When to Replace Car Engine Drive Belts: Auto Repair & Maintenance Tips

"Hi! I’m William Myers from Austin Subaru for Expert Village. Okay why should you know anything about your alternator or AC belt? Let’s say you turn your AC on and it makes this loud, horrendous squeaking sound, it’ll sound like someone stepping on a cat it’ll be horrible, it’ll make this loud sound if you turn the AC off the noise goes away, the belt maybe too loose, okay there maybe other problems but it could just be a belt issue. Like a lot of the complains are I’m going down the highway and all the sudden I hear this loud screech and then it goes away, well if the AC belt gets loose the compressor cycles on and off as part as its job and if the belt was loose when the compressor locks up to reengage that compressor and the belts a little loose that belt is going to slip on the pulley and its going to make a loud noise. Like on your alternator and power stirring belt if you’re turning the stirring wheel and you heard a loud screeching noise and it went away as soon as stopped turning the stirring wheel, the odds are your alternator power stirring belts loose that’s the reason why you kind of want to know this stuff, plus if you’re going on a trip you’ll want look at them, notice if there were any cracks in them, if there were any cracks then you’ll probably want to take it to a care facility and have somebody else, I think I need my alternator belt replaced. There’s a lot of things that for knowing just little things that can help you in the long run, so when somebody comes to you and say well you need an alternator belt replaced, well why it’s not squealing, it’s not screeching can you show me…they say well they run their hand on it and they pull off of this black stuff that doesn’t necessarily mean the belts bad, usually a belts bad when you see lots of cracks in it. Alright this is what a drive belt looks like off a car and as you can see if you flip it inside out you have these channels right here and this is where the cracks will form when a drive belt starts to go bad, you’ll have lots of little hair line cracks on all these ridges and when you see those cracks that’s when you know it’s time to replace your drive belt. This drive belt happens to be in good shape, that’s a drive belt."