rotary shaft. It is also possible for gaps to form in the steering linkage or pump components.
2. Turning the steering wheel has become more difficult and requires additional effort. The cause is insufficient oil inside the dispenser. Second option - large number air inside the hydraulic system and, as a result, partially idle operation of the device.
3. Willful change in the position of the steering wheel. Self-turning of the steering wheel is a consequence of the incorrect position of the spool inside the pump. Two tension springs are responsible for its neutral position. If one of them breaks down, oil is constantly supplied to one of the cylinders, and the steering wheel turns accordingly.
4. Weak support during turning or its complete absence. This phenomenon occurs when there is not enough oil in the dispenser. Accordingly, its functionality decreases. The second cause of the problem may be abrasion of the sealing gaskets on the cylinders responsible for turning the machine.
5. When you turn the steering wheel, the tractor wheels turn in the opposite direction. In this case, the problem is that the leads to the machine's hydraulic cylinders are not connected correctly to the metering pump. As a result, the spool supplies oil to the wrong cylinder, and accordingly the wrong side is strengthened.

Also one of the problems in the work pumping equipment the power steering circuit is contaminated. When the valves of the device become clogged with dirt and other particles, they are unable to pass fluid through the system and regulate pressure. As a result, the functionality of the system is reduced and its breakdown is possible.

2.3 Device maintenance

Since the pump is not completely protected from dirt entering the system, it may become clogged. As a result, it must be washed periodically to prevent serious damage.

This event takes place after complete disassembly devices. The pump must be washed with kerosene or a liquid with similar properties. Before you start washing, you must remove the rubber sealing rings from all parts. This will prevent them from being damaged. Each part is washed individually and very carefully. Special attention should be given to the two bushings of the device. They are equipped with a series of small holes that get clogged quickly.

After all the parts are washed, the device is assembled in the reverse order. Here important point is correct installation gerotor pair and distributor leaf spring. The first part should be installed with the pump facing the holes away from you. The pair is installed in such a way that two teeth are located on a line in front of the master.