How Does a Timing Belt Work?

The timing belt is a belt made of rubber that keeps your camshaft and your crankshaft synchronized so that your valve timing is always right. Some vehicles have a timing chain instead of a belt, but it serves the same purpose. If your valve timing is off, your engine won’t run properly. In fact, it may not run at all. The belt also regulates the power steering and the water pump.

If you have timing belt problems, your mechanic can identify the trouble and will probably recommend that it be replaced.

How the timing belt works

In the four-stroke engine, there are four strokes, or phases. They are:

  • The intake stroke: The piston moves downward, and the intake valve opens to allow the mixture of air and fuel to enter the cylinder. At this stage, the exhaust valve remains closed.

  • The compression stroke: The piston moves up and compresses the fuel and air mixture. All valves are closed.

  • The combustion stroke: The piston moves down, allowing the spark plug to ignite the fuel and air mixture, delivering power to the vehicle. All valves are closed.

  • The exhaust stroke: The exhaust valve opens, allowing excess fuel and air to leave the engine. The intake valve is closed.

While all this is going on, the timing belt works to turn the camshaft pulley (some vehicles have two camshaft pulleys) in conjunction with the crankshaft pulley. A bad timing belt can cause the camshaft and crankshaft to be out of synchronization, and this can be catastrophic for the car’s engine. It throws the valve timing off, and you can end up with bent valves, bent piston rods, or completely destroyed pistons.

You may notice problems in time. Timing belt noise can be a red flag – it usually sounds like squeaking in the belt, or rattling if you have a timing chain. A timing belt problem should never be ignored, so watch for signs that there could be something wrong. The last thing you want is to have to rebuild your engine. As a general rule of thumb, you should plan on replacing the belt every 60,000 to 90,000 miles, or at least have it checked.

For this reason, your manufacturer will have recommendations as to how often your timing belt should be replaced. Generally, around the 80,000 mile mark it is prudent to get a mechanic to replace your timing belt to ensure that the engine continues to run efficiently.


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Recent Timing Belt Replacement reviews

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1,156
42
6
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25

Jonathan

35 years of experience
424 reviews
Jonathan
35 years of experience
Chrysler LeBaron - Timing Belt - Brooksville, Florida
Jonathon, Is a Nice Guy with Patience and did a Great Job! Showed up on time and got the repairs done, I will only book him again in the Future, after I had an issue with another Business locally, I decided to give your mechanic a try, I am glad I did.
Honda Accord - Timing Belt - New Port Richey, Florida
A true professional. Extremely knowledgable friendly and efficient. Would not hesitate to use again. Thanks

Brian

23 years of experience
487 reviews
Brian
23 years of experience
Acura TL - Timing Belt - Jacksonville, Florida
Brian is awesome. This is the second time he’s come work on my car and I am extremely impressed. Recommend to everyone!
Kia Soul - Timing Belt - Jacksonville, Florida
The mechanic arrived a few minutes early, he was very cordial, professional, and knowledgeable. Work was performed in a timely manner he seemed to really know what he was doing. I would definitely have him work on my car again whenever I need something done that I am unable to do myself.

Eddie

40 years of experience
28 reviews
Eddie
40 years of experience
Honda Civic - Timing Belt Replacement - Star, Idaho
Eddie knows what he's talking about. He's gone above and beyond what is expected oh him. He didn't wash his hands off of my vehicle when it was giving him the greatest grief. He persevered through in getting my timing belt replaced.
Subaru Forester - Timing Belt - Meridian, Idaho
Upstanding job, Excellent service. Mr Eddie is very Efficient, friendly and professional . Highly recommended.

Victor

35 years of experience
160 reviews
Victor
35 years of experience
Honda Odyssey - Timing Belt - Albuquerque, New Mexico
He stayed beyond the appointment time to make sure my car was running they way it should. Friendly and professional.
Toyota Sienna - Timing Belt - Albuquerque, New Mexico
Victor arrived on time and finished the job ! Great service, I just made another appointment with him!

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