What does the tension pulley do?
A drive belt tensioner is a pulley mounted on a spring mechanism or adjustable pivot point that is utilized to keep tension on the engine belts. … Both are being used to keeptension on the engine serpentine belts to ensure that they can travel the various engine accessories.
How do you adapt a tensioner pulley?
Flip the adjustment bolt privately, top or bottom level of the pulley counterclockwise with the ratchet and socket before item belt is loose enough to remove. Tighten the tensioner pulley by turning the adjustment bolt clockwise with the ratchet and socket until the belt is tight.
How do I know
A tensioner pulley manuals the belt around the tensioner and allows the belt to spin as the tensioner maintains pressure against it. A failing tensioner pulley could cause power damage and damage to your belt-driven systems. You might have a failing tensioner pulley if you hear any squeaking or squealing beneath the hood. Bearings on the pulley can wear out, causing noise and temperature. Pulleys are usually made of either plastic or metal, so examine the pulley itself for just about any damage aswell. At O’Reilly Auto Parts, we have tensioner pulleys available for many vehicle models.
The automatic pulley tensioner has an internal spring-loaded mechanism that keeps the serpentine belt under frequent tension. Its design permits it to keep carefully the serpentine belt taut, to ensure that the other equipment pulleys rotate at the same rpm (revolutions each and every minute) while beneath the same safe pressure. Tensioner pulleys can also absorb gentle shock loads that happen when the air conditioning unit cuts on / off. As a regularly rotating component, the pulley tensioner can give off some indicators before failure.
Rust and Corrosion
The pulley tensioner sits exposed to the elements at the front of the engine. Put through puddled water “splash-up,” with time the tensioner arm and pulley system can rust. Rust can freeze the automatic 
tensioner device or rot the shaft bearings, that may cause a frozen position in the adjustment pressure. Without the correct stress, the belt can slip.
Debris Contamination
Rocks, gravel and other highway debris can be thrown up in to the tensioner pulley grooves and jam the device. This can allow the serpentine belt to slip on the tensioner pulley and burn. Overheated pulley heat range results, and eventually the serpentine belt will melt and snap off.
Pulley Tensioner Spring
The pulley tensioner spring inside the housing may become weak from age and repeated exposure to heat. This triggers the belt to flutter and skip rather than maintaining a constant strain on the pulley. Symptoms of a fragile spring present as glazing on the underside of the serpentine belt, with an intermittent flickering of the dashboard’s charging mild indicator. Squealing or squeaking will always be listened to at the belt site.
Pulley Wobble
If the tensioner pulley wobbles on its shaft, it means the inside shaft bearings have worn. This will cause a pulley misalignment. Awful bearings trigger an audible growling noises. The external ends of the serpentine belt will fray and stretch the belt. At some point the rubber belt grooves flatten out and cause significant slippage. An excessively wobbling pulley can throw the belt off, causing all the accessories to quit functioning.
Lever Arm Freeplay
Some tensioner pulleys possess markings on the casing that indicate the utmost range that the pulley can travel. If the lever arm of the tensioner rides under or over the designated mark, it indicates a stretched belt or a lever arm that has jammed in a single position.
Pulley Misaligment
The tensioner pulley face must match up to the other accessory pulleys with a parallel alignment. Placing an extended, straightedge ruler against the facial skin of the tensioner pulley, and then flushing it against another accessory pulley, can measure the angle. Any off-angle measurement indicates worn shaft bearings in the pulley casing.
Serpentine Belt Noise
A moderately donned serpentine belt gives off a constant squeaking sound during engine idle. Belts that have worn severely job a loud chirping or squealing audio. The cause tips to a glazed, donned or cracked belt. Dry or partially frozen tensioner pulley bearings can cause such noises by wearing out the belt prematurely.
Lever Arm Oscillation
A lever arm that repeatedly oscillates back and forth during idle or more speeds means the the inside damper mechanism in the tensioner pulley has weakened or broken. This causes sporadic tension pressure on the belt and can manifest itself with intermittent chirping sounds.