Engine timing belts have been around for many years, and as time has past, materials used to make the belts has improved greatly. In the early days of timing belts, replacement intervals were about every 30,000 miles. Today, the interval is much longer - between 90K and 100K miles. That's all good news for your pocket book!
Timing Belts
Many timing belts not only connect the camshaft(s) to the crankshaft, but also drive the water pump. At North Hills we've learned from experience that it is often a good idea to replace the water pump at the same time as the timing belt, because removal of the timing belt provides easy access to the water pump. If the water pump were not replaced at the same time and it later failed, the labor to replace the pump would be as much as replacing the belt.
"It just makes good sense to replace the water pump while the tech is already right there. The price of the water pump increases the total cost of work only slightly, but the benefit to our customers is significant."
Timing Chains
Many engines today have timing chains, not belts. Timing chains are not replaced at any particular mileage interval; instead, they are serviced on an as-needed basis.
Interference and Non-Interference Engines
If your engine has a timing chain, it's important to know whether you have an interference or non-interference engine. An interference engine is a type of 4-stroke piston engine in which one or more valves in the fully open position extends into an area that the piston may travel into. If the chain or belt should break in an interference engine, it is likely the engine will be ruined. In a non-interference engine, this risk does not exist because there are no valves moving about in the same space as pistons. Don't know whether your engine has a chain or a belt? Interference or non-interference engine? Feel free to ask one of our service managers. If your engine is interference, it may be a good idea to replace the timing belt now rather than put it off and have to buy a whole new engine later.
