Mar 08

Do it Yourself Serpentine Belt Replacement

Do it Yourself Serpentine Belt Replacement

This belt, obviously past its prime, ran for 115,000 miles/184,000 kms, and it was still within the tension limits specified. It’s toast, regardless.

There’s a squeal emanating from underneath your hood—and it doesn’t sound good. The noise started a few months ago, on a gray and rainy morning, but it went away before you even pulled out of the driveway. Problem solved, right? Sorry pal. Unfortunately, the noise was back the very next morning, and this time it lasted all the way to the corner of your block. You lifted the hood and zoomed in on the offending racket—it was the serpentine belt. As the weeks dragged on, your morning commute got noisier and noisier every day. Then you began to hear it on the way home too. Now it’s a constant reminder to replace the belt. Soon.

Most modern cars don’t use old-fashioned V-belts anymore. In the ’70s, as more and more cars were optioned with lots of power-hungry accessories running off the crankshaft pulley, it often became necessary to have as many as four V-belts, each running a different gizmo. There just isn’t room for that many belts and pulleys anymore—not to mention, this belt configuration means that it’s a service nightmare to replace just the inner belt by itself. You’d have to remove the other three first—not a fun job.

There are several advantages to the new style of serpentine belts. A single belt, winding its way through a forest of pulleys, can now drive every single engine accessory at the same time. A single belt only an inch or so wide saves 3 or 4 in. of engine room real estate. Better still: Most of the serpentine-belt installations use a spring-loaded tensioner pulley that keeps a constant preload on the belt, eliminating the need to adjust the tension. If you’ve ever needed three hands and a tire iron to pry an alternator away from the block while simultaneously tightening the adjustment bolt-and-nut combo, you’ll appreciate what a giant leap forward that is.

There’s one last, very compelling advantage to serpentine belts: They don’t wear out, at least not for a really long time. A fresh belt will probably last 150,000 miles/240,000 kms without any maintenance at all. Contrast that with the expected 40,000- to 50,000-mile/ 64,000- to 80,000 kms life span of a heavily loaded V-belt.

{ excerpt from http://www.popularmechanics.com/cars/how-to/maintenance/4311197 }