How to Disassemble a Reducer Angle Grinder Makita 9069

The famous Japanese brand Makita enjoys well-deserved popularity among consumers around the world. All Makita brand products are distinguished by high quality, ergonomics, reasonable prices. A competent Russian consumer is trying to squeeze out of the tool more than he can give. Angle grinders Makita have their ultimate strength.

Do-it-yourself Makita angle grinder repair is not particularly difficult and can be performed both in the service center and independently, since you can freely purchase the necessary parts. Faults angle grinder and methods for their elimination are discussed in detail in the attached instructions.

Design Features Makita Angle Grinder

An angle grinder is an angle grinder that received such a name only in the vast expanses of the former USSR. Structurally, any angle grinder (angle grinder) is designed identically.

The principle of operation of Makita grinders is based on the conversion of electrical energy into mechanical energy. This leads to the rotation of the shaft on which the disk is mounted for cutting, grinding, polishing. And it is called angular for the reason that in the gearbox used, the torque is transmitted at an angle of 90º.

Since the cooling of the electric motor in the Makita angle grinders is ensured by the intake of external air through the ventilation holes, the working parts of Makita grinders are coated with a special protective powder varnish that prevents dust from settling. Structurally, a Makita angle grinder provides a labyrinth system of seals and the Start button is sealed.

But each company introduces its own zest into the design to attract customers. Not deprived of this and the Makita angle grinder. Makita angle grinder is conditionally divided into powerful and small.

Makita angle grinders are marked depending on the power of the electric motor.

The design features of Makita angle grinders include:

  • The presence of a labyrinth device that protects the bearings from dirt and dust.
  • The motor windings in high power angle grinders are protected by an armored coating.
  • Makita angle grinders are equipped with a special system that protects the tool from jerking during startup, called the Super-Joint-System.

A few words about the SJS system. The system prevents the impact of a reverse impact, eliminates jerking and jamming of the working body, protects the motor from overloads.

How to Disassemble a Reducer Angle Grinder Makita 9069

The system uses a spring, the purpose of which is to transfer forces from the rotor to the gears of the gearbox. The spring acts as a buffer, prevents jerking when starting and stopping. This design significantly reduces vibration and ensures smooth operation of the Makita angle grinder

Makita angle grinder is divided into classes according to the size of the width of the working disk. The angle grinder is conventionally divided into three classes: light, medium, heavy. In turn, each class is divided into an angle grinder for professionals and for domestic needs. Professional models of Makita grinders have an increased power reserve, an integrated security system, and an increased working resource. Professional angle grinders withstand high loads for a long time.

Makita household angle grinders have high performance, but very affordable prices. For Makita grinders, a disc with a maximum diameter of 230 mm can be used.

Depending on the diameter of the disk, Makita ears are divided into classes:

  • Diameter 115-125 mm characterizes the lightweight class. Easy to hold with one hand on the body, which acts as a handle. But professional angle grinders of this class can be equipped with a rear handle, which has a built-in power button;
  • The diameter of 150-180 mm relates the Makita angle grinder to the middle class. This category includes professional and amateur models equipped with electric motors of various powers. Modern models have a rotatable rear handle;
  • A diameter of 230 mm characterizes a heavy-class angle grinder. Makita Angle Grinder is exclusively for professionals in this class. These machines are designed for work on concrete, stones, bricks, etc. All modern consumer protection systems against injuries are incorporated in their design.

Models Makita angle grinder is available for discs with diameters of 115 mm, 125 mm, 150 mm, 180 mm and 230 m.

In high-power angle grinders, carbon brushes can be replaced without removing the stator housing cover.

Makita angle grinders of various capacities differ in appearance. Professional grinders with a power exceeding 1000 W have a large case and a convenient rear handle. The handle is equipped with protective anti-vibration pads in black. Angle grinders with power up to 1000 W have a convenient housing that acts as a handle.

A Makita quick-release casing is installed on Makita angle grinders. This design allows you to quickly remove the protective cover.

Repair tool required

Do-it-yourself repair of Makita angle grinders requires the use of a specific tool. Do not do without a set of screwdrivers. It is preferable that they be equipped with a ratchet mechanism. The best option is to use a cordless screwdriver. To repair the electrical part, a Makita angle grinder, you will need a tester, a device for determining short-circuited turns of IK-2. And also prepare an open-end wrench, bearing pullers, a hammer, a soft metal extension. Well, you can’t do without the necessary grease, cleaning materials, fluids for washing old grease.

Doing the repair of your ears with your own hands is necessary with the preparation of the workplace, the installation of proper lighting. You will need a diagram of the angle grinder of the desired model and the proposed instruction.

Any malfunctions of power tools are divided into two types: electrical and mechanical.

We will consider the repair of nodes with a Makita angle grinder using the example of a Makita 9565 worm scheme.

Possible electrical problems

Electrical faults Makita angle grinder can be divided into control circuit faults, rotor failure and stator failure.

How to troubleshoot control circuits Makita angle grinder

If your Makita angle grinder does not turn on, the biggest cause may be a breakdown in the power and control circuits.

To get to the components of the control circuits, it is necessary to remove the back cover of the case pos. 38 by unscrewing the self-tapping screw 4 × 18 pos. 39. The ST115-40 K9565 switch pos. 28 is mounted in the switch holder pos. 27. The switch holder is closed by a cover pos.29, which is mounted on the motor housing pos.33.

The power cord, item 37, is suitable for the switch. Using a tester, check the continuity from the terminal of the plug to the switch terminals. The switch pos. 28 is controlled by the lever pos. 30. From the switch contacts, check the circuit to the carbon brushes pos. 42.

In the control circuits, the weakest link is carbon brushes. In the Makita 9565 angle grinder, carbon brushes CV-318 with auto power off are used, so check the brushes.

In professional angle grinders, speed controllers are installed. In Makita angle grinders with a power of more than 1000 W, a soft start system is provided. The Makita 9077SF is equipped with such a system.

If the circuit breaker fails, the fault is eliminated by its complete replacement. In case of breakage or breakdown of the power supply wire, the fault is eliminated by replacing the whole wire or removing damaged parts.

The activation process is carried out using the lever pos.30. If you dismantled the body of the angle grinder for repair or maintenance, grease the lever slots with silicone grease before assembly.

Motor check

In addition to the control circuits, the rotor and stator are included in the electrical circuit of the angle grinder. These are complex units, the repair of which is recommended to be performed in specialized centers. But for Russian craftsmen there is nothing inaccessible. We recommend our own ways to repair the stator or rotor with our own hands.

How to repair a stator Makita angle grinder

On the failure of the stator pos.24 angle grinder indicates the appearance of burning smell, overheating of the body angle grinder, spontaneous set of revolutions angle grinder. In the case, the angle grinder pos. 33 stator is fastened with four self-cutting screws 4 × 70 pos.21. To prevent damage, the stator is closed by the protection pos.20.

Stator repair Makita angle grinder consists in determining a short circuit or open winding. It is best to perform stator diagnostics with a special device called the IR-2. The stator is considered faulty if traces of darkening of the winding are visible, an open or short circuit of the windings is detected.

The stator is easy to repair. It is necessary to rewind its windings.

How to repair a Makita angle grinder rotor

During overheating, the angle grinder, the appearance of a burning smell, and an increase in sparking in the collector area, it is necessary to pay attention to the integrity of the rotor pos.13.

Scheme Makita angle grinder

Dismantling of the rotor is associated with sequential disassembly. To remove the rotor, it must be freed from the gearbox pos.3. To do this, unscrew the hexagon nut M6 pos. 4. To unscrew the nut, hold the rotor with one hand. With your other hand, using an open-end wrench, unscrew the nut counterclockwise.

Remove the nut, pull out the flat washer pos. 5, remove the bevel gear pos. 6, remove the lock spring pos. 7. Swing the rotor to the sides, carefully pull it out of the gear housing, pos. 3. After removing the snap ring pos. 8, use a puller to pull off the bearing pos. 9.

In the Makita 9565 angle grinder, a bearing 6001LLB is used.

It remains to remove the flat washer pos.10 and gearbox cover pos.11.

Here is the rotor appearance with a Makita 9565 angle grinder with an insulated washer pos. 14, a flat washer 7 pos. 15, a bearing pos. 16 and a rubber boot 22 pos. 17. The angle grinder on the collector side uses bearing 627zz. Russian analogue 80027.

Rotor repair consists of replacing it with a new or repaired one. You can repair the rotor yourself, but you need not only patience, equipment, material. This is a kind of high-end work.

Mechanical damage

In addition to the electrical part, the mechanical part also enters the angle grinder, the main unit of which is the gearbox.

How to repair a reducer angle grinder

The gearbox consists of a housing, a drive and a driven gear. The pinion gear is mounted on the rotor shaft. The driven gear is mounted on the spindle pos. 50.

On the Makita 9565 angle grinder, the driven gear is pressed onto the spindle. And in the model, the Makita 9558HN angle grinder driven gear is mounted on the shaft using a keyway.

Gearbox malfunctions are associated with the failure of the gear teeth. Gears lick or chipped part of the teeth.

Gearbox repair Makita angle grinder is to replace a pair of helical gears. Replacing gears is done only in pairs.

To remove the driven gear can not do without a press or a special puller. Do not use a hammer, as the gear housing is made of brittle material.

Assembly angle grinder Makita 9565

Before assembling the Makita angle grinder, check the integrity of all parts and their cleanliness. Assembly begins with the installation on the spindle of the bearing and the driven gear.

Spindle assembly

On the spindle pos. 50, put on anther pos. 51, housing cover pos. 53, bearing housing pos. 54. Insert the 6201LLB pre-lubricated bearing into the bearing housing. Press in the driven gear pos. 56. On the spindle. The spindle is assembled.

Installing the rotor in the gear housing

Insert the repaired or new rotor with the bearings on into the gear case, put on, according to the drawing, all the details, put on the drive gear and fix it with a nut.

In the process of installing the rotor in the gear housing, control the mounting of the bearing. A correctly installed rotor easily rotates in the gear housing.

Installing the rotor in the stator housing

An assembled gearbox with a rotor is inserted into the stator housing, onto which the bearing from the collector side is pressed, covered with a protective rubber boot, and ease of rotation is checked. It remains to install the assembled spindle in the gear housing.

Insert the assembled spindle into the gear housing, pos. 3, after laying the rubber ring pos. 55 and lubricating the bolts pos. 52 with sealant.
Service Makita GA 5030 \ Chinim Makita 5030

All operations for assembling the mechanical part of the angle grinder are accompanied by the obligatory lubrication of the parts. Pay particular attention to the process of applying grease to the angle grinder gearbox.

It is important not only its quality, but also the quantity. Grease in the volume of 1/3 of the volume of the gearbox is placed in the gear case of the angle grinder.

Having assembled the mechanical part of the angle grinder, each time before tightening the fixing screws, check the ease of rotation of the gearbox by turning it on the spindle.

At the final stage, it remains to install the carbon brushes, put on the back cover of the case and check the operability of the tool.

In the Makita 9565 angle grinders, carbon brushes CB-325 are installed. Timely replacement of carbon brushes will not only save the rotor, but also extend the life of the entire tool.

As a rule, carbon brushes change after 7000 hours of operation or when worn down to 8 mm in length. In emergency cases, you can use homemade carbon brushes. But at the earliest opportunity it is necessary to establish relatives.

If your angle grinder after assembly works without extraneous noise, without jerking, you can be congratulated. Repair task Makita angle grinder completed.

A few words about fakes

On the Russian tool market, there are often fakes of Makita grinders. A popular and promoted brand is popular not only among users, but also of various swindlers.

Most often, powerful Makita angle grinders are faked. For example, Makita 9069.

When choosing a Makita angle grinder, pay attention to the following details:

    Quality molded plastic parts;
    workmanship of the extra pen;
    low price should alert you;
    carefully study the plate, on it you can find a lot of inaccuracies;
    Makita angle grinders must have a serial number;
    on the cases of Makita grinders the obligatory inscription is applied, which you will not find on fakes;
    on the carbon brushes of the original Makita, the regular numbers are marked;
    as a rule, hex head screws are used in the assembly; Philips screws are used on counterfeits;
    windings of the anchor and stator at fakes are covered with artisanal varnish.

Being careful when choosing a Makita angle grinder, you will not run into a fake and get a real tool from Japanese manufacturers.