You can often hear from old drivers: "Well, the water has gone into the hut!" An inexperienced motorist in surprise will begin to examine the rugs, glancing suspiciously at the area of ​​the stove, or will simply look at the speaker in bewilderment. What's the matter here? In that they say so, when the coolant got into the oil pan. The reason for this, most often, is the burning out of the cylinder head gasket (cylinder head). What it is, and how to fix such an attack at the "Priora" is written below.

Signs of burning out the cylinder head gasket

This usually occurs in the areas between the cylinders. This is the thinnest gasket spot. And the degree of damage varies. Also, signs that the gasket requires replacement depend on which of the channels in the block wall was damaged:

1. Oil.
2. Cooling systems.
3. Both at once.

If the oil channel is damaged, engine oil will start to enter the working cylinder. This will cause rapid oiling and plug failure. Misfires appear. The engine is "troit". This feature is, in general, common to all variants. Oil consumption increases.

If there is a breakdown in the cooling system, then with minimal heating of the engine, the coolant in the expansion tank comes out in bubbles. The impression is that the engine is "boiling", although the temperature is normal. There is an abundant flow of condensate from the exhaust, with a smell of coolant. Well, damage to two channels on the "Prior" leads to the ingress of liquid into the oil pan. The oil turns gray and bubbly. This is immediately visible on the oil level dipstick. Compression in the cylinders of the Priora engine also drops.

Attention! If a cylinder head gasket is found to be burned out, it must be urgently replaced. Do not shelve to avoid engine overhaul.

The Priory cylinder head gasket is made of special paronite and metal. When buying from a store for a replacement, it is worth carefully checking the part for cracks and kinks. Unfortunately, these defects are not uncommon.

How to replace

This work belongs to serious types of repairs. Therefore, you need to approach it carefully. After all, you have to remove the cylinder head on the Prior. It takes place in several stages:

1. Preparation of "Priora"
2. Electrical disconnection.
3. Removing the intake receiver.
4. Removing the timing belt (timing)
5. Removing the valve cover.
6. Removing the cylinder head directly.
7. Checking the head condition.
8. Replacing the gasket.
9. Reassemble in reverse order.

Preparation consists in checking everything necessary for this operation, keys, replacement gaskets, sealant. Removing the decorative cover from the engine. Drain coolant. Remove the throttle actuator and the air pipe. Then the battery is disconnected, and the disconnection of the connectors of the sensors and actuators begins. These are the sensor for throttle body, camshaft position, oil pressure, idle speed regulator, ignition coils and injectors.

The receiver is separated after unscrewing 2 nuts by 10 at the top and 5 nuts and bolts by 13, securing it to the cylinder head. Disconnecting and installing the timing belt is sufficiently described in many articles. Disconnect the fuel line using the 17 keys. Disconnect the cooling system pipes. Unscrew the cover bolts with an 8 socket wrench. There are exactly 15 of them. After removing the cover, unscrew 10 cylinder head bolts with a hexagon and remove it.

Important! Check the condition of the head for curvature using a metal ruler. If there is the slightest suspicion that the head has "led", give it to the turner for grinding.

Replace the gasket. Before installing a new one, apply a thin layer of special sealant to it. Reinstall and reassemble in reverse order. When replacing the gasket, special attention must be paid to the order of tightening the head bolts. The durability of the new Priora gasket, installed instead, depends on the correct tightening. You need to tighten it starting from the center, and crosswise move to the edges. In different directions. Then the gasket set to replace the burnt-out gasket will last a long time.

Many owners of Lada Priora, in the process of servicing and repairing a car, independently replace the block head gasket or lapping the valves. In the course of such work, it is important to observe the sequence and tightening torque of the cylinder head on the Prior.

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When is the block tightening necessary?

During the operation of any car, including the VAZ 2170 Priora, a long-term cyclic effect of gases in the engine cylinders is exerted on the engine head. On old power units, the tightening of the cylinder head screws could weaken from such loads and it was periodically required to bring it to a normal level. Today, bolts made of special steel are used on all VAZ Priora engines, which are tightened once for their entire service life.

When oil appears, it makes no sense to additionally tighten and stretch these bolts, since this will not improve the tightness of the joint. The only correct way to deal with a leak is to remove the head, check the evenness of the mating surfaces and replace the gasket. After performing any repair work related to removing the head from the engine, it must be tightened in compliance with all the necessary conditions.

Nuances of work

Engines with a working volume of 1.6 and 1.8 liters and a different number of valves in the heads - V8 (or 8V) and V16 (or 16V) - were installed on Lada Priora cars at different times. The type of the head of the unit determines the size of the bolts, the order of their installation and the moment on the Prior.

If the machine is equipped with an 8 valve engine, then different sized head mounting bolts can be used on it:

• on old 21114 motors, M12 * 1.25 screws with a hex head are used;
• on the more modern 21116, which went into production approximately from the middle of 2011, M10 * 1.25 elements with an asterisk head are installed.

When installing the removed head, it is necessary to use new screws, as the old ones will be stretched and have internal damage.

Also, on the motors, gaskets of different design are used - combined on the old unit and completely iron on the new one. The bolt tightening procedure is exactly the same for motors with metal and combination gaskets.

The main nuances during the performance of work are checking the length of the fasteners, observing the sequence of tightening the screws and monitoring tightening efforts. Violation of these conditions will result in damage to parts and the need for additional repair work. The procedure itself is not complicated and can be done independently in any convenient place - in a garage or in an open parking lot, with the exception of the case of mounting the head on the engine, which is desirable to be installed indoors.

It is important to remember that tightening the bolts "by eye" without a torque wrench is unacceptable, since uniform adhesion of the mating surfaces of the head and the block will not be ensured.

Tools and materials

Before starting the tightening procedure, prepare everything you need to complete:

• wrench with built-in dynamometer up to 100 N⋅m;
• a set of heads and regular keys;
• key Togh E14;
• vernier caliper for measuring the remaining length of the bolts;
• plate with a marked scale up to 180 degrees;
• new bolts.

The torque wrench is an essential DIY repair tool

Step-by-step instruction

The sequence of performing the operation on the 8 valve engine:

1. Wipe the cylinder head surfaces and dry the bolt holes in the engine block.
2. Install the gasket on the block, align it along the guides.
3. Mount the head from above and insert 10 fixing bolts M10 or M12. If the owner decided to save money and keep the old screws, then they should be no more than 135.5 mm in length.
4. Tighten the elements according to the diagram. The tightening torque should not exceed 20 N⋅m.
5. Then you need to re-stretch the bolts. The second tightening force should be between 70 and 85 N⋅m.
6. Next, tighten the screws with a 90 degree turn in the same sequence. The angle of rotation can be controlled using a special device, which is a plate with an attached scale from 0 to 180 degrees.
7. In accordance with the regulations, you need to turn the bolts again 90 degrees.
8. The fastening of the 8 valve head to the block is complete.
9. After assembling the motor, it is necessary to check the quality of work by starting and warming up the engine. A securely tightened joint between the head and the block should not allow working fluids to pass from the crankcase of the power unit.

Homemade device for controlling the angle of rotation

In the case of a more powerful and modern engine with sixteen valves installed on the machine, for example, the VAZ 21126 model or 126 in abbreviated form, the bolt pulling procedure has its own characteristics.

In order to properly tighten the cylinder head screws on such units, you need:

1. Remove grease from mating surfaces and check that there is no liquid in the bolt holes.
2. Install the gasket, center it and lay the head on top.
3. Insert 10 M10 * 1.25 fixing screws into the guide holes, having previously lubricated the thread with engine oil. If it is decided to use old bolts, which is acceptable for 16 valve heads, then their remaining length should not exceed 98 mm.
4. Carry out preliminary broaching according to the scheme with a torque of 12-20 N⋅m.
5. Increase the degree of tightening to 26-34 N⋅m and re-pass all the bolts in the same sequence.
6. Then it is necessary to turn the screws 90 degrees, while the force will be about 50 N⋅m.
7. Repeat the tightening 90 degrees again, the torque on the wrench will be approximately 80 N⋅m. Some instructions recommend holding up to 20 minutes between turns, but in practice, no advantages of such a scheme have been revealed.
8. After assembling the power unit, you should check the quality of the work performed.

The procedure for pulling the head on 1.8 liter engines, which are 1.6 liter engines with an enlarged cylinder, is completely identical to that described above.

If, in the process of performing work, the correct torque is applied to the bolts, corresponding to the design calculations, then the gasket will be evenly and tightly pressed along the joint, ensuring a reliable and tight connection. It is important to note that if it is required to remove the block head from the engine, then the screws are also loosened according to the scheme established by the regulations. Chaotic loosening of the elements will lead to deformation of the head and the appearance of invisible microcracks.

Sometimes it happens that it is necessary to urgently replace the gasket or change the cylinder head. Such works at the service station cost a lot and in order to save money, you can try it yourself. This work is simple, but requires care, the main thing is to observe the sequence and tightening torque of the cylinder head of the Priora 16 valves.

Here you also need to know that the tightening sequence for 16 cl and 8 cl units is different, so you need to be careful. The torque on the 16 and 8 valve power unit is the same and runs in four circles.

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When is the block tightening necessary?

Tightening the bolts is necessary first of all after you dismantle the cylinder head and reinstall it. Also, tightening can help in some cases, if during operation it has weakened and there is a need to carry it out. In some cases, for example, when the gasket starts to skip a little, this can help.

Adjusting the tightening torque of the bolts for the 16 valve auto

Adjusting the tightening torque is a simple process, and after reading the material and video in this article, you can handle it yourself. It is enough to carry out the tightening once and then you yourself will be able to perform it and at the same time you will be able to help your friends if necessary. It is important to adhere to the scheme for cars with a 19-valve engine and observe the moment.

Required tools

Scheme

The diagram for tightening on a 16 valve motor differs from the diagram for an 8 valve, so we will present both one and the second so that you can compare them.

Just do not mix it up when you install. In any case, before starting work, check the instructions that come with the car. Tightening with different torque on the 16 valve assembly occurs in 2 circles with different torque, and then 2 more circles with a 90 degree turn. Nothing is difficult, which means you can cope on your own.

Stages

In order for the self-tightening of the bolts to be completed successfully and held for a long time, a number of simple rules should be observed:

By following these simple rules, you can guarantee the best tightening and a reliable tight connection.

Place the cylinder head on the block, after making sure that the knees and camshafts are in the top dead center (TDC) position.

The tightening process itself takes place in the 4th circle:

• 1st circle - moment 20 Nm (2 kgf / m);
• 2nd circle - moment 69.4–85.7 N · m (7.1–8.7 kgf · m);
• 3rd circle - turn the bolts 90 degrees;
• 4th circle - another 90 degree turn.

As you can see, everything is simple, if you still have questions, then watch the video. In terms of time, this work does not take more than twenty minutes, but it allows you to save a decent amount, which will be charged from you at the service station.

Video "How to properly tighten the cylinder head bolts"

In this video, a master with extensive experience shows and describes in detail how the cylinder head bolts are tightened correctly. On a Lada Priora car with a 16-cell unit, work is performed according to the same scheme.

Today we brought one of the old customers on the Priora, as it turned out, the jammed pump broke the belt and, as a result, the valves bent.

But progress at AvtoVAZ does not stand still, and if the valves of the tenth family simply bent, then the connecting rods on Prior's 126s also lose their alignment and, if they are not changed, there is a high probability that the engine will start eating oil and, accordingly, your money. Glory to the designers of AvtoVAZ!

But there is no harm without good, there are sets of pistons for 126th motors with grooves that do not bend the valve. In this article, we will describe the procedure for repairing the cylinder head after a timing belt break, as well as replacing the piston. Removal and installation of the timing belt is described in, so we will not dwell on it in detail.

To perform this procedure, the presence of torque wrenches is required!

We begin to disassemble

First, drain the oil and antifreeze. We remove the protective cover, the air filter with nozzles, disconnect the connectors of the ignition coils, the gas cable and the throttle assembly.

We remove the thermostat housing and simultaneously disconnect all the connectors and pipes that come across. We remove all the wiring that interfered with us in the direction of the battery.

We remove the generator. We unscrew the eight nuts on the thirteen holding the intake manifold and remove it. We unscrew all the bolts securing the valve cover, as well as the side engine support.

We unscrew the eight nuts and remove the exhaust manifold.

Remove the timing belt, camshaft pulleys and pump.

In three passes, so as not to deform the part, first we loosen and then unscrew the twenty bolts of the camshaft bearing housing, the head is eight.

Remove the bearing housing. Removing the camshafts, there is a distinctive bead on the intake camshaft.

Also, in several passes, we first loosen, and then unscrew ten cylinder head bolts. Necessarily in the sequence shown in the photo.

Remove the cylinder head. All sixteen valves are replaced.

Cylinder head repair

We mark all hydraulic lifters with numbers using an ordinary clerical stroke and remove them further. An ordinary magnet will help to pull them out. We dry the valves and remove the valve stem seals (valve oil seals), the valve in scrap metal, the oil seals in the trash. We clean out all channels. We take the head for grinding, just in case. After grinding again with kerosene and blowing with air, we begin to collect.

We arrange the freshly bought valves in the sequence in which they will stand in the cylinder head and in turn we begin to grind. Lubricate the valve stem with clean oil, and apply lapping paste to the edge.

We insert the valve in its place and put on the valve stem a valve grinding device. A device for manual grinding is sold in stores, but since we are mechanizing the process in the twenty-first century. We take the old valve and cut off the rod from it, select a rubber tube of such a diameter on it that it would be put on with an interference fit. A rod into a reversible drill, one end of the tube on it, the other on the lapped valve. At low speeds, we begin to grind the valve, constantly change the direction of rotation and periodically press it against the seat, then weaken the force. On average, the valve takes twenty seconds. We take it out and wipe it. The valve is considered lapped if a uniform gray strip with a width of at least 1.5 mm appears on the chamfer.

The same strip should appear on the valve seat.

Manual valve lapping video

For a sixteen valve head, everything is the same only there are twice as many valves.

After lapping, we thoroughly wipe all valves and seats and rinse with kerosene to remove the remnants of the lapping paste. We check for leaks. We twist the old candles and put all the valves in place. We fill in kerosene and wait three minutes, if the kerosene does not run away all is well, otherwise we grind the valves on this cylinder.

We had to grind four valves again, after which the kerosene stopped escaping.

Stuffing new valve seals.

We put the valves in place and dry them. Before this, the valve stems are lubricated with clean oil. Having lubricated with clean oil, we put the hydraulic lifters in place and, covering with a clean cloth, remove the head out of sight. Finished with the cylinder head.

Moving on to the block of cylinders

We remove the pallet. Turning the crankshaft as it is convenient for us, unscrew two bolts on each connecting rod cover. We use the TORX E10 head for this.

We take out the piston together with the connecting rods. To do this, we rest against the connecting rod from below with the wooden handle of the hammer and slightly knock it up. We remove the old inserts and buy new ones of the same size according to the markings on them. Here is another stone in the AvtoVAZ garden, the owner's car from the passenger compartment and into the engine have never climbed, but three pistons were group "B" and one was "C". It turns out that at the factory one cylinder was slightly re-sharpened and simply stuck in an enlarged piston, there are no words. There are no options, we take the "C" group, do not sharpen the engine because of this. We will not touch the root inserts either.

We buy a new piston group that does not bend the valve, connecting rods and connecting rod bushings.

We eliminate the longitudinal play of the crankshaft

On this engine, he was seen. To eliminate it, replace the persistent half rings. Available in standard and repair sizes. We take the first repair size, if they are tight, we will grind it down a little. We unscrew the middle main bearing and gently push the half rings with a screwdriver. The mark on it is in the form of three serifs, shown below.

When the half-ring has come out a little, we turn the crankshaft, it will push it out. Half rings of two types in the front are white and yellow at the back, the grooves on them should look towards the cheeks of the crankshaft.

We put it as we removed the new half rings, if they come in with great effort, you can grind them a little on a fine abrasive bar, just not from the side of the grooves. We check the backlash. We tighten the main bearing with a torque of 8 kgf * m.

We collect the piston

An arrow is knocked out on the top of the piston, it should be directed towards the front of the engine. And there are marks on the connecting rod, which should look the same in turn. Don't mix it up!

Insert one retaining ring into the groove on the piston. We insert the connecting rod into the piston and, having lubricated our own and the piston pin with oil, insert it into place. Insert the second retaining ring. This operation, although it seems simple, will have to suffer. We inspect the assembled structure, all the retaining rings must be clearly in their grooves, otherwise a popping out ring on a running engine can do a lot of trouble.

After assembly, you need to break off the connecting rod bearing cap, since the connecting rod is made in one piece. This is the case on our machines. First, unscrew the bolts. We insert the connecting rod into the teski at the level of the mark shown in the figure with the black arrow and slightly squeeze it, then break it off with a slight movement of the hand. Very scary the first time. We put the cover in place and tighten the bolts so as not to be confused in the future.

Checking the thermal clearance in the piston rings

We lay out each set of rings to each cylinder. In the future, we do not change them in places. In turn, we put each ring in our cylinder and push it a little with the piston approximately to the middle.

We measure the gap with the probes.

Nominal clearance: 0.25 - 0.45 mm.

The maximum clearance for all is 1 mm. But it already smacks of boring.

Installing new rings

First, we install the expanding spring of the oil scraper ring, then the ring itself. The oil scraper ring lock should face the opposite side of the spring lock. Then we install the lower compression ring and finally the upper compression ring. The inscription "TOP" is necessarily embossed on the rings, it should look up. The rings in the piston grooves must necessarily rotate easily.

Assembling the engine

We wipe the crankshaft journals, the cylinder mirror and the connecting rod bearing seats with a clean rag; by the way, you can degrease them. We put new liners in the connecting rod and the cover, so that the tendrils of the liners go into the grooves.

Lubricate the liners, crankshaft journals and cylinders with clean oil. We unfold the piston rings with locks as shown in the figure, the angle between them should be 120 degrees.

We put a mandrel on the piston to compress the rings, having previously lubricated it inside with clean oil. Not forgetting about the direction, the arrow on the piston should be directed to the front of the engine, we put it in our cylinder.

We turn the crankshaft so that the crankpin is at the very bottom. Gently tapping the wooden handle of the hammer push the piston into the cylinder. Remove the mandrel and push the piston down until the connecting rod sits on the crankshaft. We put the connecting rod bearing cover on the bottom, remember about the labels. We tighten the connecting rod cover bolts to a torque of 5 kgf * m. We also repeat with all the other cylinders.

We put in place everything that was removed from the bottom. From above we blow and clean the holes for the cylinder head bolts. We put a new cylinder head gasket and the head itself. We lubricate the bolts with a thin layer of oil, the main thing is without fanaticism. We tighten the bolts in several passes in the reverse order of unscrewing, see the photo at the beginning of the article. The tightening sequence is as follows:

1. first, we tighten everything with a torque of 2 kgf * m
2. then we tighten everything with a torque of 7 - 8 kgf * m
3. turn 90 degrees
4. turn again 90 degrees

We install hydraulic lifters, camshafts and a camshaft bearing cover. All rubbing surfaces are lubricated with clean oil. Before installing the camshaft bearing cover, lubricate the perimeter and rims around the spark plug wells with a thin layer of sealant. We tighten the bearing cap bolts, in the reverse order of unwinding, to a torque of 2 kgf * m, see the photo at the beginning. Well, then we install all the parts in the reverse order of removal. We fill in all the liquids and start, it may not start right away, this is normal. At the first start, it will smoke well until the oil on the cylinders burns out, we look to see that the oil pressure lamp goes out. We give it a minute to work and turn off, we suddenly look where something has flowed. We start up several more times, constantly increasing the operating interval, bring it to the operating temperature, constantly checking the oil and antifreeze, we also pay attention to the fact that there would be no extraneous noise. We give it a rest for an hour and again at idle speed for about an hour, we constantly monitor the temperature. Well, then the running-in if sharpened, if not, then you can go only the first thousand kilometers, try not to raise the speed above 3000 and not be towed.

2016-12-10