How to determine the wear of the timing chain on the VAZ 2106 and replace it with your own hands

In the engines of the classic Zhiguli series VAZ 2101–2107, the gas distribution mechanism (timing) is driven by a two-row chain. The service life of the part is quite long and is at least 100 thousand kilometers. If symptoms of critical wear appear, it is advisable to replace the entire chain drive, together with the gears. The procedure is time-consuming, but uncomplicated, a skilled motorist will cope with the task without any problems.

Drive design at a glance

In order to independently change the chain and related elements, you need to know the structure of this part of the power unit. The mechanism that drives the camshaft of the VAZ 2106 engine includes the following parts:

• a small drive sprocket is mounted on the crankshaft;
• large idler gear;
• the upper large gear is bolted to the end of the camshaft with a bolt;
• double-row timing chain;
• tensioner shoe, supported by a plunger rod;
• damper - a metal plate with a wear-resistant pad;
• chain runout pin is installed next to the lower sprocket.

When rotating, the chain is held on both sides by the pads of the damper and the tensioner

In the old versions of the “six”, a mechanical tensioner plunger was installed, where the stem extends under the influence of a spring. The updated modification of the car is equipped with a hydraulic plunger device.

During engine operation, the timing chain must be in a taut state, otherwise runout, accelerated wear and skipping of the links over the teeth of the gears will occur. A semicircular shoe is responsible for the tension, supporting the part on the left side.

Learn more about timing chain tension: https://bumper.guru/klassicheskie-modeli-vaz/grm/kak-natyanut-tsep-na-vaz-2106.html

After the camshaft sprocket (in the direction of rotation), a damper plate is installed, pressed against the chain drive. To prevent the element from jumping off the lower gear as a result of strong stretching, a limiter is installed next to it - a metal rod screwed into the cylinder block.

The updated versions of the "six" were equipped with automatic tensioners operating from oil pressure

The drive mechanism is located at the front end of the engine and is closed by an aluminum cover in which the front crankshaft oil seal is installed. The lower plane of the cover is adjacent to the oil pan - this feature must be taken into account when disassembling the unit.

Purpose and characteristics of the circuit

The timing drive mechanism of the VAZ 2106 motor solves 3 problems:

1. Rotates the camshaft, opening the intake and exhaust valves in the cylinder head.
2. It drives the oil pump by means of an intermediate sprocket.
3. Transmits rotation to the ignition distributor shaft - distributor.

The length and number of links of the main drive element - the chain - depends on the type of power unit. On the "sixth" models of "Zhiguli" the manufacturer installed 3 types of engines with a working volume of 1,3, 1,5 and 1,6 liters. In the VAZ 21063 engine (1,3 l), the piston stroke length is 66 mm, on modifications 21061 (1,5 l) and 2106 (1,6 l) - 80 mm.

Many manufacturers indicate information on the number of links directly on the packaging.

Accordingly, two sizes of chains are used on power units with different displacement:

• 1,3 liter engine (VAZ 21063) - 114 links;
• motors 1,5-1,6 liters (VAZ 21061, 2106) - 116 links.

How to check the length of the chain during the purchase without counting the links? Pull it out to its full length, laying both parts close to each other. If both ends look the same, this is a 116 link part for engines with a large piston stroke (1,5-1,6 liters). On a short chain for the VAZ 21063, one extreme link will turn at a different angle.

If the ends of the stretched chain look the same, there are 116 sections

Signs of critical wear on a part

During the operation of the vehicle, the chain drive is slowly stretched. Deformation of metal joints does not occur - the reason for the phenomenon lies in the abrasion of the hinges of each link, the formation of gaps and backlash. Within 1-2 bushings, the output is small, but multiply the gap by 116 and you will get a noticeable elongation of the element as a whole.

How to determine the malfunction and the degree of deterioration of the chain:

1. The first symptom is extraneous noise coming from under the valve cover. In especially advanced cases, the sound turns into a loud rumble.
2. Remove the valve cover and check that the marks on the camshaft sprocket and crankshaft pulley match the corresponding tabs on the housing. If there is a shift of 10 mm or more, the element is clearly stretched.
   

   The correct operation of the mechanism is determined by the simultaneous coincidence of the marks on the crankshaft pulley and the camshaft sprocket
3. Tighten the chain, start the engine and set the marks again. If the part is significantly lengthened, the indicated measures will not give results - the extension of the plunger is not enough to pick up the slack.
4. With the valve cover removed, check the technical condition of the damper. Sometimes an over-stretched chain drive simply cuts off its lining or the entire part. Metal and plastic debris fall into the oil sump.

Once, in the process of diagnosing the "six" motor, I had to observe the following picture: the lengthened chain not only broke the damper, but also made a deep groove in the cylinder head housing. The defect partially affected the contact plane of the valve cover, but cracks and engine oil leaks did not form.

When the damper is torn off, the chain rubs against the edge of the cylinder head platform and makes a groove

A chain stretched by 1 cm or more is able to jump 1-4 links along the gears. If the element “jumped” over one section, the gas distribution phases are violated - the motor vibrates strongly in all operating modes, significantly loses power and often stalls. A clear symptom is shots in the carburetor or exhaust pipe. Attempts to adjust the ignition and adjust the fuel supply are useless - the "shaking" of the engine does not stop.

When the chain is displaced by 2-4 teeth, the power unit stalls and will no longer start. The worst-case scenario is a piston hitting the valve plates due to a large valve timing shift. Consequences - disassembly and expensive motor repair.

Video: determining the degree of wear of timing gears

Engine Timing Chain and Sprocket Wear Determination

Replacement Instructions

To install a new chain drive, you need to purchase a set of spare parts and consumables:

• double-row chain, suitable for a specific type of engine;
• 3 gears - two large and one small (sold as a set);
• tensioner shoe;
• damper plate;
• power unit front cover gasket;
• high temperature silicone sealant.

Some manufacturers produce complete repair kits that include all the parts you need.

If, when diagnosing problems, you find oil leaks under the crankshaft pulley, you should purchase a new oil seal built into the front cover. The part is easy to change in the process of disassembling the timing drive.

Why is it recommended to change all drive parts, including gears:

• during a long period, while the chain was stretched, the teeth of the sprockets also had time to wear out;
• for the same reason, the damper and tensioner linings were worn out;
• the repair operation is very time consuming, it is impractical to repeat it because of each worn out drive element.

The teeth of the worn sprockets are literally licked and allow the chain to slip.

Tool and working conditions

Of the special tools, you will need a 36 mm box wrench to unscrew the nut (ratchet) holding the crankshaft pulley. Since the ratchet is recessed, it is much more difficult to grip it with an open-end wrench.

With a special long-handled wrench, it is easy to rip off the ratchet nut when unscrewing

The rest of the toolbox looks like this:

• a set of open-end wrenches and sockets with a ratchet and a crank;
• flat screwdrivers - regular and reinforced;
• mounting blade;
• passages;
• a hammer;
• rags, protective gloves.

Replacing the timing chain drive is carried out using a conventional garage tool.

It is most convenient to replace the timing chain on a viewing ditch in a garage. In extreme cases, an open area is suitable, but then you will have to lie down on the ground under the car to disassemble the unit.

Preliminary disassembly

The purpose of the preparatory stage is to provide easy access to the front cover of the power unit and the timing drive. What needs to be done:

1. Place the car on the inspection hole and turn on the handbrake. For ease of disassembly, allow the engine to cool down to 40-50 ° C.
2. Go down into the ditch and dismantle the oil pan protection. Immediately unscrew the 3 front bolts connecting the sump to the end cap, loosen the nut on the bottom mounting of the generator.
   

   To loosen the belt, you need to unscrew the lower mount of the generator
3. Open the hood and remove the air filter box attached to the carburetor.
   

   The air filter housing blocks access to the valve cover nuts
4. Disconnect the pipes passing over the valve cover. Disconnect the starter drive cable (in the common people - suction) and the accelerator rod.
   

   Thrust from the gas pedal is fixed on the valve cover, so it must be dismantled
5. Remove the valve cover by unscrewing the 10 mm wrench fastening bolts.
   

   The valve cover is removed after unscrewing 8 nuts M6
6. Disconnect the electrical cooling fan connector.
7. Loosen and unscrew the 3 bolts holding the electric fan to the main radiator, pull the unit out of the opening.
   

   The cooling fan is attached to the radiator with three 10mm bolts.
8. Loosen the nut on the generator mounting bracket with a spanner wrench. Using a pry bar, slide the housing towards the engine, loosen and remove the drive belt.
   

   To loosen the belt, the generator housing is fed towards the cylinder block

In addition to the listed parts, you can remove other items, such as the battery and the main radiator. These actions are optional, but will help increase access to the chain mechanism.

At this stage, it is recommended to clean the front of the motor as much as possible from dirt and oil deposits. When you remove the timing cover, a small opening in the oil sump will open up where debris can enter.

Disassembly of the injector "six" is carried out in the same way, only together with the air filter housing it is necessary to dismantle the corrugated pipe leading to the throttle, the crankcase ventilation pipes and the adsorber.

Video: removing the electric fan and radiator VAZ 2106

Cooling radiator, dismantling, removal from car...

Removing and installing a new chain

If this is your first time disassembling a camshaft chain drive, strictly adhere to the sequence of work:

1. Loosen the ratchet nut with a 36mm wrench. To loosen, fix the pulley in any convenient way - with a mounting spatula, a powerful screwdriver or a pipe wrench.
   

   It is more convenient to unscrew the ratchet nut from the inspection ditch
2. Remove the pulley from the crankshaft by prying from different sides with a flat screwdriver.
   

   Tight pulley pops off easily when the edge is pryed with a pry bar
3. Loosen the 9 screws securing the front cover using a 10mm wrench. Use a screwdriver to separate it from the mounting flange and set aside.
   

   The front cover is held on by six bolts and three 10 mm wrench nuts.
4. Bend the edges of the lock washers on the bolts of the two large sprockets. Grasping the flats at the end of the crankshaft with a wrench and holding the mechanism from rotating, loosen these bolts with another 17 mm wrench.
   

   The locking plates on the gear bolts are unbent with a screwdriver and a hammer
5. Align the mark on the top gear with the tab on the camshaft bed.
   

   Before removing all the stars, you need to set the mechanism according to the marks
6. Dismantle the damper and the tensioner plunger by unscrewing 2 fixing screws with a wrench 10 mm.
   

   The damper is bolted with two M6 bolts, whose heads are located outside the cylinder head
7. Finally remove the bolts and remove both sprockets by carefully lowering the chain down.
   

   When all the marks are set and the chain is loose, you can finally unscrew the bolts and remove the gears
8. Unscrew the limiter, remove the chain and the small lower gear without losing the keys. Loosen the tensioner shoe.
   

   If the marks are correctly aligned, then the sprocket key will be on top and will not be lost.

More about the timing chain shoe: https://bumper.guru/klassicheskie-modeli-vaz/grm/natyazhitel-tsepi-vaz-2106.html

During the disassembly process, you may encounter a situation when the chain stretched over the norm has destroyed or cut the damper, and the debris fell into the crankcase. Ideally, they should be removed by dismantling the pallet. But since the oil pump is equipped with a screen, and waste always accumulates in the crankcase, the problem is not critical. The probability that the remains of the part will interfere with the intake of oil is almost zero.

When replacing the chain on my father's "six", I managed to drop a piece of plastic damper that had fallen off into the crankcase. Attempts to extract through a narrow opening were unsuccessful, the fragment remained in the pallet. Result: after the repair, the father drove more than 20 thousand km and changed the oil, the plastic is in the crankcase to this day.

Installation of new parts and assembly is carried out in the following order:

1. Clean the adjacent surfaces of the cover and cylinder block by covering the crankcase with a rag.
2. Lower the new chain into the opening of the cylinder head and secure it with a pry bar so that it does not fall.
   

   To prevent the chain from falling into the opening, fix it with any tool
3. Since you aligned all the marks before removing the chain, the keyway on the crankshaft should line up with the mark on the block wall. Carefully fit the small sprocket and put on the chain.
   

   Check the position of the marks before installing the chain drive
4. Install a new damper, limiter pin and tensioner shoe. Bolt the intermediate and upper gear by throwing the chain.
5. Install the plunger and tension the chain drive using the spring mechanism. Check the position of all marks.
   

   When the outer bolt is loosened, a plunger mechanism is activated that tensions the chain.
6. Apply sealant to the flange of the cylinder block and screw on the cover with the gasket.

Further assembly is carried out in the reverse order. After attaching the pulley, it is recommended to re-verify that the marks are in the correct position. The notch on the side of the pulley should be opposite the long strip on the front cover.

About the oil pump device: https://bumper.guru/klassicheskie-modeli-vaz/dvigatel/maslyanyiy-nasos-vaz-2106.html

Video: how to change the chain on a VAZ 2101-07

How to Replace the Timing Chain in a VAZ and the Unforeseen

Is it possible to shorten a stretched chain

Theoretically, such an operation is quite possible - it is enough to knock out the cotter pin of one or more links and reconnect the chain. Why is such a repair very rarely practiced:

1. It is difficult to estimate the degree of elongation of the element and the number of links to be removed.
2. There is a high probability that after the operation the marks will no longer align by 5-10 mm.
3. A worn chain will definitely continue to stretch and soon begin to rumble again.
4. The worn gear teeth will allow the links to skip easily when the chain is extended again.

Not the last role is played by economic expediency. A spare parts kit is not so expensive that it costs time and effort to try to repair the part by shortening it.

Replacing the timing chain drive will take an experienced craftsman approximately 2-3 hours. An ordinary motorist will need twice as much time without taking into account unforeseen breakdowns. Set aside part of the day off for repairs and do the work without haste. Do not forget to match the marks before starting the motor and make sure that the mechanism is assembled correctly.