Replacing the waterpump and/or timing belt idler pulley

Replacing the waterpump and/or timing belt idler pulley at the same time as replacing the timing belt is totally up to the customer.

I will explain why we always check these items when replacing a timing belt, and why often replacing them pro-actively is a good idea.

First of all, many engines today are interference engines. That means, if for any reason, the timing belt breaks, tears or strips a tooth, the internal engine parts will contact each other and cause internal engine damage (i.e., the pistons will hit the valves).

The timing belt is routed (or runs) over a number of pulleys including the waterpump, timing belt tensioner, idler pulley, camshafts and crankshaft. These pulleys all run on bearings. If one of these bearings gets rough, or seizes, or if the waterpump develops a leak, it can break the timing belt.

Since the tension on these bearings will change between the current timing belt and the new timing belt, even if a bearing is not totally bad now, or even if the waterpump is not leaking now, there is a good possibility that they will after the belt is replaced.

Whenever we replace a timing belt, we are always careful to check the bearings in these pulleys for roughness. The same is true of the waterpump: we always check it for roughness and for leakage.

Many manufacturers will recommend pro-active waterpump replacement as good insurance whenever performing a timing belt replacement, particularly since the pump is readily accessible with the timing belt removed. Ultimately, though, it is the customer's decision.

Our main concern is that the customer is properly informed.

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