For many years, drive belts, V-belts, multi-vee-belts, and serpentine belts have been used to transmit power from the engine crankshaft pulley to add-ons, such as the power steering pump, air-con compressor, water pump, or cooling fans. Toothed timing belts and timing chains, too, are accustomed to transmit power from the crankshaft to the camshafts, plus some from the camshaft to camshaft, based on engine design.

The drive belt, timing belt, or timing chain won’t work well, or for lengthy, if, with incorrect tension. A loose drive belt won’t drive the item reliably, slipping and producing sound. Conversely, an excessively limited belt may cause accessory or pulley bearing harm. Various forms of tensioner pulley maintain long-term engine and item quietness and reliability.

Tightening or Loosening
Sometimes, maintenance or repair will demand tightening or loosening a tensioner pulley. Changing a drive belt or timing belt, for instance, would require you to loosen a tensioner pulley to make room for the brand new belt, as the new belt is smaller sized than the worn drive belt.

You’ll need to tighten a tensioner pulley, in most cases, after the installation of a new drive belt, or to adjust for a stretched drive belt that hasn’t worn enough to warrant replacement. Stretch out belts don’t require tensioner pulleys but are “stretched” into place using a special tool-always utilize the special tool to avoid belt damage.

Tensioner pulleys Car Pulley Belt generally fall into two types: accessory-integrated (AI) and non-accessory-integrated (NAI). Think about AI tensioners as adjustable add-ons, such as an alternator, and NAI tensioners as adjustable idler pulleys. There are three types of tensioner pulleys and several ways to loosen them.
Mechanical tensioner pulleys are the simplest, the majority of common, and least prone to failure. There is one caveat, however, as mechanical tensioner pulleys need manual adjustment. This makes them prone to user error, resulting in insufficient or excessive belt pressure. Additionally, they need to be adjusted to compensate for belt stretch as time passes.