When and how should you change your timing belt?

Rhythm is important in any situation. Music, cooking, and even your engine! Did you know that a seemingly insignificant timing belt actually controls the rhythm of your entire engine? The timing belt ensures that all the components inside your engine run in sync.

Therefore, changing your timing belt is an important maintenance task. You should know when and how to change your timing belt.

What is a timing belt? What does it do?

The timing belt, also called the cam belt, is a key component that connects the crankshaft and camshaft of the engine. It synchronizes the movement of the crankshaft and camshaft. Sometimes, it also provides power for the water pump, oil pump and injection pump. Its main functions are:

• Maintaining the precise fit between the valve and the piston
• Controlling the rhythm of the four strokes of the engine's intake, compression, combustion and exhaust

With the improvement of design, many cars have returned to using timing chains. The difference between the timing chain and the timing belt is still relatively large, and the timing chain has a longer life.

When should you change your timing belt?

The timing belt is made of rubber, and after years of continuous high-temperature cycles, the rubber begins to age and eventually causes the belt to break. The service life of the timing belt may also vary depending on the model. Generally, the timing belt should be replaced every 60,000 to 100,000 miles (about 96,000 to 166,000 kilometers).

For some Japanese models such as Honda and Toyota, the recommended replacement cycle is about 96,000 kilometers or 6 years. Please refer to your vehicle owner's manual for details.

If you do not replace the timing belt at the recommended time, it may cause complete engine failure, broken or bent valves, damage to the cylinder head or camshaft, and damage to the piston and cylinder wall. In this case, you should consider replacing the engine.

How to replace the timing belt?

If you have some hands-on skills and the right tools, you can try to replace the timing belt yourself.

Tools required:

• New timing belt kit
• Socket wrench set
• Belt removal tool or special tensioner tool
• Grease
• Jack and stand

1. Buy a new timing belt or chain

Before replacing, buy a new timing kit based on your vehicle information. This belt can be bought at any auto parts store.

2. Remove accessories and protective covers

Remove the engine cover, antifreeze pipes, air conditioning belts, generator belts and other accessories, and carefully remove the timing belt cover to expose the belt structure.

3. Align the timing mark

Tighten the crankshaft bolt with a wrench or socket and rotate the engine until the timing mark on the crankshaft pulley is aligned with the 0° mark on the timing scale.

Make sure the camshaft is fully aligned with the timing mark on the crankshaft.

4. Determine if the harmonic balancer pulley needs to be removed

Typically, the belt cover will fit over the end of the crankshaft and cannot be removed through this pulley without first removing the crankshaft. Note that if this is the case, additional seals will be required for reinstallation and a special crankshaft pulley and gear removal calibration tool may be required.

5. Remove the bolts or screws that hold the timing cover in place

Remove this cover from the engine. Some engines have a two-piece timing cover. Remove any components or accessory drive belts that would interfere with the removal of the timing belt cover.

6. Are the crankshaft and camshaft timing marks properly aligned?

Many engines have scale lines on the pulleys and/or sprockets that must be aligned with corresponding marks on the block, cylinder head, or accessory shaft. On some engines, the scale line on the camshaft sprocket aligns with the parting line of the first camshaft bearing seat.

7. Check for signs of oil leaks around the belt.

Check the camshaft and crankshaft seals, as well as the valve cover and oil pan. Check the water pump and water pump bypass hose for coolant leaks. Leaks should be repaired before installing a new belt.

8. Remove the old timing belt

Loosen the tensioner and slide off the old belt. Do not remove it completely unless you need to replace the tensioner. Also check the water pump and tensioner for damage such as dents or cracks. It is recommended to replace them together.

9. Install the new belt

Correctly install the new belt into the gear teeth and adjust the timing belt torque to the correct specification, paying special attention to the "torque" specification on the engine manual, especially the crankshaft pulley mounting bolts, which usually have very high torque specifications. Then, pull the tensioner to ensure that the belt tension is moderate.

Summary

Although the timing belt is small and invisible, it controls the rhythm of the entire engine. Once it breaks, the consequences are disastrous. Replacing the timing belt is a complicated, time-consuming and labor-intensive process, but replacing it before it breaks can prevent engine damage and may be the best investment you can make to save an engine overhaul!

FAQ

1. What should I do if the timing belt breaks?

Stop the engine immediately and do not try to start it. Depending on the model, the problem may be valve jams or piston and cylinder head damage, requiring major repairs.

2. How much does it cost to replace a timing belt?

The labor cost for most timing belts is between 3-5 hours, and the total cost is between $400-1,000.

3. Can I replace the timing belt myself?

If you have a certain mechanical foundation, relevant tools and sufficient space, you can try; otherwise, it is recommended to be operated by a professional.