Tightening torque of cylinder head VAZ-2112 (16 valves): scheme

The tightening torque of the VAZ 2112 cylinder head (16 valves) is very important, since deformation occurs during uneven installation of the head. This leads to the fact that after disassembly, it will be necessary to grind at least 2 mm from the surface of the block head. If you observe all the tightening torques, then you will not have to sharpen the head, and if you need to do this, then no more than a quarter of a millimeter.

Head construction

The 16-valve engine uses a block head in which the following elements are located:

1. Two camshafts. They are with five supports, cast from cast iron, each with 8 cams. It is not possible to install an exhaust camshaft (and vice versa) instead of an intake camshaft.
2. 16 valves. They are mounted on guide bushings.
3. Saddles are installed directly on the head of the block, which are in contact with the valve plates.
4. Hydraulic expansion joints in the amount of 16 pieces.

Camshafts are installed on the cylinder head bearings. Compliance with the tightening torque of the cylinder head VAZ-2112 (16 valves, 1.5 liters) allows for the normal functioning of the engine. This will also avoid expensive milling of the surface after the next dismantling of the head.

Preparing to replace the cylinder head gasket

When removing the head of the unit, be sure to change the gasket - you cannot reuse it, as this will lead to a breakdown. It also needs to be changed if a leak of antifreeze or engine oil is detected in the area where the unit and head are connected. Often leaks result from damage to the head itself due to excessive heat. If you do not observe the tightening torque of the VAZ-2112 cylinder head bolts (16 valves), damage to the gasket and leakage of liquids may occur.

Preparatory work before replacing the gasket:

1. Disconnect the negative terminal from the battery.
2. Install the piston in the first cylinder to the position corresponding to the top dead center.
3. Completely drain the liquid from the cooling system - to do this, first unscrew the plug at the bottom of the radiator, then in the engine block.
4. Be sure to relieve pressure in the fuel system - there is a special fitting in the ramp for this.
5. Remove the front pipe mounting nuts from the exhaust manifold.
6. Remove the thermostat.
7. Remove the nut that secures the bracket to the fluid pump pipe.
8. Loosen the nut that secures the bracket to the manifold (exhaust). After that, take him aside so that he does not interfere with the work.
9. Disconnect the wiring block from the oil sensor and on the VAZ-2111 modification motors you need to unscrew or loosen the nuts that secure the support and support brackets.

Removing the block head

After preparatory work, you need to completely remove the head. To do this, the following manipulations are performed:

1. Disconnect the white block from the DPKV, for this you need to squeeze the plastic latch.
2. Remove the plastic decorative panel and the metal cover from the block head.
3. Remove the timing belt. To do this, unscrew the nut of the tension roller and remove it completely.
4. The camshaft pulley needs to be fixed with a screwdriver - try to prevent turning.
5. Remove the camshaft mounting bolt and remove it completely.
6. The second camshaft is removed similarly.
7. Unscrew the ten bolts that secure the head to the block.

After that, you can completely remove the cylinder head. The tightening torque of the VAZ-2112 cylinder head (16 valves) under the turbine is the same as without it.

Valve System Features

On a VAZ-2112 vehicle, the design of the valves is very similar to that used in the VAZ-2110 modification engines. Only they have the diameter of the rods and plates is slightly smaller. Dimensions:

1. The inlet valve is a plate with a diameter of 29 mm, a stem of 6.975 mm.
2. The exhaust valve is a plate with a diameter of 25.5 mm, a stem 6965 mm.

A spring is installed on each valve; its length without load is 38.19 mm. With a load of 240 Newton, it decreases to 32 mm. If you act on a spring with a load of 550 Newton, its length is reduced to 24 mm.

Hydraulic pushers

The valves are driven by cams on camshafts and hydraulic pushers. These elements are located inside the guide holes. With the help of hydraulic pushers, it is possible to automatically eliminate the gaps in the valve mechanism. Therefore, when operating a car, it is not necessary to adjust the thermal clearances of the valves.

In order for the hydraulic pushers to work in normal mode, oil comes from the lubrication system to them. It is fed through special channels in the engine and cylinder head block. Oil passes through these channels and to lubricate the necks on the camshafts. In the channel there is a valve with which the oil does not drain from above after the engine is turned off. This allows you to maintain the system in normal mode until it stops.

Camshafts

When repairing the head, it is necessary to check the condition of the camshafts. When assembling, follow the instructions and maintain the tightening torque of the VAZ-2112 cylinder head (16 valves). Such a motor is installed on the Priore - it is quite powerful, has excellent characteristics and does not require frequent care. Two camshafts drive the intake and exhaust valves.

Camshafts rotate in special sockets that are located directly in the head. The difference between the camshafts is that there is a small belt on the inlet. It is located near the very first support. To prevent axial movement, there are persistent collars - they are located on both sides of the support in front. Ahead on both camshafts there are self-clamping type oil seals.

How to repair

In order to repair the voices of the block, you will need the following tools:

1. Device for compressing valve springs. You can use both "store" and homemade. The main thing is that it is convenient to work.
2. Device for extruding valve stem seals.
3. Mandrel in the form of a tube for installing caps.
4. “10” wrenches, hexagons, tweezers and screwdrivers.

Perform the following manipulations:

1. Carry out all the steps to remove the head and camshafts.
2. Remove all valves using a special device.
3. Remove the valve stem seals.
4. Replace and grind the valves. Valves need to be changed if there are damages - burnouts, violation of geometry. Be sure to sign on which sockets you grind the valve - otherwise the tightness will be violated.
5. Assemble all valve drive mechanisms - hydraulic pushers, springs, fix them with crackers.

All assembly steps of the assembly are carried out in the reverse order, only one peculiarity must be taken into account: adhere to the recommended values ​​for the tightening torque of the VAZ-2112 cylinder head (16 valves). The photo shows the tightening sequence.

How to tighten the cylinder head bolts

Be sure to tighten according to the scheme given in the article. In order to tighten the bolts, you need to perform a few simple steps:

1. Install a new block head gasket, place it on the centering bushings.
2. Install the head and bait the bolts of its fastening.
3. Start tightening with a moment of 20 N * m. If the scale is in "kgf / m", then divide by 10.
4. In the second run, you need to tighten all the bolts according to the scheme 90 degrees.
5. For the third call, they turn another 90 degrees.

Do not use bolts with a length of 95 mm or more. In general, the procedure is quite simple, but a torque wrench is required - without it, it will not be possible to maintain the correct tightening torque of the VAZ-2112 cylinder head (16 valves).