What does the strain polea do?
A drive belt tensioner is a pulley mounted on a spring device or adjustable pivot point that can be used 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 adjust a tensioner pulley?
Turn the adjustment bolt on the side, top or bottom level of the pulley counterclockwise with the ratchet and socket until the accessory 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 can cause power damage and harm to your belt-driven devices. 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 high temperature. Pulleys are usually manufactured from either plastic or metallic, so examine the pulley itself for any damage as well. At O’Reilly Automobile Parts, we’ve tensioner pulleys available for many vehicle models.
The automated pulley tensioner has an internal spring-loaded mechanism that keeps the serpentine belt under continuous tension. Its 
design allows it to keep the serpentine belt taut, in order that the other item pulleys rotate at the same rpm (revolutions per minute) while under the same secure pressure. Tensioner pulleys may also absorb mild shock loads that happen when the air conditioner cuts on / off. As a constantly rotating component, the pulley tensioner can give off some warning signs before failure.
Rust and Corrosion
The pulley tensioner sits subjected to the elements at the front of the engine. Subjected to puddled water “splash-up,” with time the tensioner arm and pulley system can rust. Rust can freeze the computerized tensioner device or corrode the shaft bearings, that may cause a frozen job in the adjustment pressure. Without the proper tension, the belt can slide.
Debris Contamination
Rocks, gravel and other street debris could be thrown up in to the tensioner pulley grooves and jam the device. This can permit the serpentine belt to slide on the tensioner pulley and burn up. Overheated pulley temp results, and eventually the serpentine belt will melt and snap off.
Pulley Tensioner Spring
The pulley tensioner spring within the housing can become weak from age and repeated contact with heat. This triggers the belt to flutter and skip rather than maintaining a constant strain on the pulley. Symptoms of a weak spring display as glazing on the underside of the serpentine belt, with an intermittent flickering of the dashboard’s charging mild indicator. Squealing or squeaking will end up being heard at the belt position.
Pulley Wobble
If the tensioner pulley wobbles on its shaft, this means the inside shaft bearings have worn. This will cause a pulley misalignment. Awful bearings trigger an audible growling sound. The outer ends of the serpentine belt will fray and stretch out the belt. Ultimately the rubber belt grooves flatten out and trigger significant slippage. An excessively wobbling pulley can toss the belt off, creating all the equipment to quit functioning.
Lever Arm Freeplay
Some tensioner pulleys have markings on the casing that indicate the utmost selection that the pulley can travel. If the lever arm of the tensioner rides under or over the designated mark, this implies 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 a long, straightedge ruler against the face of the tensioner pulley, and then flushing it against another item pulley, can measure the angle. Any off-angle measurement indicates worn shaft bearings in the pulley housing.
Serpentine Belt Noise
A moderately donned serpentine belt produces a constant squeaking noise during engine idle. Belts that have worn severely job a loud chirping or squealing sound. The cause details to a glazed, put on or cracked belt. Dry or partially frozen tensioner pulley bearings could cause such noises by wearing out the belt prematurely.
Lever Arm Oscillation
A lever arm that repeatedly oscillates back and forth during idle or higher speeds means the the within damper mechanism in the tensioner pulley has weakened or broken. This triggers sporadic tension strain on the belt and will manifest itself with intermittent chirping sounds.
