Too many people find out the hard way that the most important maintenance item in your car is the engine timing belt. If the timing belt in your engine breaks, your car will stop running immediately or, worst case,your engine may be destroyed. That’s not an exaggeration, a broken timing belt can ruin an engine, perhaps beyond repair.
First, let’s look at what a timing belt is. The timing belt is a heavy-ribbed rubber belt deep in your engine that couples the crankshaft to camshaft(s). Essentially, it keeps the valves in the top half of the engine in sync with the pistons and crankshaft in the bottom half. This is a critical part of the engine’s operation.
Today, some cars and trucks have timing belts and some have metal timing chains. In theory, timing chains can last the life of the engine so you don’t usually have to worry about them too much. Rubber timing belts, however, wear out over time. They actually wear down and the rubber deteriorates. Eventually, a rubber timing belt will snap and the engine will stop running. So, how do you find out which you have: a belt or a chain? Well, you could consult your owner’s manual and see if timing belt maintenance is listed.Or, call your local dealer and ask their service department. It’s not a bad idea to know.
So if you have a car that does have a timing belt in it, should it be replaced? Auto and truck manufacturers have various schedules for timing belt replacement, but the rule of thumb is some 60,000 miles or so. Some vehicles are more, some as less.The problem with a used car with a lot of mileage on it is that you may not know when it was last replaced. Plenty of cars have 100,000 miles or more on their original timing belt and that’s a disaster waiting to happen. If you are in doubt as to how old your timing belt is, see your local dealer and have it examined. A mechanic can quickly judge a timing belt just by pulling a cover and looking at its condition.
As explained to us by the service manager at Kayser Ford of Madison, WI, a full service Ford dealer, if your timing belt breaks, it could destroy your engine.Here are the details. It depends if your engine is an “interference” or “non-interference” engine. An interference type engine means that the valve’s stroke and piston’s stroke physically overlapwithin the cylinder but at different times. The timing belt is timed so they don’thit each other. If the timing belt snaps, the valves will drive into the pistons causing bent valves or even cylinder head damage. Generally speaking, it’s a very expensive repair. In a non-interference engine, the pistons and valves don’t overlap, so if the timing belt breaks, no valve or cylinder damage occurs, the engine just stops running. The situation is far less critical if you have an older belt in a non-interference engine. If the belt snaps, the engine just stops running.
Generally speaking, a lot of work is involved when changing a timing belt so they can be expensive to fix. A typical job would be around $600 but with some engines, it can be much higher. If the belt in your car is over 80,000 miles or so, you should consider changing it just for peace of mind.