How to Disassemble a Makita 2440 Hammer

Repair of the punch is difficult due to the layout of the nodes with mechanical coupling and the energy block. All parts have micron tolerances and a verified sequence of actions. Therefore, it is necessary to ensure proper maintenance and technical operation of the tool in accordance with the requirements of the instructions, thereby extending the overhaul period.
Rotary hammer device
There are few users of the tool who have studied not only the order in which levers and buttons are pressed, but who understand what is happening in the mechanism as a result of the received command. Without knowing the interaction of the nodes, it is impossible to perform even the smallest repair of the punch.
There are signs of malfunctions that relate to the power unit, and sometimes mechanical wear or breakage of parts occurs.
Power part of the percussion instrument
Electrical circuits and equipment are concentrated in one part and are presented in a section in the photo.
Symptoms that require replacement of parts or repair of a rotary hammer in the power unit may include the following:
- when the device is turned on, the mains fuses are activated;
- the device does not turn on;
- when working, smoke appears with a pungent odor;
- during operation, the apparatus sparks;
- revolutions are not regulated.
You can find the reason why the device does not turn on with the help of a tester. You need to look for a gap in the scheme, from simple to complex. Check connections, strip contacts. The most complex and expensive part that has failed is the punch anchor. This is the heart of the engine, composed of copper coils interconnected and fastened by lamellas. In the event of a breakdown of insulation between the wires at any place, a short circuit occurs, and the entire collector needs to be rewound or replaced.
It is possible to determine that the anchor on the punch is defective visually by a burnt-out winding, traces of smoke from the lamellas, or by testing for a short circuit. Damage can be eliminated by timely care and cleaning of parts from dust, which is the root cause of all troubles. If the spark comes from the engine, the anchor must be cleaned with an alcohol swab or a regular school gum to remove graphite deposits from the collector.
The second important part of the engine is carbon or graphite brushes. It is through the moving contacts that an electric charge enters the core, creating a torque induced by the EMF. Rotary hammer brushes are a contact connecting a rotating collector to an energy source.
Two elements always work in pairs. A carbon or graphite plate is pressed against the collector. As a result of constant friction on the rotating collector, the plates are abraded and the contact is broken. A sign of malfunction will be sparking in the manifold, perhaps the engine does not develop speed. Regardless of the state of wear, both plates change simultaneously. Most tool models include brush wear indicators that alert the user in advance.
The rotary speed of the punch may not be regulated due to a malfunction of the control unit, then it must be replaced, the device cannot be repaired.
Mechanical malfunctions and their elimination
To find this or that malfunction, it is necessary to reach the necessary node. Any of the sequentially removed parts is carefully inspected for:
In most models, they are disassembled into two halves, but each of the perforators has features. How to properly repair the punch yourself, watch the video:
A sign of failure can be:
- refusal to perform a function;
- extraneous sounds inside the mechanism and excessive heating of the case;
- modes do not switch;
- grease is flowing.
Each of the signs can be the result of a breakdown of any of the parts that are removed in the sequence indicated in the diagram. Assemble the tool in the reverse order. Rotary hammer parts must be purchased according to the specifications in the service manual.
One of the causes of mechanical failures is often the lack of maintenance of the unit, operating in difficult conditions. Preventive measures are not complicated, and the life of the tool will be extended significantly. According to the rules of operation, it is necessary:
Video: How to Disassemble a Makita 2440 Hammer
- renew gearbox lubricant every six months;
- after 6 months, inspect and clean the brushes, and the adjacent part of the collector;
- at the end of the working day, clean the hammer with a vacuum cleaner;
- do not forget to apply grease to the shanks of the mortising equipment to seal against dust and prevent the development of a socket.
Do not exert physical effort when working with a hammer drill, the striker and seals wear out, the operator is tired and irritated.
Goals and objectives of tool lubrication
Often the cause of a tool breakdown is a lack, defect or improper lubrication. Abrasive wear is reduced if all gaps and cavities are covered with a layer of antifreeze, and cleaning is carried out in a timely manner.
The type of gear lubricant is different from the composition for shanks. Each manufacturer recommends the use of a specific lubricant for the drill, specified in the instructions, with the desired frequency.
There are general recommendations for all rotary hammers. Gearboxes should receive a liquid consistency oil poured into a special hole. For all units, no doubt, you can use Bosh and Makita grease, designed for gearboxes, which is done in service centers.
Improperly selected or excess grease can lead to overheating of the gear unit.
To lubricate the tool shanks before inserting into the cartridge, grease of a thicker consistency is used, from the same manufacturers. In this case, the shank attachment unit in the cartridge and the striker is protected from development. Filling all gaps with grease protects the unit from dust.
Lubricate the places indicated in the instructions. And certainly, it’s harmful to add lubricant to the clutch. In the event of a sudden lack of lubrication in the gearbox, you can use the domestic composition, Litol-24 Lux, but for cordless rotary hammers, lubrication is not suitable, even temporarily.
The device of the working unit and tooling punch
The rotary hammer has a cartridge in which working tools are fixed. For professional heavy punchers, SDS max cartridges accept only shanks with a diameter of 18 mm with five longitudinal grooves, which are installed in the socket of the cartridge of the corresponding profile.
The light and medium tool is equipped with an SDS plus chuck, which allows the use of a mortising tool with four longitudinal grooves and a cross section of 10 mm. The cartridge for the punch is designed so that it can only accept the tools intended for it. If you insert the wrong equipment, it will not enter the socket, or will be installed sideways. Attempting to work will destroy the mount. But the drills do not have a shank with grooves. An add-on cartridge is used, which is installed in the SDS profile. But at the same time the tool lengthens. The drill chuck for a drill can be keyless or keyless. The adapter is used only with the SDS chuck, since the more powerful hammer drill does not have a drilling function without impact.
The puncher is a multifunctional tool. It can use modes:
- shock;
- percussion with drilling;
- drilling if there is a special chuck.
To work in shock mode, there are many devices used to facilitate manual labor.
Hammer drilling is carried out only with the use of drill bits:
- Boer;
- hollow crown;
- blade for gating.
A drill is a tool that has a shank of a special profile, a working part, which is a screw and a tip made of special steel with a centering tip. The destruction of the material occurs not by scraping, but by chipping away the rock. At the same time, a punch with a turn occurs, as a result of which the chipped pieces are removed along the screw surface of the working part.
Drills for the punch set when working in shockless mode. With this tool, a lightweight punch can work like a regular wood drill. If necessary, the device can be used to tighten the fasteners, if the reverse function is provided.
A hollow crown is needed to directly make through passages for cable wiring or to create recesses in the body of the structure for installing devices. The crown creates an annular passage, leaving a column in the middle. Since the nozzle has a special toothed profile, the metal reinforcement in concrete will render the cutters unusable.
The recesses in the wall can be made with a special trowel for gating, but the holes will not look as neat as those made with a crown.
Buchard has long been considered a sculptor’s tool. The craftsmen used forging and cross butchards. This is a percussion instrument resembling a hammer, whose striker is serrated. The sculptor was cutting off the excess with the hammering hammer, and the cross shaped the stone.
When using one shock mode use with nozzles:
- shoulder blade or flat chisel;
- peak;
- duct chisel;
- Buchard.
The punch blade is designed to level the surface of solid material. Using this equipment, you can remove tiles from the walls, remove bumps from the surface of the hardened concrete. Correction of some flaws when installing apertures in multi-storey construction is carried out using this tool. The perforator chisel used on concrete can have a different width, depending on the tasks performed. Suitable accessories for all rotary hammers. They also use specially created, narrowly targeted nozzles. a chisel, a tamper plate or a mortar cutter.
When dismantling building structures, a fracture force is required. To destroy a wall or partition, concentrated at one point, the impact of the peaks is provided by the power of a perforator.
Buchard represents a nozzle obtained by casting, a very strong sledgehammer. The teeth on the bushard are carbide, withstand large shock loads. To remove from the wall, to repel a layer of concrete, to bring down a layer of rust from a metal. this is the area of application of bouchards. If the walls are treated with this tool before plastering, reinforcement is not required. Do not use the hammer for the punch in the mode with scrolling tool. The inevitable consequence will be jamming.
Rules to be observed
During operation, the hammer quickly heats up. In order to maintain the tool’s performance for a long time, it is necessary to take a break of at least 10 minutes after 20-30 minutes of operation.
In the process, when scrolling the idle tool, you need to remove crumbs and dust, clean the punched hole to facilitate the work of the tool. When drilling holes of large cross-section, at first they are drilled with a thin drill, then with the middle one, making a hole in three steps. Long through passages need to be drilled first with short nozzles, gradually replacing them with longer ones.
After work, it is necessary to tidy the punch and used nozzles. Tools must be dust free and dry placed in a container.