What does the tension pulley do?
A travel belt tensioner is a pulley mounted on a spring mechanism or adjustable pivot point that is employed to keep tension on the engine belts. … Both are used to keeptension on the engine serpentine belts to ensure that they can drive the many engine accessories.
How do you change a tensioner pulley?
Transform the adjustment bolt privately, top or bottom level of the pulley counterclockwise with the ratchet and socket before equipment 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 you know
A tensioner pulley courses 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 reduction and damage to your belt-driven devices. You could 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 warmth. Pulleys are usually made of either plastic or metallic, so examine the pulley itself for just about any damage aswell. At O’Reilly Vehicle Parts, we have tensioner pulleys available for many vehicle models.
The programmed pulley tensioner comes with an internal spring-loaded mechanism that keeps the serpentine belt under continuous tension. Its design enables it to keep carefully the serpentine belt taut, to ensure that the other item pulleys rotate at the same rpm (revolutions per minute) while beneath the same safe pressure. Tensioner pulleys can also absorb mild shock loads that happen when the air conditioner cuts on and off. As a frequently rotating part, the pulley tensioner can give off some indicators before failure.
Rust and Corrosion
The pulley tensioner sits subjected to the elements at the front end of the engine. Put through puddled water “splash-up,” with time the tensioner arm and pulley system can rust. Corrosion can freeze the automatic tensioner device or corrode the shaft bearings, that will cause a frozen placement in the adjustment pressure. Without the correct tension, the belt can slide.
Debris Contamination
Rocks, gravel and other highway debris could be thrown up in to the tensioner pulley grooves and jam the system. This can permit the serpentine belt to slide on the tensioner pulley and burn off. 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 can become weak from age and repeated exposure to heat. This triggers the belt to flutter and skip rather than maintaining a constant pressure on the pulley. Symptoms of a weak spring display as glazing on the lower of the serpentine belt, with an occasional flickering of the dashboard’s charging lumination indicator. Squealing or squeaking will become listened to at the belt location.
Pulley Wobble
If the tensioner pulley wobbles on its shaft, it means the inside shaft bearings have worn. This will cause a pulley misalignment. Undesirable 
bearings trigger an audible growling noises. The external ends of the serpentine belt will fray and stretch out the belt. Sooner or later the rubber belt grooves flatten out and trigger main slippage. An excessively wobbling pulley can toss the belt off, leading to all the gadgets 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 higher 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 to the other accessory pulleys with a parallel alignment. Placing a long, straightedge ruler against the facial skin of the tensioner pulley, and flushing it against another accessory pulley, can gauge the angle. Any off-position measurement indicates donned shaft bearings in the pulley casing.
Serpentine Belt Noise
A moderately put on serpentine belt produces a constant squeaking sound during engine idle. Belts which may have worn severely job a loud chirping or squealing audio. The cause tips to a glazed, put on or cracked belt. Dried out or partially frozen tensioner pulley bearings can cause such sounds by deteriorating the belt prematurely.
Lever Arm Oscillation
A lever arm that repeatedly oscillates backwards and forwards during idle or higher speeds means the the inside damper mechanism in the tensioner pulley has weakened or broken. This causes sporadic tension strain on the belt and will manifest itself with intermittent chirping noises.