Squeaky alternator pulley. This kind of noise may or...
Squeaky alternator pulley. This kind of noise may originate from your fan belt, alternator pulley, or from the modern serpentine belt, so you will have to figure out which one is the perpetrator. [6] so recently I started hearing a squeaking sound coming from the belt/pulley area and it definitely sounds like it's coming from the alt pulley. You may sometimes still hear it even after you have turned off the alternator pulley and car engine. Left unattended, the problem that causes a pulley squeal will likely become worse and lead to expensive alternator or engine repairs. Oil wetted iron is less prone to corrosion. This squealing noise is mostly caused by a bad serpentine belt. The serpentine belt in your car powers the accessories such as air conditioning, power steering, the alternator, and waterpump. Jan 7, 2026 · The most frequent cause of alternator squeaking is insufficient tension on the serpentine belt. Essentially, it keeps many vital systems in your car running smoothly. This video shows how to diagnose alternator pulley noise, check belt tension, inspect the bearing, and replace the faulty pulley before it damages the alternator. When dirt and heat accumulate around the alternator, it causes the bearings to fail and make a noise. Make sure the grooves in the belt align with the grooves in ALL the pulleys. If it is ok, then check the belt for any traps, wear, cracks - if found then replace. The bearings work is to rotate the rotor that produces electrical power in a vehicle. Pulley wear will cause your pulley to squeak. Watch the Video! New alternator on, still squeaks, now I have to put the factory belt, tensioner, and idler pulley back on so they can try again… Dang - this was my squeal at 65k miles. I've changed the tensioner pulleys and the belt is new but the noise is still there How Does a Bad Alternator Bearing Sound Like? Bad alternator bearings make a squeaky and grinding noise. Hello. If the noise persists, then check the alternator pulley and its distance from it's centre shaft as the change in angle of belt will create the noise and it will recreate if the belt is replaced. Master the diagnostic steps to identify the noise source and choose the correct repair, whether external or internal. A good way to tell if it's the alternator pulley specifically is to listen for whether or not your automobile wails even before you touch the steering wheel. I`d posted earlier in the week about a squeaky tensioner pulley. Nov 8, 2025 · This article explains what the pulley does, the clearest symptoms, quick driveway checks, professional diagnostics, repair options, and safety considerations so you can distinguish a bad pulley from a bad alternator or belt problem. Can I Put WD 40 On A Squeaky Belt? WD-40 can silence the noise if your car squeaks when AC is on. Is your car making a squealing noise? It might be a noisy idler pulley. its an irritating wuuuuuuuuuhuuuuuuu sound but it goes away after about 7mins on idle. A squealing alternator pulley is not only annoying, it indicates a problem with the car's belts or alternator. If your car’s alternator belt is making a squeaking noise, this is often because there is not enough tension in the belt, causing it to slip on the pulleys. Hearing strange sounds from your alternator? This comprehensive guide identifies, diagnoses, and addresses common alternator noise issues. When it does, it may slip on one or two of the pulleys, which will cause a squeaking noise. This squeaking would typically get louder as the engine reaches higher revolutions per minute (RPM)sign that an alternator is going bad. This can happen due to stretching or a faulty tensioner. Its main function is to transfer rotational energy from the engine to the alternator, allowing it to generate electricity for your vehicle’s electrical systems and to recharge the car battery. When a belt slips out of the car’s pulleys due to a bad tensioner or from a case of belt misalignment not checked, it will create friction with other drive pulleys and squeal. On other sites, many folks detail replacing pulleys and belts, on squeaking issues on this engine, and then still having noise problems. You have to run engine at least twice per months to ensure any appearing rust wears off. So, why does the serpentine belt squeal on cold start? If you have a worn-out or defective tensioner, it will influence the tension level of the belt on the system’s pulleys. In addition, it helps to safeguard other parts from premature failures and undue stress, such as the car alternator and water pump. I was wondering if anyone has experienced a squeak/chirp on these 5. could I by chance spray something to stop it or would I screw up the belt? What is an alternator pulley? The alternator pulley is mounted on the front of the alternator and connected via a belt to the crankshaft. A worn out pulley bearing or a worn spring in the tension pulley can also cause squeaking. ” My question is, can I just put WD-40 on the bearings on each pulley to find the squeaky one, or is this not a good idea? Typical things that cause a belt to squeal are pulley misalignment, improper belt installation, or contaminants such as belt dressing or coolant. Learn how to reduce belt drive system vibrations with specialized alternator pulleys that improve engine efficiency and increase the life of the belt tensioner. Displacement of the alternator and Crankshaft pulleys is also part of the reason why the alternator belt does make a noise when driving, and the only solution to this issue is by making sure of aligning the pulleys along a single guide. could I by chance spray something to stop it or would I screw up the belt? Take the belt off and start the car and see if it goes away. Old cars do not have a tensioner but rather use an adjustment with the alternator mount. That sounds like a bearing squeak not a belt squeak, so your culprit is most likely one of the idler pulleys or an alternator or compressor The clearance between stator and rotor inside alternator is almost nil. It's responsible for powering essential components such as the alternator, air conditioner compressor, power steering pump, and more. If the squeaking noise persists, the serpentine belt is the cause of the squeaking noise. I took the serpentine belt off and spun all the accessory wheels. If this internal clutch fails, it can cause the belt to ride improperly or introduce excessive vibration, which may manifest as a squeal or chirp. 0 First, check the belt tension, then check the tensioner for wear. Learn how to spot signs of a bad car alternator and get free alternator testing plus expert guidance at O’Reilly Auto Parts to keep your vehicle running smoothly. The sound of a squeaky belt in your vehicle’s engine is usually because the rubber belt is slipping on the metal pulley. Listen Carefully: Try to pinpoint which pulley the squeal is coming from. Spraying WD40 on pulleys of the drive belt will temporarily stop the squeal, but it won’t solve the issue and will further harm it. You may also check whic When these pulleys or your drive belt goes bad, it generates squeaky noise. When you turn your key to the ON position for a few seconds, the computer will realize it doesn’t need the alternator to produce so much electricity. I checked the belt and there are no cracks or marking i also replaced the idler pulley while that helped there is still squeak after that i spun the Silverado without the belt on and the one an the alternator gave a squeaking noise it doesn't sound like the alternator is bad to me and really would rather not replace it Any advice or ideas???? When your belt is loose or failing sometimes it can’t turn the alternator pulley, so it’ll slip producing the squeaky noise. Tips on fixing the fault. Oct 27, 2016 · If the chirp is actually coming from the belt, it will be right at the alternator pulley, which could easily be mistaken for sounding like it's coming from the bearing. If the alternator isn’t running correctly (or running at all), the pulley on the component may slip or stick and cause the whining noise you’re hearing when you drive. Squeaking Sounds – a squeaking sign is often a sure sign that your alternator is faulty. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. It only is present when engine is cold then goes completely away when engine is warmed up after driving it. Do it only when you intend to replace it after that. If the sound goes away, the noise comes from one of the pulleys. I go to the Ford dealer and they are telling me it is the alternator and quoted me a ridiculous amount to re-replace the alternator and they said there is no way it’s the water pump after they did a “sound test. The tensioner and idler pulleys, which are essentially support bearings for the belt, are frequent sources of squeaking and chirping that can be easily confused with an alternator noise. So, is there a way to tell if I need a new alternator or just a decoupler pulley? From what little I gather, a bad Decoupler Pulley makes a rattling sound, NOT a squeak. Hear an awful squealing noise coming from your serpentine belt? In this video, we show you how to diagnose and fix a squeaky serpentine belt in just a few ea The serpentine belt is a long, winding belt that runs through a series of pulleys in your engine. The alternator sounds is inconsistent, even gravelly but I don't think a squeak sound carries over the broomstick. So, let’s figure out the possible causes of the squeaking noise and how to fix the problems. It isn't obvious that it is the PVC gasket; here is how I The tensioner and idler pulleys, which are essentially support bearings for the belt, are frequent sources of squeaking and chirping that can be easily confused with an alternator noise. Loosen the mount, pull on the pulley or alternator till the belt is very taught and then tighten the bolts with the alternator in place. I replaced that,and still the squeak. Learn how to fix a squeaky alternator bearing before it gets out of hand. I used to have the noise even in the summer when started but i replaced the idler pulley and put on If you hear a squeaking, squealing or an irritating noise coming from your vehicle, the noise may have originated from your fan belt, alternator pulley, or from the modern serpentine belt thus you have to identify where the noise really came from. I show you how to use water to identify what type of squeak problem you have and then how to find the The reasons why the alternator belt may squeal are a bad belt tensioner, inadequate belt replacement, a problem with one of the idler or drive pulleys, belt or pulley misalignment, and a bad belt. Build up of rust bridges the gap seizing alternator. To check the idler pulley bearing remove the serpentine belt and spin the pulley by hand while listening for a bearing squeak or squeal letting you know the idler pulley bearing has gone bad and needs to be replaced to fix the problem. Pulley misalignment, where the alternator pulley sits slightly off-axis from the other accessory drive pulleys, can also cause the belt to wear unevenly and produce noise. It`s not wobbly,etc,and Typical things that cause a belt to squeal are pulley misalignment, improper belt installation, or contaminants such as belt dressing or coolant. This will cause different levels of pressure, and it can develop a glazed look and feel. Turns out the ALTERNATOR is squeaking! I spin it by hand and yep,that`s what`s making the noise. You May have the Wrong Size Belt A squealing alternator pulley is not only annoying, it indicates a problem with the car's belts or alternator. Grab a spray bottle and spray water on the rotating belt. so recently I started hearing a squeaking sound coming from the belt/pulley area and it definitely sounds like it's coming from the alt pulley. How do you fix a squeaky alternator noise? If that is not the culprit, examine the compressor clutch and pulley. Check Tension: Use a belt tension gauge (or the deflection method, detailed later) to ensure the belt is within the manufacturer’s specifications. Watch the Video! Displacement of the alternator and Crankshaft pulleys is also part of the reason why the alternator belt does make a noise when driving, and the only solution to this issue is by making sure of aligning the pulleys along a single guide. i get a funny noise on the pulley, alternator and tensioner areas of my e46 320i when i start it once it has cooled down. Explore symptoms, causes, and solutions to address this common issue. Fix your squeaky alternator fast. A noisy alternator can be a sign of a bigger issue. Misalignment The serpentine belt can slip from misalignment. 3 afm motors. DIY car repair with Scotty Kilmer, an auto mechanic for the last 50 years. Feb 12, 2026 · Why the alternator belt squeals: diagnosing contamination, tension, pulley misalignment and bearing wear. #alternator I have a squeaking coming from my serpentine belt area I’ve replaced the belt,alternator,tensioner pulley the tensioner itself is relatively new ac compressor is less than a year old water pump aswell anyone have any ideas of what it could be? K24 btw I have a squeaking coming from my serpentine belt area I’ve replaced the belt,alternator,tensioner pulley the tensioner itself is relatively new ac compressor is less than a year old water pump aswell anyone have any ideas of what it could be? A worn out pulley bearing or a worn spring in the tension pulley can also cause squeaking. If you hear a squealing or whirring noise in front of your car, whether the belt noise goes away when warm or not, it could be so annoying and embarrassing. Idler pulley squeak? Learn how to fix a squeaky pulley in your car. If the clutch is wobbling or the pulley teeth are bent or damaged, replace it. However, in some cases, the fluid might weaken and break down your car’s serpentine belt. . How I quickly and effectively pinpoint a noisy bearing, pulley, alternator, water pump,ac compressor, belt tensioner or idler pulley on any vehicle. Alternator issues The alternator is responsible for converting mechanical power into electrical power to keep the engine running and battery charged. If the belt is too loose, the friction between the belt material and the alternator pulley decreases, causing the belt to slip, particularly under heavy electrical load or during engine startup. THIS IS THE BEST AND VERY AFFORDABLE SCAN TOOL. The serpentine belt in your car powers the accessories such as air conditioning, power steering, the There is an adjustment bolt on the tensioner that allows you to increase the tension. Why Is The Belt Squealing? Learn how to fix a squeaky tensioner pulley in your car. Spray wicking oil into the windings from pulley side but do not overdo the treatment. Similar to when your tires squeal on the pavement, this slip causes a dreadful noise. The belt could have some wear on the grooves of the ribbed side, or the edges may be worn. 0vjcp, c9lca, 1svq, uaiz, 3etxlg, fyw9d, xsdhz, 7ojqd, xv7bm, lbmxj8,