When should I replace my timing belt?
The timing belt is one of those parts that must be replaced sooner, according to the vehicle manufacturer’s schedule. In most cases, this is every 75,000 to 100,000 miles. Consult your owner’s manual for your vehicle’s exact schedule.
Replacing your timing belt is not something you can put off forever. At some point the belt will break and you could end up with thousands of dollars worth of engine damage. It’s not worth the risk.
Timing Belt Replacement Instructions
Unless you have extensive experience repairing cars, replacing a timing belt is not an easy DIY job and should be done by a professional.
The mechanic will need to remove various accessories to access the engine’s timing cover. After removing the cover, the mechanic will analyze the timing belt and its pulleys to determine what needs to be replaced. At this point, I’d begin removing the timing belt and replacing it with a new one. I’d also plan to replace the pulleys, tensioner, and water pump if I felt it was important.
Once all the new parts are installed, I’d reinstall the timing cover and any other parts I removed. Now that everything’s back together, I can start and test the engine.
Is the engine running properly? Is the engine control OK? If the answer to both questions is yes, you are on the right track. Just pay the mechanic and you’re done.
How the timing belt works
Unless you drive an electric car, all modern cars are equipped with a timing belt or timing chain. Learn more about timing chains here. The timing belt serves to synchronize the rotation of the crankshaft and camshaft. This precise timing ensures that the engine’s valves open and close at the correct intervals relative to the position of the pistons, allowing for the proper intake of air and fuel and the exhaust of burnt gases.
The belt is usually made of reinforced rubber and has teeth that mesh with sprockets on the crankshaft and camshaft. When the crankshaft rotates due to the forces of combustion, the timing belt rotates, which in turn rotates the camshaft at exactly half the speed of the crankshaft.
Motors are classified as interference and non-interference motors, and the type of motor has a significant effect on the tolerance of the timing belt.
In an interference engine, the pistons and valves occupy the same space in the cylinder at different times. If a timing belt breaks, the pistons can strike the open valves and cause serious (and expensive) damage to the engine.
An engine without interference has enough clearance between the pistons and the valves even if the timing is out of sync. If the timing belt breaks, the engine will still stop, but it is less likely to cause catastrophic damage.