For decades, drive belts, V-belts, multi-vee-belts, and serpentine belts have been used to transmit power from the engine crankshaft pulley to add-ons, like the power steering pump, air conditioning 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 will not work well, or for lengthy, if at all, with incorrect tension. A loose drive belt won’t drive the accessory reliably, slipping and producing sound. Conversely, an excessively limited belt may cause item or pulley bearing harm. Various types of tensioner pulley keep long-term engine and accessory quietness and reliability.

Tightening or Loosening
Sometimes, maintenance or restoration will require tightening or loosening a tensioner pulley. Replacing a drive belt or timing belt, for example, would need you to loosen a tensioner pulley to make room for the new belt, as the new belt is smaller sized than the worn drive belt.

You will have to tighten a tensioner pulley, generally, after the installation of a new drive belt, or even to modify for a stretched drive belt that hasn’t worn enough to warrant replacement. Stretch belts don’t require tensioner pulleys but are “stretched” into place utilizing a special tool-always use the special tool to prevent 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 accessories, such as an alternator, and NAI tensioners as adjustable idler pulleys. There are three types of tensioner pulleys and several methods to loosen them.
Mechanical tensioner pulleys will be the simplest, the majority of common, and least prone to failure. There can be one caveat, nevertheless, as mechanical tensioner pulleys need manual adjustment. This makes them prone to user error, leading to insufficient or extreme belt pressure. Additionally, they need to be adjusted to pay for belt stretch over time.