For decades, drive belts, V-belts, multi-vee-belts, and serpentine belts have already been used to Car Pulley Belt 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 used 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 won’t work well, or for lengthy, if at all, with incorrect tension. A loose drive belt won’t drive the item reliably, slipping and producing noise. Conversely, an excessively restricted belt may cause accessory or pulley bearing harm. Various types 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. Replacing a drive belt or timing belt, for example, would require you to loosen a tensioner pulley to make room for the brand new belt, as the new belt is smaller sized compared to the worn drive belt.

You will have to tighten a tensioner pulley, generally, after the installing a new drive belt, or even to modify 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 use the special tool to avoid belt damage.

Tensioner pulleys generally fall into two classes: accessory-integrated (AI) and non-accessory-integrated (NAI). Think of AI tensioners as adjustable add-ons, such as for example an alternator, and NAI tensioners as adjustable idler pulleys. There are three types of tensioner pulleys and many methods to loosen them.
Mechanical tensioner pulleys are the simplest, most common, and least susceptible to failure. There is certainly one caveat, however, as mechanical tensioner pulleys need manual adjustment. This makes them prone to user error, leading to insufficient or excessive belt pressure. Additionally, they have to be adjusted to pay for belt stretch over time.