My serpentine belt has weird “bubbling” on 90% of the right side of it

2000 Toyota Corolla LE

I bought my car used last year and the last owner said he replaced the serpentine belt. The whole top of the belt (right side only) has a weird bubbling effect. It’s not really bubbling, it just looks like there is thicker spots of rubber. Very odd. I took the belt off and the bottom is perfectly fine. No cracking or anything.

Should I replace the belt? And Why did this happen? I’ve noticed it since I bought it

I am going on a 600 mile road trip in a week


Since you know how to take it off and replace it just get a new one and be done with it. You can’t tell how good that belt is just by looking at it .

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I probably should’ve changed it but I didn’t have a belt on me at the time. I mainly just don’t want it to happen again to the new belt so I’m trying to find out what caused this or if anyone has ever seen it before

I’d replace it, I’d also check out any idler pulleys that press on the ‘top’ of the belt, one might be misaligned or have a bearing going out.

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Texas beat me to it. Make sure all pulleys are aligned correctly. Check the belt tensioner for correct operation. And replace the belt.

You’ll want to bring the old belt on your trip just as a backup if needed.

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+1 to Volvo’s comment, but I want to add that the OP may have a mis-aligned pulley, so it is entirely possible that similar damage will happen to the replacement belt. If that happens, then it is time to check into the reason for the mis-alginment.

Edited to add that Texases beat me to it!

Is checking for misalignment as easy as just looking for it? So if I see a misaligned pulley, I would be “bent” in a way?

I’d check that the pulley spins smoothly, and that it shows even wear across the surface that presses on the belt. If anything is the slightest bit off, I’d replace it.

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After you change it, take that old one, wrap it up like the new one was, place it in a plastic bag and put it in your trunk. If you are ever out late at night or on the road and the new one breaks, you have an emergency replacement.

While driving cross-country several years ago, I had one fail not far from a service center/rest stop. I limped in and the service center did not have a replacement, and told me that it would be “tomorrow” before I could get one. I told them, luckily I have the old one and they begrudgingly installed it and I was on my way. The next day I stopped at a parts store and installed a new one myself…

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Find and repair the oil leak before putting on a new belt.

Tester

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The OP is going on a trip in a week, so that might not be an option. I’d rather see a new belt thrown on now under those circumstances.

Where did I type,“Before the trip”?

Tester

The belt in the pictures looks very dry, and if you look harder (zoom in) you can see the belt is starting to do the same thing on the outer side as well as already doing it on the inner side… Just looks like a really old belt… Just change it, and it is always a good idea to check all your pulleys for wear and play anytime the belt is off…

This makes sense. My valve cover gasket was leaking like crazy before. A couple months ago I installed a new one and it’s as dry as can be. I installed a new belt and so far see no accumulation

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