If there’s one constant when it comes to the downside of letting car maintenance slip – well, at least from a folklore standpoint! – it’s that your timing belt is going to break at 90,000 or 100,000 miles and catastrophic engine damage may occur.
Is it possible? Sure. However, there are several not so often discussed aspects of the timing belt and its function that, once covered, will help you view this aspect of car maintenance objectively and with calm.
First of all, you may not even have a timing belt. Although you likely do, some cars have a timing Chain, which is much stronger than a rubber belt. Timing chains typically never need replacing. If your vehicle does have a timing chain, You are dismissed for the day! (And be sure to check back next week for a new blog subject!!)
…Okay, now that we are exclusively among belt owners, let’s delve deeper into timing belt function and maintenance:
While the timing belt doesn’t have quite the glamour or name recognition of the valve and the piston – which are usually what pop to mind when you think of a car engine in action – the timing belt is really what holds the whole system together. It keeps the valves and pistons moving and in sync with each other.
While today’s timing belts are made of heat resistance rubber, they still wear over time…and then, of course eventually will break. Your first line of defense (As usual!) is to consult your owner’s manual for the recommended interval for timing belt replacement. Typical mileage runs are 90,000 – 105,000 before a belt needs replacement. Of course, your mechanic will want to be checking the belt periodically for a healthy amount of time before reaching your recommended replacement mileage.
Next, if for some reason proper periodic inspections do not keep you from experiencing a broken timing belt…You still have some chance of avoiding serious damage; to be exact, you have a 30% chance of being fine. That’s because 30% of engines on the road are “free-running”, or “free-wheeling”, engines. In such engines, the designers have purposely built in enough clearance space between internal parts to prevent damage in the event of timing belt failure.
So, you 30%-ers are also (kinda) dismissed, although, really, you probably should remain for the rest of our discussion. Your best bet still, of course, is to keep up with inspections and appropriate placement of your timing belt.
However, for the 70%-ers, your engine is what’s called an “interference” engine. Simply put, these engines do not have built-in clearance space between parts. When a timing belt breaks in this type of engine, parts begin moving out of sync, and continue to move until they collide with other parts they shouldn’t be colliding with. Bent valves, broken pistons – these are a couple of the possible complications when an engine continues to run out of sync.
So that gives you a quick idea of what timings belt do…and also what a broken timing belt can do. Your best bet? Avoid living out the part where those not-meant-to-be engine parts are colliding with each other. Find yourself a good mechanic, let them check your timing belt periodically well before the recommended replacement interval and, when that is all taken care of…Go find yourself another car system to worry about!