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 components, like 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, and some from the camshaft to camshaft, depending on engine design.
The drive belt, timing belt, or timing chain will not work very well, or for very long, if at all, with incorrect tension. A loose drive belt won’t drive the accessory reliably, slipping and making sound. Conversely, an excessively restricted belt may cause item or pulley bearing harm. Various kinds of tensioner pulley preserve long-term engine and item quietness and reliability.
Tightening or Loosening
Sometimes, maintenance or restoration will demand tightening or loosening a tensioner pulley. Changing a drive belt or timing belt, for example, would need you to loosen a tensioner pulley to create room for the brand new belt, as the new belt is smaller than the worn drive belt.
You will have to tighten a tensioner pulley, generally, after the installation of a new drive belt, or to adjust for a stretched drive belt that hasn’t worn enough to warrant replacement. Extend 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 generally fall into two groups: 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 ways to loosen them.
Mechanical tensioner pulleys will be the simplest, most common, and least prone to failure. There is definitely one caveat, nevertheless, as mechanical tensioner pulleys require manual adjustment. This makes them prone to user error, leading to insufficient or extreme belt stress. Additionally, they need to be adjusted to compensate for belt stretch over time.