Drive Belt Replacement: When to Check and How to Replace

The drive belt used in cars drives the auxiliary components of the engine. Due to the rotation of the crankshaft, it transmits torque, ensuring the operation of attachments. The drive belt has its own resource, a different length, a different number of streams and teeth. 

Drive belt function

The drive belt is necessary for transmitting torque from the crankshaft, due to which the auxiliary units rotate. The moment is transmitted due to friction (V-ribbed belt) or meshing (toothed belt). From the belt drive involved the operation of the generator, without which it is impossible to charge the battery and maintaining a constant voltage on-board network. The air conditioning compressor and power steering pump also operate with a belt drive. In some cases, the water pump is also driven by a timing belt (1.8 TSI VAG engine).

Belt Life

Due to design features (elasticity and flexibility), the average belt resource is 25 hours of operation or 000 kilometers. In practice, the life of the belt may vary in one direction or another, depending on the following factors:

• belt quality;
• the number of units driven by one belt;
• wear of the crankshaft pulley and other units;
• belt installation method and proper tension.

Regular inspection of drive belts

A periodic check for belt tension should be carried out seasonally. Belt diagnostics are performed when the engine is off. The level of tension is checked by pressing a finger, while the deflection should not be more than 2 cm. A visual inspection reveals the presence or absence of cracks. At the slightest damage, the belt must be replaced, otherwise it may break at any time. 

Also, checking the belt is carried out in some cases:

• insufficient battery charge;
• the steering wheel (in the presence of the hydraulic booster) began to rotate tightly, especially in the cold season;
• the air conditioner is slightly cold;
• when the auxiliary units are working, a creak is heard, and when water gets on the belt, it rotates.

When and how to change the drive belt

The drive belt must be changed according to the regulations specified by the manufacturer, or in the presence of the above belt wear factors. The minimum belt resource is 50000 km, wear with less mileage indicates a backlash in one of the drive pulleys or poor belt quality.

Depending on the engine modification and auxiliary drive design, change the belt yourself. The difference is in the type of tension:

• bolt tension
• stretch roller.

Also, the units can be driven by one belt, or individually, for example: a Hyundai Tucson 2.0 car is equipped with air conditioning and a power steering pump, each of which has an individual belt. The power steering pump belt is driven from the generator pulley, and the air conditioner from the crankshaft. The tension of the air conditioner belt is carried out by a roller, and the generator and power steering pump by a bolt.

The process of replacing drive belts on the example of Hyundai Tucson:

• the engine must be turned off, the gearbox selector must be in “P” mode or in 5th gear with the hand brake engaged;
• the front right wheel must be removed to access the crankshaft pulley;
• To access the HF pulley, remove the plastic boot that protects the belts from dirt;
• under the hood, the first is the power steering pump belt, for this you need to loosen the mount and bring the pump closer to the engine;
• the generator belt is removed by loosening the mount, similar to the power steering pump;
• the last is removed the belt on the air conditioning compressor, here the tension is made by a roller, which is fastened with a bolt to the side, and depending on the tightening force of the bolt, the belt tension is adjusted; just unscrew the bolt slightly and the belt will loosen;
• the installation of new belts is carried out in the reverse order; put the boot back in the last turn after checking the operation of the belts.

Pay special attention to product quality, try to purchase original spare parts, in order to avoid the risk of premature wear.

How to tighten, tighten or loosen the drive belt

On the same example:

• the air conditioner belt is pulled by a roller mechanism using a side bolt that moves the roller back and forth; to tighten the bolt, turn it clockwise, to loosen it counterclockwise (deflection of a new belt no more than 1 cm);
• the generator belt is pulled by a special long screw, when it is twisted, the generator is pushed back, creating a tension, in the opposite direction the belt is loosened
• to tighten or loosen the power steering pump belt, you need to loosen the assembly mounting bolt, select the required tension and tighten the bolt, if there is not enough tension, use the mount and rest between the engine and the pump, moving the pump forward in the direction of the car.

Why the belt started to whistle

 The belt whistle occurs for the following reasons:

• when driving, water got on the belts, cranking relative to the pulley occurred;
• malfunction of bearings of the generator or power steering pump, increase the load on the belt;
• insufficient tension or vice versa;
• low-quality product.

If the belts are in good condition, but a squeak occurs periodically, it is recommended to purchase a spray conditioner that tightens the belt, extending its service life.

Questions and answers:

When do I need to replace the drive belt? This can be determined by the external condition of the belt. A worn element will have multiple small cracks, and in some cases it may be frayed.

When to change the drive belt tensioner? Rust and cracks have appeared, the bearing is worn out (it will whistle during operation), the valve timing has shifted (the belt is noticeably weakened).

Do I need to change the drive belt? Necessarily. This element provides communication of the crankshaft with the gas distribution mechanism and the generator. If the belt breaks, the motor will not run and in some cases the valves will bend.