Worn Tensioners often create belt noise and drive people crazy trying to figure out where is the noise coming from.
Here is a trick you can use to isolate which pulley is making the noise: Get a Crayon, use reasonable common SAFETY (perhaps hold the crayon with a pair of pliers), and while the engine is running at an rpm = to when you hear the noise, ride the crayon on ribbed side until you get a consistent layer of wax on the belt, or until you hear a difference in the noise going away. I believe the tensioner (which I suspect is the problem) has a RIBBED pulley. So applying Crayon wax to the ribbed belt side offers some lubrication and the noise may go away. (Ever put grease on a squeaky hinge? Same concept.) If the noise continues, try waxing the flat side and see if there is a difference. I believe the idler pulley is flat, no ribs.
WARNING when waxing the flat side: Do this slowly and with extreme caution. Putting too much on can cause the belt to slip off the pulley(s) completely and you'll have a scary event when the belt pops off.
Either way, Wax the belt slowly (either ribbed side or flat side). Application of too much wax is counter-productive because then you'll be forced to purchase another belt. The idea is not to lubricate the belt permanently with a layer of wax. You simply want to logically eliminate pulleys by which side they are riding on the belt (flat or ribbed).
Use a bright color Crayon like yellow. This helps in you figuring out how much wax you've already applied.
If you are fortunate to have only applied a light coating of wax, the belt will be fine. The normal operating temperatures will eventually melt the wax and the belt will absorb the excess as it's distributed around the belt ride path.
Again, automatic tensioners are chronic for causing belt noise. They may look fine, but the slightest wear causing an offset at the pivot point will make belts cry and drivers to cringe.
Road Noise is often caused by tire tread wearing unevenly. Especially if the tire tread blocks have low and high areas. They may be hard to see, but examine the tread at the edges. If you see any deviations in the tread patterns as you spin the tire, or see high/low spots, this causes surprisingly amplified tire noise. The back tires typically grow uneven wear (high/low) in contrast to the front. Try rotating tires front to back / back to front.
Good luck.
Dec 17, 2008 at 11:14 PM
