What does a idler pulley do?

  • Supports the drive belt to maintain proper tension
  • Reduces vibration and noise in the engine system
  • Prevents belt slipping or misalignment
  • Helps to extend the life of the drive belt
  • Keeps the engine components running smoothly

What happens when an idler pulley goes bad?

  • Causes squeaking or chirping noises from the engine
  • Results in excessive wear on the drive belt
  • May lead to engine overheating due to belt slippage
  • Can cause loss of power steering or air conditioning
  • Potential for the drive belt to break

Does idler pulley need to be replaced?

  • If there are signs of wear or damage
  • During regular maintenance intervals
  • When the pulley is noisy or vibrating excessively
  • After a certain number of miles driven
  • When replacing other engine components

Advantages of idler pulleys:

  • Enhance engine performance
  • Reduce maintenance costs
  • Ensure proper engine function
  • Improve overall vehicle reliability
  • Extend the life of drive belts

tension pulley

Process of Compound Pulley:


Creating a mold for the idler pulley design.


Pouring molten metal into the mold to form the pulley shape.

Raw materials:

Using high-quality materials for durability and performance.


Manufacturing the pulley according to specifications.

tension pulley


Quality control testing to ensure reliability.

Antirust treatment:

Coating the pulley to prevent rust and corrosion.

Separate inspection:

Individual inspection of each pulley for quality assurance.


Labeling the pulley with relevant information.

spa pulley

What is the function of the tensioner and idler pulley?

  • Maintain proper tension on the drive belt
  • Reduce wear and tear on the belt and engine components
  • Ensure smooth operation of engine accessories
  • Prevent belt slippage or misalignment
  • Support the drive belt in various operating conditions

How to stop a idler pulley from squeaking:

  • Regular lubrication of the pulley bearings
  • Check for any misalignment or damage
  • Replace the pulley if necessary
  • Adjust the tension on the drive belt
  • Inspect other engine components for issues

About HZPT

Founded in 2006, HZPT is a transmission components manufacturer dedicated to precision and speed, headquartered in Hangzhou. We specialize in producing various precision parts and complex products tailored to your needs. Before establishing an overseas sales team, we began producing 3D printer accessories, anti-theft screws and nuts, camera mounts, and more. In addition, we offer assembly production services to save time and costs. We strive to provide the highest quality, most competitive parts, and best service for projects of all sizes. Join us early, and we will help you spend wisely!

V Pulley