The timing belt on your vehicle may seem insignificant. After all, most people don’t think about replacing this belt until their car stalls in the middle of city traffic or a busy freeway. Some vehicle owners may never have even heard of a timing belt before. What is it exactly and what is it’s purpose? Let’s take a closer look and try to answer some of these questions. This notched synthetic rubber belt is reinforced with fiber cords. It is responsible for coordinating the operation of the crankshaft and camshaft in internal combustion engines. Most have “teeth” on their inner surface that match the gears of the engine.
The timing belt sustains the vital precision for an engine’s operation. It harmonizes the camshaft and crankshaft rotations, allowing pistons and valves to move in sync. It turns the camshaft, which opens and closes intake and exhaust valves. Intake valves send oxygen and fuel mixture into your engine for combustion. Exhaust valves permit waste products to be eradicated from the cylinder once the oxygen and fuel mixture have burned.
The timing belt assumes the role of keeping the engine “in time” mechanically. The top and bottom half of a four-stroke, internal combustion engine must be absolutely in sync with its bottom half to finish a four-stroke cycle of intake, compression, power, and exhaust. The belt interacts with various cogs that connect to the crankshaft or bottom half of the engine and the camshaft or top half of engine. The timing belt achieves absolute agreement by synchronizing each movement of the top and bottom halves of your engine to effect the four-stroke cycle that generates power in your engine.
A vehicle’s timing belt can go bad in an instant. It is a polar opposite of other car parts that go gently into the good night. Whether the belt breaks or a couple of teeth strip your car will grind to a standstill. There are all sorts of scenarios imaginable, but “worst case” is when valves and pistons impel themselves into the camshaft and get badly bent or broken. As is true with most mechanical things, prevention is the best cure, especially for parts such as this one that get a constant workout. Take the time on a regular basis to inspect the belt. Look closely for missing teeth, cracks, discoloration, or fraying. If you’re not comfortable under the hood, take your vehicle to a professional auto mechanic. Signs of a worn out belt aren’t reliable enough to postpone regular maintenance. You might hear a high pitched noise, like whirring, when the timing belt begins to wear. You might also have trouble starting your vehicle.
If a vehicle has what is known as an interference engine, valves are in the direct pathway of pistons. Experts suggest that if the crankshaft or camshaft moves autonomously in an interference engine, a valve versus piston collision is bound to happen at least once. Delicate valves will bend and you can expect a pricey repair. If your vehicle has a non-interference engine, a timing belt breakage is annoying but not financially devastating. Just have a tow truck bring it to your auto repair shop for replacement. Your engine won’t be compromised. The moral of the story is, if your vehicle has an interference engine, it’s critical to make sure the timing belt is in good shape. As a general rule, timing belt replacement occurs between 60,000-100,000 miles. Be sure to check the owner’s manual for manufacturer recommendations.