Drive belt loosening on its own? 2007 Kia Rio

So basically in my car there’s 3 drive belts. The one that goes over the alternator I’ve been having issues with. It has broken twice and now I think it’s getting ready to break a third time. The second time it broke, after replacing I took my car to a mechanic to have it looked at because I really did not want to deal with this issue anymore, but now the belt is starting to squeal a lot like it was last time, and I checked the belt and noticed it’s gotten WAY loose. So maybe that’s been the issue all along is that the belts are just getting loose until flying off and breaking or something like that. Another thing worth noting is that sometimes when I first time my car the power steering seems ‘choppy’. Like not completely smooth steering wheel turning it’ll stop for brief moment in the turn. I’m not totally sure if this is just when the car has just started or just at low speeds in general.

Anyways I want to know what would be causing this, what I should look at, and how I can fix it.

I suggest you watch a YouTube video on replacing your alternator belt. Your problem could be several things. After adjusting the tension, are you locking down the mounting bolts? As far as you power steering, I assume it is a serpentine belt, It could be a worn out tensioner, or if you live where they use a lot of road salt, it could be a frozen tensioner because of corrosion. If the tendsioner is not free to take up the slack as a new belt wears in and stretches a little, that will cause a loose belt. Any time you are dealing with belt problems, make sure all the pulleys are in alignment and that all driven accessories turn smoothly by hand.

Make sure all the pulleys are in line with the crankshaft pulley. The crankshaft pulley can shift if the harmonic balancer is starting to fail which can cause the belts to fray, jump or break. Use a long straightedge. Also check the alternator and its bracket for cracks. And check any idler pulleys for rough bearings indicating imminent failure.


Are you buying the $8, $12, or the $25 belt?

You get what you pay for with these cars that only use 1/2" wide belts.

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It’s also possible you aren’t getting the correct part number for the replacement belt. If your car uses grooved accessory belts, make sure the number of grooves on the working surface of the belt matches the grooves in the pulley. When the belt is removed make sure all the other pulleys on that path move freely, silently, little to no sideways or axial play, and are not binding. Sometimes you can position yourself so you are viewing the belt path from the side. If so, make sure everyone on the path resides on the same plane.

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