Both the water pump and timing belt are important when it comes to engine maintenance. So, while you’re going through the difficulty of replacing the water pump, save some time and labor costs by replacing the timing belt at the same time.
Water pump life
Water pumps are supposed to last for 100,000 miles or more, and they rarely die suddenly. Usually over time, the water pump will begin to leak from the wear and tear of thousands of miles of use. While you can usually drive with a leaky water pump, it is generally a good idea to replace it as soon as possible.
Most water pumps are not particularly expensive, but getting access to them can be difficult and replacement can be time-consuming. In most vehicles the water pump is located towards the front of the engine. To reach the water pump you either have to remove engine components and work in a small space to remove the pump. Either way this is a time-consuming and potentially difficult process.
Replacing the timing belt
Replacing the timing belt is one of the more important jobs for engine maintenance. Most modern engines use this toothed belt to synchronize valve opening with piston position. When this belt breaks, the results are potentially disastrous. A broken timing belt can result in extensive and expensive engine damage.
To avoid this issue, vehicle manufacturers recommend changing the timing belt at regular intervals. These vary by engine, but 90,000 miles is a typical recommendation. Consult your owner’s manual to verify the belt change duration for your car. As with the water pump, timing belt replacement can be a big job, especially on a transverse engine, simply because it's in such tight confines.
When replacing the timing belt it makes sense to replace the water pump and any other associated components - drive belts, timing belt idler pulleys, tensioners and tensioner pulleys - as well. While you may be able to get an additional 10,000 miles or so out of the associated components after the timing belt needs to be replaced, replacing these with the timing belt can reduce labor costs when you need to dive back in and replace any of these components in the future. Furthermore, it's always a good idea to be proactive with the maintenance of your car, for a water pump and timing belt are a lot cheaper than a new engine.