Fairly easy to detect before it happens and expensive to repair, a timing belt breakdown won’t just ruin your day, it could wreck your engine. Your owner’s manual explains when the belt should be replaced, but there are also telltale signs when a timing belt is ready to go. Here’s what you need to know about this important under-the-hood component.
Timing belt fundamentals
The timing belt is a small, narrow belt that connects the engine’s crankshaft to the camshaft, controlling when the valves open and close. It’s located outside the engine and is generally visible except where hidden by an engine cover. In some vehicles, it also wraps around the water pump, controlling its operation as well. When a timing belt fails, you’re not going anywhere.
In some engine designs, known as interference engines, a broken belt can cause the valves and pistons to collide, damaging your engine. On the other hand, in a non-interference engine, the pistons do not travel into the areas where the valves open. Thus, when the belt snaps, the engine will soon come to a halt without damaging key components.
Determining which type of engine is in your car is important, although that information isn’t always readily available. You can Google to find out if your vehicle has an interference or noninterference engine.
It’s also important to note that some vehicles have a timing chain instead of a belt. The chain is located inside the engine and lubricated by the same. They’re designed to last longer than belts. In fact, they often last as long as the life of your car, truck, van or SUV.
Signs of wear & tear
Fortunately, timing belt breakdown usually doesn’t just happen. At least not without some type of warning.
The warning signs typically begin with a ticking noise coming from the engine. This is usually an indication of low oil pressure or the engine isn’t properly lubricated. If you hear squealing when accelerating, braking or idling, the belt may be ready to go. If the engine fails to turn over, overheats or you notice motor oil puddling underneath your vehicle, then the belt may have already failed.
There are also visible signs that your timing belt is ready to break. Cracking on the top or bottom of the belt indicates excessive wear. Material loss, which means a chunk or more of the belt is missing, is another important indicator. Further, glazing underneath the belt means the belt is stiff and no longer able to supply the required flexibility. Sometimes other components, such as the pulley or tensioner have failed. If so, the timing belt will no longer work.
Replace your timing belt
Most timing belts must be replaced between 70,000 and 100,000 miles as per your owner’s manual. Familiarize yourself with all maintenance due items and have these tasks accomplished within the manufacturer’s recommended range. Indeed, if something does go wrong and you’re following the manufacturer’s guidelines, your costs may be covered under the manufacturer’s standard or extended warranties. Otherwise, all costs, including parts, labor and repairs are your responsibility.
Replacing a timing belt typically includes also replacing the water pump as the labor costs involved make it sensible to replace both at once. You’ll pay several hundred dollars for the parts and labor, but that cost is only a fraction of what you might pay if the belt breaks and destroys the engine.
Consider belt replacement as your self-insurance for avoiding a catastrophic and financially debilitating repair bill along with extended time without the use of your vehicle. Add in the cost of renting another vehicle and your costs will be exacerbated further.