Timing chain drive VAZ 2101: malfunctions, repairs, adjustment

Timing belt with chain drive on VAZ 2101

The “kopek”, like all other “classic” models, has a timing chain drive. The mechanism consists of a double-row metal chain and additional elements that ensure its tension and prevent vibrations. The well-coordinated operation of the motor directly depends on the integrity and serviceability of each part of the mechanism. The chain drive connects the crankshaft and camshaft and ensures their synchronous operation. When the shafts rotate, the pistons in the engine cylinders are set in motion, and the valves in the cylinder head (cylinder head) open and close in a timely manner.

The main elements of the VAZ 2101 timing drive are a chain, a damper, a shoe, a tensioner and sprockets

Tranquilizer

The damper performs the function of damping circuit vibrations. Without it, the chain may jump or fly off the sprockets of the timing mechanism. If the damper breaks down, the drive may simply break off. Such a nuisance is possible at high engine speeds. If the chain breaks, the pistons and valves are damaged, requiring expensive repairs. Therefore, the condition of the damper must be monitored and replaced in a timely manner. The part is a durable metal plate with special holes for fastening.

The chain damper dampens its vibrations when the engine is running.

Opposite the damper there is a shoe, which is also responsible for calming and tensioning the chain. It is made of a special polymer material, which gives the part high wear resistance.

The tensioner shoe is responsible for tensioning the chain and damping vibrations together with the damper

Tensioner

The “penny” chain drive tensioner prevents the chain from loosening when the motor is running. The element comes in several types:

• auto;
• mechanical;
• hydraulic.

Automatic tensioners began to be produced recently, but with regard to this part, it is already possible to note the pros and cons. The main positive point is that there is no need to make periodic adjustments, i.e. the drive is constantly in tension. The disadvantages include fairly quick failure and high cost of the part. In addition, based on reviews from car enthusiasts, the auto tensioner does not tension the chain very well.

The operation of hydraulic devices is based on the supply of oil under pressure from the engine lubrication system. With this design, the driver does not need to worry about periodically tightening the chain. However, over time, the part may malfunction, which manifests itself in the form of jamming of the mechanism.

The VAZ classic uses a mechanical tensioner. The part has a significant drawback: over time, it becomes clogged with small particles, the plunger jams and the device loses its ability to produce tension.

The chain tensioner is designed to keep the chain taut at all times.

Chain

One of the key elements of the timing chain drive is the chain itself, made of metal and having a certain number of links: on the VAZ 2101 there are 114 of them. Compared to a belt drive, the chain is more reliable and has a longer service life.

The chain is considered a more reliable element compared to the belt

Depending on the quality of the chain and the operating conditions of the vehicle, it is replaced every 60–100 thousand km. There are cases that a part lasts for 200 thousand km, but it’s hardly worth the risk, because a broken chain will result in a much more expensive repair than its timely replacement.

The chain is tightened every 10 thousand km, even in the absence of signs indicating sagging.

When is stretching necessary?

Chain tensioning is required in the following cases:

• after engine repair;
• after replacing the product;
• when stretched after prolonged use.

Timing belt VAZ 2101
In the first two cases, it is clear that checking the tension is necessary, since the chain was removed or replaced. In addition, you should also check that the alignment marks match. These marks are located on the crankshaft and camshaft. You can determine the need for tension by the sounds of the engine running. If the tension is weak, then during its operation extraneous noises are heard in the place where the chain drive is located. At the same time, timing parts wear out faster. Therefore, when checking the tension, it is necessary to pay attention to the condition of the damper and the shoe.

Timing tensioner shoe

If the tension is weak, the links can jump several teeth, then the valve timing will be disrupted. In this case, the car may stall, not start, and the speed will fluctuate. You can use a flathead screwdriver to check. It needs to be inserted and, using as a lever, pressed on the chain. It should not bend and be stretched like an arrow. Do not put too much pressure on the drive, although the part is metal, it is subject to deformation.

The video below looks at a VAZ 2101 car, in which a clattering sound is heard when the engine is running. It shows in detail how to check the condition of the damper, the shoe, and how to carry out tension.

Chain mechanism fault detection

The timing drive, equipped with a chain, is structurally located inside the engine. To determine the condition of the parts of this mechanism, it is necessary to partially disassemble the motor. The fact that there are problems with the chain or drive elements is indicated by characteristic signs.

The chain is noisy

A circuit can have different types of noise:

• noise under load;
• knocking on a warm engine;
• extraneous sounds when cold;
• constant noise with a metallic character.

If the motor begins to make sounds that are uncharacteristic of its normal operation, it is necessary to find out as soon as possible what problems have arisen with the chain drive and eliminate them. If this is not done, wear on the timing drive elements will increase, which can lead to costly repairs.

Video: chain knocking in a VAZ “classic” engine

Timing drive components may fail prematurely for the following reasons:

• the use of oil not specified by the car factory, or its untimely replacement;
• use of low-quality parts;
• low lubricant pressure in the engine;
• failure to comply with engine maintenance regulations;
• low quality of repairs.

Often the chain is noisy due to stretching or problems with the tensioner. Attempts to tighten it turn out to be useless, and the engine sounds like a diesel engine. The sound most often appears on a cold engine when idling.

The timing chain stretches over time, so it needs to be periodically tightened or replaced

Jumped the chain

With high mileage of the vehicle, the timing chain stretches. As a result, it can simply jump to other teeth of the camshaft or crankshaft gears. This problem may occur when the timing drive parts are damaged. If the chain jumps by at least one tooth, the ignition is greatly shifted and engine operation becomes unstable (sneezes, shoots, etc.). To fix the problem, you will need to check the integrity of the parts, and if damage is detected, make repairs.

Installing the piston of the fourth cylinder in the TDC position on a VAZ 2105

Installing the piston of the fourth cylinder to the top dead center position on a VAZ 2105 car is done to adjust the valve clearance, or when disassembling the gas distribution system, in this case, setting the top dead center is necessary to ensure against failure of the valve timing during dismantling work. Failure of the valve timing causes unstable operation of the engine, and sometimes its complete failure.

The piston of the fourth cylinder is installed according to the marks located on the camshaft drive sprocket, the camshaft bearing cover housing, as well as by aligning the marks on the crankshaft pulley with the marks stamped on the camshaft drive chain cover.

When the marks coincide, the piston of the first and fourth cylinder may be in the top dead center position. Check the valves to see which piston is in the top dead center position and, if necessary, rotate another circle.

If the marks do not match, then the phase is out of order and in order to restore it, you will have to throw the camshaft drive sprocket onto the required number of chain links.

To carry out repair work, you will need a standard set of tools and a special wrench for the crankshaft pulley. The repair procedure is as follows:

If the marks on the pulley do not match, it is necessary to remove the camshaft drive sprocket and tighten the crankshaft until the marks match. At this point, the repair work to install the piston of the fourth cylinder in the top dead center position on the VAZ 2105 has been completed.

Installing the chain by marks

The need to install marks on the timing mechanism may arise during the repair process or when the chain is severely stretched. If the marks do not match, the stable operation of the motor is disrupted due to a phase shift. In this case, an adjustment is required. The work is carried out with the following tools:

• Screwdriver Set;
• key for rotating the crankshaft;
• a set of keys.

To install the chain according to the marks, you will need a standard garage tool kit.

We carry out the procedure according to the following instructions:

1. We dismantle the air filter box and the valve cover with the seal by unscrewing the fasteners.
2. Loosen the tensioner clamp, press the screwdriver against the shoe and tighten the nut.
3. Using a 38 mm wrench or a crank, turn the crankshaft until the marks on its pulley and the timing cover match, and the mark on the camshaft sprocket should be located opposite the protrusion cast on the body.
4. If any of the marks do not coincide, turn on the fourth speed and unbend the lock washer on the camshaft sprocket.
5. We unscrew the bolt and remove the gear.
6. Remove the chain from the sprocket and set the desired position (step 3). After installing the marks, we perform reverse assembly.

   
   You can turn the crankshaft with a 38 mm spanner.

Video: how to set timing marks on classic Zhiguli cars

replacing the timing belt VAZ 21013.