Car Doctor Q&A: Smart Daughter With a Noisy Belt

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A friend of ours once said “You can’t give a haircut over the phone,” commenting on how hard it is to provide good diagnostics remotely. But that’s what this dad did with his daughter, and they got their issue about 90 percent solved. Car Doc John Paul gets them the rest of the way home.

Q: My daughter called me (she lives about 150 miles from home) and said that her car was making a loud squealing belt sound. After some telephone diagnostics we felt it was the main drive belt and a worn belt tensioner.

Well, my talented daughter removed the belt and the belt tensioner and replaced them with new parts. All was great for about a week and now the noise is back.

Any ideas where to go from here?

A: The first thing I would do is look at the belt to see if she didn’t line up the belt on the pulleys. If the belt is riding off of one of the pulleys even by one rib, it could have been enough to wear the belt and cause it to make noise.

The other possibility is one of the pulleys is out of alignment with the others. This will cause belt noise and increased belt wear. The pulley alignment issue happens often enough where some belt manufacturers have come up with a laser belt/pulley alignment tool.

If she needed to remove a component and left out a spacer and the pulleys are not lined up exactly, it could be enough to cause the belt to make noise.