Windshield wipers as an addition to the car have been used almost since the release of the first production models of the vehicle. The need to protect the windshield is due to safety measures while driving - "wipers" clean its surface, creating conditions for optimal visibility. Performing this operation requires a special technical device from the working elements, which reinforces the wiper motor and the drive system as a whole. Despite the relatively modest dimensions, this is a rather complex system, which leads to malfunctions during operation and the need to replace some elements of the mechanism.
Design and elements of the wiper
The windshield washer includes a fixing assembly, a brush and a pressure block. The fastening mechanism is removable and contains a pin and leash clamps. The adapter functions as a connector. By the way, on how well it provides connection,depends on the stability of the purifier. The pressure block directly carries out the movement of the working elements - this is a system of several plastic or metal arcs. A brush is attached to the edges of the arcs, which directly contacts the glass surface and cleans it from dirt with rainwater. The operation of the described design is provided by the wiper motor, which is controlled from the passenger compartment by means of a special handle.
The electric motor in the "wipers" is also called a gearmotor, and in modern versions it is usually a three-brush. The motor can have several speeds, while its working forces are generated by permanent magnets. The composition of this unit can be represented as follows:
- case (for the gearbox and the motor itself);
- anchor, as well as the rear and front bushings of its shaft;
- output shaft;
- driven gear;
- traverse with holders for brushes;
- felt ring;
- permanent magnet;
- idler gear mechanism.
In some versions, the wiper motor also includes protection systems - in this capacity, thermal bimetallic fuses, overload protection mechanisms are used, and chokes with capacitors also reduce radio interference.
Rear and front washers
In the process of driving, the car owner must have an overview from different angles and sides. That's whyin addition to the traditional front wiper, there are also rear versions. In the first case, a double design is provided, that is, in order to increase the cleaning efficiency, the brush has two rubber bands. Less stress is taken by the rear wiper motor as it powers the single design. However, this does not mean that the rear models have a lower risk of failure - the frequency of failures is similar to the front.
In addition, there are "wipers" for side mirrors, but due to the complexity of the implementation of such systems, such solutions are gradually becoming a thing of the past, leaving the visibility functions to the classic versions of the washers.
The wiper motor can be damaged by various factors that lead to a violation in the connections between the brushes and the collector, a wedge in the gearbox, unstable operation of the motor, etc. At the same time, the wiper motor does not always require replacement, leaving the possibility of saving operating condition by correcting the position of the system components - this applies, for example, to a bimetallic fuse. Breakdowns in resistors or switches usually lead to violations in the operation of high-speed modes.
Problems with the brushes are also eliminated by simple manipulations with the stop mechanism - in most cases, their adjustment allows you to restore the cleaning elements. Aesthetic problems, such as creaking, grinding and other unpleasant sounds, are almost always solved by cleaning the brushes themselves.In addition, the dryness of the glass also leads to the unfortunate noise.
How to remove the motor?
The main problems with the operation of the wiper still affect the elements of the motor, requiring its repair or replacement. In general, when starting any restoration operations, you should know how to remove the wiper motor without damaging its design and associated components.
First you need to unscrew the fasteners that fix the levers - this will allow you to remove the brushes from the drive splines. First of all, the nuts are unscrewed, and then the plastic bushings and gaskets are removed. Next, you need to remove the block with wires. To do this, lift the seals at the edges and dismantle through the slot in the engine niche. At this stage, the entire wiper structure should also be removed, the washer, spring and traction elements should be removed. This is an example of how you can remove the front wiper motor without interfering with the drive systems of the car itself. When the device is removed, you can begin to inspect it and identify defects. After evaluating the condition of the washer, it is necessary to make a decision - to replace it or repair it.
Features of removing the motor on the VAZ
If work is being done on one of the VAZ models, then you will have to take into account some of the nuances of dismantling. In general, the operation is similar to similar actions on other cars, but there are still some differences.
So, first, the power plug is disconnected. This element is disconnected as a result of its careful movement away from the place of fixation. Next, lift the seal, capturing its edges. Sothe hood rubber lifts up. The wires with the plug are removed through the slots, after which the motor mounting bolts are unscrewed. To finally prepare the VAZ wiper motor for dismantling, it is also necessary to lift the protection cover. Then you need to lightly press on the slotted pins - this should be done until they fall inward. This completes the procedure. The motor is ready to be removed.
How to remove the rear wiper motor?
The device and principles of fastening the rear window are somewhat different from the front, as well as the means of providing drive systems. Therefore, the approach to removing the washer with its electric motor has a number of features. Work begins with the installation of the "wiper" in a vertical position, which will make it possible to unscrew the mounting screws. Then, in order to remove the rear wiper motor, it is necessary to disconnect all external components of the system and the structure itself. In particular, the lever is removed, the protective cap on the roller, the bracket bolt is unscrewed.
A feature of this procedure is the need to remove the upholstery of the luggage compartment. To do this, you need to take out the caps in turn, blocking the approach to the wiring block. It is important to consider that you will have to remove two pads - one for harnesses, and the other for cables. When these elements are removed, you can begin to unscrew the screws that fix the motor. Then it remains to remove the drive component by turning it around.
After the outer fasteners, due towhich the electric motor is fixed will be unscrewed, you can start disassembling. In this case, it is important not to touch the adjusting bolt, since a violation of the axial clearance in the anchor shaft is possible. However, if you plan to replace the wiper motor, then this factor does not matter.
First you need to remove the panel on the gearbox, and then - its gear and mounting bolt with cage nuts. The housing is dismantled together with the brush holder and the anchor is immediately removed. It is recommended to blow out the housing with compressed air using a compressor on site. Locking rings are located on the rollers of the mechanism - they should be removed completely together with the adjusting washers. Pull rods and o-rings out of the bracket. The latter should be removed from both sides of the bracket - from the grooves.
Technical restoration of an electric motor may concern its different parts, as well as the condition of contacts and boards. In some cases, only cleaning of the elements is also allowed, while other problems require their complete replacement. As a rule, repair of the wiper motor is carried out after a thorough check of the condition of the following parts:
- springs on motor brushes - poor quality of movement leads to the need for replacement;
- collector - usually cleaned with abrasives (if the element is burned, then the anchor must be replaced);
- gear in the gearbox needs to be replaced if broken or worn teeth are detected;
- wiper rods are replaced if theycurved;
- all rubber elements in the presence of the slightest cracks, breaks and scratches must also be replaced;
- contacts may be burnt or oxidized (in such cases, they are cleaned with fine-grained abrasive).
Of course, there are often cases when the repair of the wiper motor with the replacement of all the listed elements does not give the expected result. This usually happens due to the incompatibility of the device with the characteristics of the car itself or due to serious damage to the board, for example, if there is a burning of contacts with wires. Also, the inevitability of a complete replacement of the device arises if the entire filling of the motor requires a comprehensive repair. While recovery is theoretically possible, the result is unlikely to ensure long-term operation of the wipers.
Assembly and installation of the motor
If you decide to purchase a new wiper motor and install it on the old design, then you can proceed in the reverse order during installation. In this case, it is desirable to mark the adjusting elements even at the disassembly stage. This will allow you to determine on the spot how to replace the wiper motor by installing a working analogue in the same place and with the same settings. This rule also applies if the old electric motor was repaired - it is assembled and installed in the reverse order, but it should be borne in mind that when mounting the armature in a special shaft connector, a thrust ball must be built into the housing.
In the process of assembling the gearboxit is advisable to lubricate its gear and shaft worm. Grease solutions can be used as a lubricant. The same applies to the procedure for installing the thrust in the bracket - in this case, the rollers are lubricated. The crank mechanism is installed parallel to the shortened rod with the direction towards the electric motor.
Checking the performance of mechanisms
At the repair stage or during the preventive check of the windshield wipers, problems in the device can be detected in several ways. The quality of the mechanism is primarily indicated by the function of the brush and its position in the brush holder. The cleaning elements must move freely and easily in accordance with the set speed. The electric motor itself is checked by a tester. In particular, such diagnostics makes it possible to detect violations in contacts and connections. In disassembled form, the device also allows you to evaluate the condition of the gear of the gearbox - in particular, the mentioned teeth and threads on the rollers are checked. The remaining components can be checked with the naked eye even with a superficial inspection.