New Timing Belt, possible bad water pump

[Steven Cummings]

Hi All,

About 4500 miles ago I replaced the timing belt/water pump in our 3.5L Chrysler engine. There is a “whirring” noise coming from the timing belt chamber that appears to be centered at the water pump (with the stethoscope it’s barely audible by the cam sprockets or idler). It doesn’t appear to have become any louder over the time I’ve installed it, but it shouldn’t be there either since it wasn’t on the old pump. Could this noise just be the side-effect of aftermarket (NAPA-new), or something I should try to get replaced while under warranty (ugh, don’t really want to get back in that engine)

Also, if I replace the water pump, should I replace the timing belt (i.e. 4500 miles used of the 100K service interval) or is the new one acceptable. I had an uncle saying that it will break if taken off and put back on (not sure I completely believe this, but can be convinced)

Topic

[Pat61]

Play around with your stethoscope and see if you can pinpoint the noise exactly. It could wind up being noise generated by the new belt (sounds kinda like a moderately loaded alternator)

As for the timing belt, I doubt taking it off and putting it right back on will harm anything lest you pinch/kink it. However, if you didn’t put new idlers on with the new water pump, I would think twice about saving the belt.

[Bill]

The number 1 cause of a whirring sound after a timing belt replacement is having the belt tension set too tight. I, myself, have very good luck with Napa water pumps and they don’t usually make the sound you describe anyway.

You can usually remove and install a used belt as long as it was not kinked or damaged in some way and it is installed in the same direction of rotation.

[Joe]

it could be something like a timing belt idler pulley too. I would think that the best thing to do now is to at least get to the belt and look at it. A stethascope or a long screwdriver would be pretty good for trying to pinpoint exactly where the noise is coming from.

[Lorrin Barth]

Too tight will make a noisy belt. But even when tensioned correctly and using an OEM belt you get a different sound than before.

[Author]

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