Crankshaft inserts: purpose, types, features of checking and replacing

The engine is a complex multi-component mechanism, each part of which ensures correct and balanced operation of the entire system. In this case, some play an important role, while others do not have this value. The crankshaft, as well as all the elements related to it, is the most significant part of the engine. It ensures the rotation of the wheels by transferring the energy of the burning gasoline. Crankshaft inserts are small-sized pieces in the form of half rings, made of medium-hardness metal and coated with a special anti-friction compound. In the process of long-term operation of the car, they are subject to severe wear and tear, which makes it necessary to purchase and install new parts.

Description

Crankshaft inserts act as sliding bearings to ensure crankshaft rotation. This process occurs as a result of combustion of fuel in the chambers of the cylinders. Active friction of parts caused by increased loads and high speed mode, is able to disable the motor. To prevent this situation and reduce the degree of friction, all the components that have the highest value are covered with the finest micron layer of oil. This function is assigned to the lubrication system of the motor, while the film on the existing parts is formed only under the condition of high oil pressure. The lubricant layer also covers the contact surfaces of the crankshaft inserts and neck. In this way , the frictional force generated is substantially reduced .

Types and sizes

ВАЗши коленвала ВАЗ act as protective elements preventing premature wear of the mated parts. Depending on their location, they are divided into two varieties: indigenous and rod-shaped. The latter, as was indicated earlier, are located on the neck of the shaft, the indigenous ones are on the crankshaft at the place of its passage through the ICE and have a similar purpose. Different types of power devices require the use of appropriate elements, first of all, the inner diametrical size should be selected.

Repair parts are different from each other, and have significant differences in comparison with the new elements that are equipped in the factories of new cars. The parameters differ by at least a quarter of a millimeter, all subsequent versions go through a similar step.

Appointment

The crankshaft is constantly subjected to high physical and temperature stresses during operation, the conrod bearing shells keep it on the axle, while the function of the crank-connecting rod is maintained only by the elements indicated above. The mechanism of the action of the necks is represented by inner cages, as a consequence, the crankshaft inserts are external. The lubricant is fed to them through a special oil supply network in which the liquid moves under high pressure. So the very thin film is so necessary for the crankshaft.

Causes of breakage

Constructive damage and wear during use are the most common reasons for replacing parts. Despite the regular supply of grease and the accurate operation of the motor, this process is inevitable. With the passage of time, the surface of the necks is thinned, the free space between them becomes larger, because of this the crankshaft acquires a free stroke, the oil pressure decreases and, as a consequence, feeds it. All this causes premature failure of the entire engine system.

Scrolling is the second reason for repair work. Many people have heard about this or deal with the problem on their own, but not all car owners know what makes this situation. The connecting rod inserts have thin plates that lie in a special bed. In this case, small projections are located on the entire outer surface of the semirings, they must touch the front of the block, as is the case with new motors. Some conditions reduce the resistance of the antennae in relation to the liner, it sticks to the neck of the crankshaft and turns. In this situation, the engine stops working. It is worth noting the most frequent reasons for its development:

• The functioning of the motor is associated with a constant excess of the established loads;
• The lubricant is too liquid;
• Bearing caps stand with low interference;
• Absence of oil, its excessive viscosity or presence in the composition of abrasive compounds.

Preliminary work

If it becomes clear that repair of the power device can not be avoided, it is necessary to reveal the degree of wear of all the elements and determine the required dimensions of the crankshaft inserts. Most motorists solve the problem of picking up the dimensions by visual inspection, for more accuracy you can use a micrometer. Also it is worth paying attention to the possibility of boring. When there is a scrolling of the elements, they must be replaced immediately with new ones. Before starting the repair, it can be determined by the operation of the engine, in particular it can often stall, or by the specific sounds of the crankshaft. If the necks are jammed, further movement becomes impossible.

Regardless of the situation, all the details of the mechanisms should be carefully inspected. On the necks there may be damages of a wavy appearance, which are easy to feel with hands, in this case it is necessary to conduct a boring and put repair parts, the dimensions of which correspond to the installation site. Due to the large amount of damage, a more intensive boring may be required, and as a result, details of a size quite different from the previous ones will be required. Therefore, the connecting rod crankshaft is purchased after all the procedures, so you can avoid the need to return the item to the store.

Algorithm of installation actions

The most common method of solving the problem among many people is to contact the car service center. But the replacement of crankshaft inserts is possible for any person who has at least the slightest experience in repairing and possessing a certain set of tools. To simplify the task it is necessary to follow a certain order of actions.

First, check the clearance between the liner and the crankshaft. The check is made using a calibrated plastic wire, which can be found on the necks you need. Then the cover is mounted with the liner, they are tightened with a certain force corresponding to a value of 51 Nm. It is worth using a torque wrench to measure. After removing the lid, the gap will be the same as the degree of compression of the wire. With the help of a nominal gap, it is necessary to evaluate the resulting parameter, the value of which for each individual brand is different. If it becomes clear that the gap exceeds the nominal value, that is, the degree of squeezing, then you can not do without installing repair parts.

Boring

All the connecting rods are removed after a consistent check of the gaps, the crankshaft is also dismantled and ground. Boring is possible only on special equipment - centripetal, which is rarely found in ordinary car owners. Therefore, you will need to contact specialists. After grinding, the crankshaft inserts of the appropriate size are selected. Here you can not do without such a tool as a micrometer, and fitting the selected elements. Then all the crankshaft parts are installed in the reverse order and the caps on the main bearings are screwed.

It is worth noting some features of the reverse installation of connecting rods and liners. The latter are pre-lubricated with oil, and the lids must also be screwed. Compared with the ongoing preparatory work, installation takes much less time. In this case, do not forget about the operation of the crankshaft, which is characterized by high loads, as well as its high cost. It is necessary to do everything possible to increase the period of functioning. The main role here is played by grinding, carried out at an appropriate time. This procedure ensures the smoothness of the necks and prepares them for further operation.

What you need to know

Despite the complexity and multicomponence of such a part of the car as a motor, many people easily dismantle it for work. But when installing liners, it is worth paying special attention, because excessive tension or, conversely, insufficient force can cause a secondary cranking of the elements. In the absence of confidence in their own abilities and knowledge, it is worth turning to qualified specialists.

How to choose

Regardless of the cause that caused the engine repair and the replacement of the liners, boring the crankshaft is a must. Installation of new parts is only possible on the ground or new mechanism. In the presence of damages and ruts on only one neck, all elements are processed to achieve a single common size. Standard parts are installed in the process of assembly of the engine. For example, crankshaft repair inserts for VAZ cars are implemented in four versions. That is, a boring can be made up to a maximum of four times. Motors for such machines as "Moskvich" and GAZ, have an additional fifth and sixth polishing to 1.5 and 1.2 mm respectively. The best option would be to select the required dimensions by the person who was polishing. Boring can lead to the need for selection of elements, the size of which significantly exceeds the previous one. This depends on the depth of the ruts on the necks and their number. Inserts are on sale in the form of kits for both types of necks.

Features of the work

Replacing the crankshaft inserts requires compliance with the following rules:

• On the crankpins there are special dirt traps, they must be cleaned during the work;
• Protrusions located at the junctions and ensuring the fixation of the liners, must enter freely into the grooves (the efforts of the hands should be quite sufficient);
• The replacement is done without adjusting actions;
• Work with the root parts are carried out on the previously removed motor, while installing the connecting rod it is not necessary to remove it;
• At the end of all actions the engine must be run-in.

Alternative replacement crankshaft inserts

Without removing the engine, you can also replace the crankshaft inserts, the only thing is to take into account some of the difficulties. To ensure easy access, the crankshaft must be at least 1 cm below the standard level. It is necessary to do this without removing the box or partially unscrewing it and moving it in the opposite direction from the motor. Also, all belts must be removed. To install the last insert it is often necessary to lower the shaft even lower.

Marking of liners

If you need to select the details of standard parameters, you should start from the color code, which can be found on the elements that are being replaced. If these designations are not available on them due to considerable wear and tear, it is worthwhile looking for the marking on the connecting rods, more precisely on their lower heads. Also it is necessary to check the conformity of marks on the shaft itself, they determine the parameters of the necks being installed.