What does the tension pulley do?
A drive belt tensioner is a pulley mounted on a spring system or adjustable pivot point that is utilized to keep tension on the engine belts. … Both are used to keeptension on the engine serpentine belts so that they can travel the various engine accessories.
How do you adjust a tensioner pulley?
Switch the adjustment bolt on the side, top or bottom level of the pulley counterclockwise with the ratchet and socket until the equipment belt is loose enough to remove. Tighten the tensioner pulley by turning the adjustment bolt clockwise with the ratchet and socket before belt is tight.
How do you know
A tensioner pulley manuals the belt around the tensioner and allows the belt to spin while the tensioner maintains pressure against it. A failing tensioner pulley could cause power loss 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 heat. Pulleys are usually manufactured from either plastic or steel, so verify the pulley itself for just about any damage as well. At O’Reilly Automobile Parts, we have tensioner pulleys available for many vehicle models.
The computerized pulley tensioner has an internal spring-loaded mechanism that keeps the serpentine belt under regular tension. Its design enables it to keep carefully the serpentine belt taut, in order that the other accessory pulleys rotate at the same rpm (revolutions each and every minute) while under the same secure pressure. Tensioner pulleys may also absorb mild shock loads that happen when the air conditioning unit cuts on / off. As a constantly rotating aspect, the pulley tensioner can provide off some warning signs before failure.
Rust and Corrosion
The pulley tensioner sits exposed to the elements at the front end of the engine. Put through puddled water “splash-up,” as time passes the tensioner arm and pulley device can rust. Rust can freeze the automatic tensioner device or corrode the shaft bearings, that may cause a frozen posture in the adjustment pressure. Without the correct stress, the belt can slide.
Rocks, gravel and other road debris can be thrown up in to the tensioner pulley grooves and jam the mechanism. This can allow the serpentine belt to slip on the tensioner pulley and melt away. Overheated pulley temperatures results, and finally the serpentine belt will melt and snap off.
Pulley Tensioner Spring
The pulley tensioner spring in the housing can become weak from age and repeated exposure to heat. This causes the belt to flutter and skip instead of maintaining a constant strain on the pulley. Symptoms of a fragile spring show as glazing on the lower of the serpentine belt, with an intermittent flickering of the dashboard’s charging light indicator. Squealing or squeaking will always be read at the belt site.
If the tensioner pulley wobbles on its shaft, it means the interior shaft bearings have worn. This may cause a pulley misalignment. Bad bearings cause an audible growling noises. The outer ends of the serpentine belt will fray and stretch out the belt. Ultimately the rubberized belt grooves flatten out and cause key slippage. An excessively wobbling pulley can toss the belt off, creating all the accessories to quit functioning.
Lever Arm Freeplay
Some tensioner pulleys possess markings on the housing 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.
The tensioner pulley face must match 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 equipment pulley, can measure the angle. Any off-angle measurement indicates worn shaft bearings in the pulley casing.
Serpentine Belt Noise
A moderately worn serpentine belt gives off a constant squeaking sound during engine idle. Belts which have worn severely job a loud chirping or squealing appear. The cause tips to a glazed, donned or cracked belt. Dried out or partially frozen tensioner pulley bearings could cause such sounds by deteriorating the belt prematurely.
Lever Arm Oscillation
A lever arm that repeatedly oscillates back and forth during idle or more speeds means the the within damper mechanism in the tensioner pulley has weakened or broken. This causes sporadic tension strain on the belt and can manifest itself with intermittent chirping sounds.