Belts came off

While driving, I detected the smell of something burning. I stopped and opened the hood and noticed two belts unraveled, one broken, the other still intact, just off the pulleys.
Experienced mechanics share their insights in answering this question :
Your vehicle uses two serpentine belts: one for the accessories and one for the A/C. I have known the A/C belt tensioners to fail on these vehicles, causing damage to the belt. There is also a technical service bulletin (TSB) for pulley alignment issues which could cause your problem as well. The number of that TSB is 01-02-32-007, and it takes power steering pump pulley alignment may be the issue. A failed water pump, or any other belt driven component, could also cause your belt to shred apart. I suggest you have a trained professional inspect and repair your vehicle and replace your serpentine belt if necessary.

How to Identify and Fix Common car Problems ?

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If your serpentine belt keeps coming off, it`s likely due to one of three issues: the tensioner is loose, the pulleys are misaligned, or the belt is worn out. If the tensioner is loose, you`ll need to tighten it. If the pulleys are misaligned, you`ll need to realign them.
What are the dangers of driving with a broken alternator belt? If you continue to drive with a broken alternator belt, you run the risk of loosening your engine`s cooling systems, which can result in the engine overheating—this can lead to severe engine damage and, in some cases, total engine failure.
A loose drive belt will often be noisy, squeaking a bit, or emitting a high-pitched squeal. The most obvious sign of a loose drive belt, though, is in its appearance and tension. A loose belt, simply stated, looks and feels loose.
Because the serpentine belt is responsible for so many critical systems, make sure it is kept in good working order, along with the belt pulleys and tensioner. Sometimes the belt falls off (rather than breaking) because the pulleys and tensioner are worn, damaged, or misaligned.
If your serpentine belt is failing, you may notice performance issues with your vehicle. The vehicle may frequently overheat. Your air conditioning or power steering may fail to work or not work properly. You may notice your vehicle battery failing to recharge if the alternator is affected by a bad serpentine belt.
If you ever hear growling or whining noises coming from under the hood, you could have alternator problems, which should be checked out by a professional ASAP. This growling or whining sound happens when the belt that turns the alternator`s pulley becomes misaligned or rubs against the side of the pulley.
If the belt breaks while you are on the road, the car will break down immediately – and your engine can experience severe damage. You need to look out for signs and symptoms of a weakening timing belt so that you can take action before it is too late.
As these belts wear out, they can begin to squeak or squeal. They make noise because there is not enough tension on the belt, or because the pulleys are misaligned or weak. Often, simply changing the belt will make it stop squealing. The noise isn`t usually a danger, though it does sound alarming.
If the serpentine belt completely fails and breaks, then your car will break down. In addition, you will notice a loss of power steering, the air conditioning will not work, and the engine will no longer be able to be cooled like it should be.
If the belt is too loose, the power steering will not be as responsive. If the belt is too tight, the steering will be difficult. If you hear strange noises coming from the front of your vehicle or the power steering belt looks worn, you may need your power steering belt replaced by a trained professional.
If the dampener is not able to control the tensioner arm, it can cause fluctuations in tension. The belt may oscillate between too little tension and too much tension. The belt will slip and catch, causing noise and vibration.
There are a couple of factors influencing the answer to this question, but on average, your car should be able to run between 20-90 minutes with a broken serpentine belt. The engine will overheat faster without a functioning cooling system on a hot day, so your driving window is less.
Since the serpentine belt helps provide power to cool the engine, a faulty belt can cause the car engine to overheat as the water pump will not turn. As soon as the engine begins to overheat, have it inspected by a mechanic as it can cause a breakdown and cause engine damage if left overheated.
– Belts A belt slipping around a pulley reduces the efficiency of the components it drives. A worn, defective, or incorrectly tensioned belt can lead to battery failure and engine overheating.
What happens when alternator stops working while driving? The car tends to slowly lose power if the alternator has gone bad while the car is being driven. You`ll notice the headlights start to dim shortly before the car loses power and dies.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

hey i had a belt break while traveling on my 2004 honda pilot. It is the small belt and not the serpentine belt. The mechanic t
ANSWER : Hello. The smaller belt is known as your timing belt, and it works inside the engine to keep mechanical components aligned with each other during the compression cycle. The serpentine belt, which is the big belt, drives the alternator, water pump, AC compressor, and a couple of other components. If the small belt broke it is likely the timing belt. This will cause the car to stall, lights to illuminate, and can even cause serious damage to the engine. Typically replacing a timing belt is a lot more complicated and expensive than replacing a serpentine belt. You may want to receive a second opinion on the car before you go ahead with repairs.

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Timing belt is tight and yet appears to be slipping several teeth when belt is rotated,
ANSWER : This is okay since there are more notches on the belt than the amount on the sprockets. Once you aligned the first time the belt marks will almost never line up perfectly again. The marks are used to put the belt on correctly. They aren’t used as an indicator after the engine is turned again. You should be okay to start the motor as long as timing marks on pulleys line up. If you run into any issues, have a certified technician, like one from YourMechanic, assist you with the replacement of the timing belt.

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Can you change the defected water pump without changing its defected belt (which is the drive belt and only belt in this model of
ANSWER : Hello. Yes you can replace the water pump without replacing the serpentine belt. If the belt is worn, and it breaks while you are driving, you can damage a lot of other components in that area. Typically the price of a serpentine belt is relatively inexpensive. You will have to remove the belt to replace the water pump anyway. Since you are likely going to have to purchase a new pump, we do recommend that you purchase a belt at the same time. You SHOULD replace the belt if it is worn, and this is a perfect time to do it. It is not necessarily required, but you are putting yourself at risk of another break down at a later time. Not to mention if the belt is already worn, manipulating off and back onto the vehicle while changing the water pump can further damage it, and shorten the amount of time its got left. Belts should be replaced before they break, as to the amount of damage they can cause when they do break. Again, you may be able to get away with not replacing the belt right now, but if its as worn as you say, its going to break sooner than later and should be replaced.

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Belts are cracked and need replacing, okay to leave off a/c belt?
ANSWER : Hello. If the belt driving the A/C compressor only drives the A/C compressor and nothing else, you can remove it with no consequences. The fan shroud is not optional equipment however as it has both a cooling system function and a safety function.

Depending on your climate, you might consider diagnosing the A/C system and repairing it. If you use a service such as YourMechanic, it will often be economical enough to do it, particularly if the fault is limited.

Even if the compressor shaft sealing is leaking (would be likely after 25 years), that is fixable in the field. Feel free to contact YourMechanic if you have additional needs relative to this or the replacement of your power steering, alternator, A/C belts.

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Timing Belt Cover replacement and External Belt too.
ANSWER : The parts are touching likely because either the parts were not installed properly or fasteners may be missing or broken. If oil has been leaking, this can cause the seal around the covers to swell as well causing misalignment. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer inspection of the belt drive to see what is causing the misalignment and offer a more personal diagnosis as well as estimate the proper repairs.

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Old belt was sqeeking, new belt does not but it slips off constantley. The old belt stays on though. Why is this?
ANSWER : Check to be sure that the new belt is actually the right part number or, better yet, use an OEM (dealer) belt. Also, be sure the tensioner is the right part number or use an OEM sourced tensioner. Check to be sure that all of the pulleys and accessories (e.g., alternator, water pump, A/C compressor) that are driven by the serpentine belt are all operating in the same plane. It is not unusual for the pulley on the crankshaft harmonic balancer pulley to move (generally outward) relative to its original position. The pulley is rubber bonded and over time can move. If that pulley moves, that means that the belt groves are no longer running in a perfect plane and that alone can cause slipping. If you request serpentine belt inspection a certified Mechanic, dispatched by YourMechanic right to your location, will identify the problem and thence get the issue resolved for you promptly. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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Serpentine belt tearing apart by pebble & pieces of it getting inside timing belt, motor destroyed
ANSWER : Hi there. I agree with you – this doesn’t pass the ’smell test’. The only way for debris to enter the engine is through the throttle body. Since the throttle body inlet is protected and covered by an air intake on your Ford Fiesta, I highly doubt that this is the source of your problems.

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belt is missing, squeeling sound before stopped engine, once stopped saw smoke coming from engine department
ANSWER : Hi there:

In cases like then when you’re not sure what component needs to be replaced, it’s always best to have one of our professional mobile mechanics complete a car is hard to start inspection first. This will allow the mechanic to review your car for damage that is causing the symptoms you’re experiencing and then recommend the right replacement or repairs be completed to resolve your issue.

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