What is the difference between a tensioner and tensioner pulley?

What is the difference between a tensioner and tensioner pulley?

My car has 90000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi, thanks for your question. For your 2009 Honda Odyssey, the tensioner and tensioner pulley are one unit. They make up what is called the tensioner assembly. This tensioner assembly has two pulleys located on it and they can be replaced separately.

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The primary distinction between tensioners and idler pulleys is the presence of an adjustable bolt. Tensioners are positioned on the bolt through mounting. Idler pulleys are not mounted to an adjustable bolt. However, the differences between idler pulleys and tensioners also extend to purpose.
A tensioner pulley uses a spring loaded arm or a hydraulic actuator to apply the proper pressure and help keep the belt tensioned and aligned. On a drive belt system, the tensioner pulley is spring loaded to maintain proper tension and alignment of the serpentine belt.
If the pulley is damaged, replace the tensioner assembly not just the pulley. If an idler pulley is damaged, inspect the tensioner also because vibrations caused by a bad idler pulley may damage the tensioner.
Tensioners can be divided into three general categories; fixed, adjustable, and automatic.
The main physical difference between an idler pulley and tensioner pulley is a simple adjustable bolt! However, in terms of function and purpose, an idler pulley is responsible for guiding a belt drive in an engine or mechanical system, while a tensioner pulley is responsible for tensioning the drive belt.
Most engines use one idler pulley, and one tensioner pulley, though some designs do use more than one idler. Over time, idler pulleys will eventually wear out and need to be replaced.
If the tensioner is loose the belts may squeak or squeal, especially when the engine is first started. It is also possible for the tensioner pulley or bearing to wear out, in which case the vehicle will produce a grinding noise from the pulley.
If your vehicle has a bad belt tensioner, you should not drive it. A bad belt tensioner is reason enough to perform some DIY mechanical work on your own or consult with an experienced mechanic for assistance.
Tensioners can be either static (fixed) or dynamic (moving) in operation. A static tensioner means that the tension is set and the tensioner fastened into place to keep that specific tension against the belt during drive system operation.
Most modern cars that roll off the dealer`s lot as a new vehicle will have a 60,000 to 100,000-mile life expectancy for the serpentine belt, tensioners, and idler pulleys.
Tensioning pulleys of the chains or a sliding block are attached to the lever with a screw. It is a universal flexible element that can simultaneously perform the functions of suspension, guidance, tensioning and damping.
Tensioners apply the correct amount of tension to the timing belt to ensure a synchronous drive. They play a vital role in the engine: if the tensioners fail, the engine can fail too. Tensioners allow the timing belt to move smoothly through the engine, powering various components.
The tension of an “ideal cord” that runs through an “ideal pulley” is the same on both sides of the pulley (and at all points along the cord).
Tensioner and idler bearing consists of basic components like inner ring, outer ring, retainer, grease and seal. Pulley may be added to adjust rotation ratio. Bracket may be added to adjust location for adding tension. Races are one of the bearing component parts.
The belt tensioner can be mechanic (spring-loaded) or hydraulic. A hydraulic tensioner is a better fit when a spring-loaded mechanical automatic tensioner cannot provide sufficient damping or tensioner movement. A hydraulic tensioner is practical for applications with high loads and/or angular vibrations.
The GEARWRENCH Serpentine Belt Tool is used to release the tension on the serpentine belt and self-adjusting idler pulley.
A good “Rule of Thumb,” seek approximately ½ Inch of deflection for a V-belt. To be more precise… The “Span Length” is the distance from where the belt is leaving one pulley, and is completely seated on the second. Seek 1/64 (0.015625) of an inch deflection for every 1 inch of belt span length.
Replacement: Replace the tensioner pulley if you notice any signs of wear, damage, or looseness. Don`t wait until the pulley fails, as this can cause other components to fail as well. Belt replacement: Replace the accessory belt and tensioner at the same time.
Place your pulley face down on a flat surface, then put your ruler or caliper on top, measure from outside edge to outside edge across the circle of the pulley. Check carefully to make sure you are measuring across the center.
– 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. Cracks on the under-sides of belts can lead to loose belts.
If the timing belt tensioner isn`t keeping the timing belt tight, the engine will go in and out of perfect timing. Some of the most common issues caused by tensioner failure include: Difficulty starting the engine. Sluggish acceleration.
Yes it can. However, it will not charge the battery, or move the water pump, or power steering pump, or even the AC compressor. So it will be a race to see what happens first, the engine overheating, or the battery dying.
You should expect to replace your belt tensioner in the 40,000-70,000 mile range. It is also customary to swap more than one part simultaneously, usually a worn-out pulley from other systems and even the serpentine belt itself.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

What is the difference between a tensioner and tensioner pulley?
ANSWER : Hi, thanks for your question. For your 2009 Honda Odyssey, the tensioner and tensioner pulley are one unit. They make up what is called the tensioner assembly. This tensioner assembly has two pulleys located on it and they can be replaced separately.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to perform an inspection and repair for you.

after replacing belt, idler pulley, and tensioner pulley tahoe still sqeaks in the morning?
ANSWER : At the next cold start, try this: Take a spray bottle with some water and spray the belt then start it. If you hear the noise, then the problem may not be with the belt or tensioner. If you do hear it, then it’s possible that one of the pulleys (a/c,water pump,etc) may be slightly glazed or out of round. It’s also possible that a bearing, such as in the water pump, alternator, or a/c compressor clutch may be the issue. Sometimes a bearing that is on it’s way to failure can squeal when cold until it warms up. Alternator bearings are a common source. A mechanics stethoscope may be a good tool to locate a squealing sound. Since the noise is primarily on a cold start, the vehicle may need to sit for several hours or even overnight to get the noise to occur and found with the stethoscope.

On the 4.7 which tensioner plate goes with which tensioner?
ANSWER : The best thing to do is look at the brackets that are to be mounted behind each tensioner and match up the bolt holes that mount the brackets in place. Then install the chains and install the tensioners. Then you can tighten them up. The brackets are different and if they are switched, the chains will not connect with the tensioners hooked up. So if the tensioners are able to hook up to the chains with the brackets on, then they are in the right location. If you need further assistance with your timing chain tensioners and brackets, then seek out a professional, such as one from Your Mechanic, to help you.

Serpentine belt is rubbing on the engine cover at the belt tensioner pulley 2004 Hyundai Tiburon
ANSWER : Hi there – I would start by doing a visual inspection of the serpentine belt, and the pulleys – are they visually in line? If not, which pulley is out of line in the direction of the engine cover? Are there bushings on the alternator mount which have softened, and are allowing the alternator to "give" such that the serpentine belt is close to the cover? The crankshaft pulley is not likely moving at all. Is the cover where the rubbing occurs coming loose, and moving into the serpentine belt? For assistance, I would recommend a serpentine belt replacement by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

crankshaft pulley turns, water pump belt doesn’t. It’s making a squealing noise.
ANSWER : Hi there. In this case, it’s likely that one of the pulley’s is frozen or the bearings inside the water pump are damaged which is the source of your problem. It’s typically a good idea to replace the water pump, belts and pulley’s to resolve this type of problem.

With engine off. Crankshaft pulley spins freely with belt on or off. 96 Taurus 3.0. What could cause that?
ANSWER : I can think of a few possible causes to this issue.
1. You are trying to replace the belt with a new one and may have got the wrong size belt. There are two different 3.0 V6 engines that are available for this vehicle so you may have got the belt for the other engine. The solution to this issue would be to swap the belt out at the parts store for the correct belt and try again.

The belt is the correct size but the belt tensioner is unable to hold tension against the belt causing a lack of traction between the belt and the pulleys. This would result in the pulleys not spinning fast enough to cause any of the belt driven assesories to work properly.
The crankshaft pulley bolt or woodruff key has broken causing the crankshaft pulley to be loose on the crankshaft. This can also cause a lack of tension on the belt causing the belt driven assessories not to work.

Just replaced both belts on 2008 Fx35 infiniti.
ANSWER : Hey Dan, thanks for inquiring. I don’t know that you necessarily need to replace your pulleys, neither tensioner or idler. However, if you are hearing a squeaking from your engine and suspect the pulleys are the problem then replace them as needed. I don’t think you really need to replace pulleys every time you replace the belts.

I have broken 3 sepentine belts in the last week, i replaced the tensioner pulley as well. What else could be causing my issue?
ANSWER : The pulley has a ball bearing within. The failure mode, or causes of failure, is limited to three possibilities: 1) defective, or worn out, ball bearings; 2) lubrication failure; 3) overloading. To eliminate possibility Nos. 1 and 2 you could try using the OEM Toyota supplied part. As far as overloading, measure belt tension to see if it is excessive. For example, a possibility is you have the wrong belt (too short) and that would increase the load on the bearing. Also, check to be sure that all the pulleys are operating in the same plane. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a serpentine belt/rotating elements diagnostic and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.