Moment tightening connecting rod nuts. Moments of threads of threaded connections. Slip bearings, their types and role in the work of the engine

ENGINE

CLUTCH

TRANSMISSION

FRONT SUSPENSION

REAR SUSPENSION

STEERING

BRAKE SYSTEM

For products from carbon steel, strength class - 2 on the bolt head, numbers are indicated via the point. Example: 3.6, 4.6, 8.8, 10.9, and others.

The first figure denotes the 1/100 nominal value of the tensile strength, measured in MPa. For example, if the marking is on the head of the bolt 10.9 The first number 10 denotes 10 x 100 \u003d 1000 MPa.

The second digit is the ratio of the flow limit to the strength limit multiplied by 10. In the above example, 9 is the yield strength / 10 x 10. Hence the yield strength \u003d 9 x 10 x 10 \u003d 900 MPa.

The yield strength is the maximum bolt workload!

Marking steel - A2 or A4 is applied for stainless steel products - and the strength of 50, 60, 70, 80, for example: A2-50, A4-80.

The number in this marking means - 1/10 correspondence to the strength of carbon steel.

Translation of units of measurement: 1 Pa \u003d 1H / m2; 1 MPa \u003d 1 H / mm2 \u003d 10 kgf / cm2.
Tightening limits for bolts (nuts).

Rough moments for tightening bolts (nuts).

The table below shows twisting moments for tightening bolts and nuts. Do not exceed these values.

The above listed values \u200b\u200bare given for standard bolts and nuts having
metric thread. For non-standard and special fasteners, see Repair Manual Repaired Technology.

Tightening torques of standard fasteners with an inch thread of the US standard.

The following tables provide general standards.
moments of tightening for bolts and SAE nuts class 5 and higher.

1 Newton meter (NM) is approximately 0.1 kgm.

ISO - International Standards Organization

Tightening torques of standard tape clamps with worm clamp for hoses

The table below gives the torque
clamps when they are initial installation on a new hose, and
also when re-installing or pulling up the clamps
on hoses, used

Tightening torque for new hoses when installing

Table of torque of typical threaded connections

The engine repair is considered in the car the most difficult, because no other item contains such a huge number of elements interrelated. On the one hand, it is very convenient, because in case of breakdowns one of them, there is no need to change the entire knot, it is enough to simply replace the outstanding item, on the other - the more component elements, the more difficult the device and the more difficult it is to deal with the one who Not very experienced in auto repair affairs. However, with a big desire, everything is possible, especially if your zeal is supported by theoretical knowledge, for example, in determining the moment of tightening the indigenous and connecting rods. If so far this phrase for you is a set of incomprehensible words, before climbing into the engine, be sure to read this article.

Indigenous and connecting rod liners are two varieties of sliding bearings. They produced according to one technology and differ from each other only inner diameter (in the rods of rods, this diameter is less).

The main task of the inserts is the transformation of translational movements (up-down) into rotational and ensuring the smooth operation of the crankshaft so that he does not wear ahead of time. It is for these purposes that the liners are installed under a strictly defined gap, which supports strictly specified oil pressure.

If this clearance increases, the pressure of the engine oil in it becomes less, and therefore the neck of the gas distribution mechanism, the crankshaft, etc. of important nodes wears much faster. Is it worth saying that too strong pressure (reduced clearance) also does not carry anything positive, as it creates additional obstacles in the work of the crankshaft, he can start twisted. That is why it is so important to control this gap, which is impossible without using the dynamometric key in the repair work, the knowledge of the necessary parameters, which are written by the manufacturer in engine repair literature, as well as compliance with the moment of tightening of indigenous and connecting rod liners. By the way, the effort (moment) of the tightening of bolts of connecting rod caps and indigenous liners is different.

Please note that the standards cited are relevant only when applying new sets of parts, as the assembly / disassembly of the former node at the expense of it cannot guarantee compliance with the necessary gaps. Alternatively, in this situation, when tightening the bolts, you can focus on the upper limit of the recommended point, or you can use special repair of liners with four different sizes, differing from each other by 0.25 mm, provided the crankshaft grinding until the minimum clearance between Drinking elements will not be 0.025 / 0.05 / 0.075 / 0.1 / 0.125 (depending on the existing gap and the repairs used).

Examples of concrete moments of tightening bolts of connecting joint and indigenous liners for some cars of the VAZ family.

Video.

The internal combustion engine constructively has a large number of conjugate parts, which are experiencing significant loads during operation. For this reason, the assembly of the motor is a responsible and challenging operation, for the successful implementation of which the technological process should be observed. The functionality of the entire power unit directly depends on the reliability of fixation and accuracy of adjacent elements. For this reason, an important point is the exact implementation of the calculated conjugations between the flushing surfaces or friction pairs. In the first case, we are talking about fastening the head of the cylinder block to the cylinder block, since the bolts must be pulled out with strictly defined force and in a clearly indicated sequence.

As for loaded rubbing pairs, increased requirements are put forward to fixing connecting rod and native sliding bearings (indigenous and connecting rod liners). After repairing the engine during the subsequent assembly of the power unit, it is very important to comply with the correct torque of the indigenous and connecting rod engines. In this article we will look at why it is necessary to tighten the liners with strictly defined efforts, as well as answer the question of which moment of tightening of indigenous and connecting rod liners.

Read in this article

What are the sliding bearings

For a better understanding of why the inserts in the engine must be tightened with a certain point, let's take a look at the function and assign the specified elements. Let's start with the fact that the specified sliding bearings interact with one of the most important details of any DVS -. If briefly, the reciprocating movement in the cylinder is converted into a rotational motion precisely thanks to the crankshaft. As a result, a torque appears, which is eventually transmitted to the wheels of the car.

The crankshaft rotates constantly, has a complex shape, experiencing significant loads and is an expensive detail. To maximize the service life of the element in the design, connecting rod and indigenous liners are used. Taking into account the fact that the crankshaft rotates, as well as a number of other features, such conditions that minimize wear are created for this part.

In other words, engineers refused to solve conventional ball bearings or roller bearings in this case, replacing them to indigenous and connecting rolled sliding bearings. Indigenous bearings are used for the crankshaft root necks. Schedule liners are installed at the tent of the crankshaft crankshaft. Often the indigenous and connecting rod bearings are made according to the same principle and differ only in the inner diameter.

For the manufacture of liners, softer materials are used compared to those from which the crankshaft itself is made. Also, the liners are additionally covered with an anti-friction layer. In place where the liner is conjugate with the crankshaft, lubricant is supplied under pressure (engine oil). Specified pressure provides oil pump. It is especially important that between the crankshaft and the sliding bearing was the necessary gap. The quality of the lubrication of the rubbing pair will depend on the size of the gap, as well as the engine oil pressure indicator in the engine lubricant system. If the gap is increased, then the lubricant pressure is reduced. As a result, rapid wear of the crankshaft neck occurs, and other loaded nodes in the DVS device suffer. In parallel with this, a knock appears in the engine.

We add that the low oil pressure indicator (in the absence of other reasons) is a sign that it is necessary to grind the crankshaft, and the engine's liners themselves must be changed based on the repair size. For repair liners there is an increase in the thickness by a value of 0.25 mm. As a rule, repair sizes 4. This means that the diameter of the repair liner in the latter size will be 1 mm. less compared to standard.

Slip bearings themselves consist of two half, in which special locks are made for the correct installation. The main task is that the clearance is formed between the neck and the liner, which is recommended by the engine manufacturer.

As a rule, a micrometer is used for measuring the neck, the inner diameter of the connecting rod liners is washed with a chute meter after assembly on the connecting rod. Also for measurements you can use control stripes of paper, uses copper foil or control plastic wire. The gap at the minimum marker for rubbing pairs should be 0. 025 mm. The increase in the gap to the indicator 0.08 mm is a reason to crowded the crankshaft before the next repair size

Note that in some cases the liners simply change to new crankshaft necks without boring. In other words, it is possible to do only to the replacement of the liners and get the desired gap without grinding. Please note, experienced professionals do not recommend this type of repair. The fact is that the resource of parts at the pairing place is greatly reduced even when we take into account that the gap in a rubbing pair corresponds to the norm. The cause is the microdefects, which still remain on the surface of the shaft neck in case of abandonment of grinding.

How to tighten the root liners and liners rods

So, taking into account the foregoing it becomes clear that the moment of tightening of the indigenous and connecting rod liners is extremely important. We now move on to the assembly process itself.

1. First of all, indigenous liners are installed in the bedside bed. It must be borne in mind that the average liner is different from others. A preservative lubricant is removed before installing bearings, after which a few engine oil is applied to the surface. After that, the lids of bed are put, after which the tightening is carried out. The tightening torque should be the one recommended for a specific model of the power unit. For example, for motors on the VAZ 2108 models, this indicator may be from 68 to 84 N · m.
2. Next, the installation of rollers inserts. During the assembly, it is necessary to accurately set the lids to the place. Specified covers are marked, that is, their arbitrary installation is not allowed. The torque of connecting rod liners is slightly less compared to the root (the indicator is within 43 to 53 N · m). For Lada Priora, the indigenous liners are tightened with a force 68.31-84.38, and connecting connecting rod bearings 43.3-53.5.

It should be added separately that the specified tightening torque involves the use of new parts. If we are talking about the assembly, in which used parts are used, then the presence of production or other possible defects can lead to a deviation from the recommended norm. In this case, when tightening the bolts can be repeated from the top plank of the recommended point, which is specified in the technical guide.

Let's summarize

Although the moment of tightening the caps of indigenous and connecting rod bearings is an important parameter, quite often in the general technical manual for the operation of a specific TC, the value of the moment is not specified. For this reason, it is necessary to separately search for the necessary data in the work of the repair and maintenance of one or another type of engine. It must be done before installing, which will allow repair work correctly, as well as avoid possible consequences.

It is also important to remember that in the event of non-compliance with the recommended effort during tightening, the problem may occur both in case of insufficient moment and when tugging bolts. An increase in the gap leads to a low pressure of oil, stacks and wear. The reduced clearance will mean that in the pairing area, for example, there is a strong pressure insert on the neck, which interferes with the operation of the crankshaft and can cause it to subdinction.

For this reason, the tightening is performed using a dynamometric key and taking into account exact effort. You should not forget that the moment of tightening the bolts of connecting rod caps and the indigenous liners is somewhat different.

Read also

Why rotates crankshaft liners: the main causes. What to do if I touched the connecting roddlewill, how to change the liners of the rods.

Without a dynamometric key in the repair of the engine there is nothing to do! Tightening torque when repairing Honda Civic is very important. Honda engineers were calculated for each bolt and nut in the car. You do not need to tighten from your hand to a characteristic crunch. First, you can break some kind of bolt, and it will be extremely difficult to get it. In the second, the Potrested GBC will clearly pass oil and coolant. In Honda Civic, like any other machine, various tightening moments are used, from 10 nm to 182nm and even more, the crankshaft pulley bolt. I advise you to purchase a powerful dynamometric key, powerful and good, with click to achieve the momentDo not take the arrow. And the last, all connections that are in the composition of one element (disk, cylinder head, covers) are delayed in several stages from the center of the outside and Zigzag. So in order, I describe everything in Nm (NM). Do not forget to lubricate the carving with oil or copper lubrication.

These moments are suitable for the entire D series D14, D15, D16. Did not check the D17 and D15 7 generation.

Moments Tightening GBC Bolts

On earlier versions, there were only two stages, later 4. Important It is desirable to stretch the bolts and in general to work with threaded compounds at a temperature not lower than 20 degrees of heat. Do not forget that you need to clean the threaded connections from any liquid and dirt. So, preferably after each step wait 20 minutes to remove the "voltage" of the metal.
P.S. Different sources give different numbers, for example 64, 65, 66 nm. Even in original directories for different regions, I am writing a medium or most familiar.

• D14A3, D14A4, D14Z1, D14Z2, D14A7 - 20 nm, 49 nm, 67 nm. Control 67.
• D15Z1 - 30 nm, 76 nm checklist 76
• D15Z4, D15Z5, D15Z6, D15Z7, D15B (3STAGE) - 20 nm, 49 nm, 67 nm. Control 67.
• D16y7, d16y5, d16y8, d16b6 - 20 nm, 49 nm, 67 nm. Control 67.
• D16Z6 - 30 nm, 76 nm checklist 76

• Locknience setting of valve gaps D16Y5, D16Y8 - 20
• Locknience setting valve gaps D16Y7 - 18
• Banjo Fuel Hose Bolt D16Y5, D16Y8 - 33
• Banjo Fuel Hose Bolt D16Y7 - 37

Other tightening moments

• Nuts on disks 4x100 - 104 nm
• Spark plugs 25.
• Hub nut - 181 nm

Find out something new

This article is relevant for Honda car release 1992-2000, such as Civic EJ9, Civic EK3, Civic EK2, Civic EK4 (partially). Information will be relevant for Honda Integra owners in DB6, DC1 bodies, with ZC, D15B, D16A motors.