We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Harmonic Balancer?

By Lori Kilchermann
Updated Jan 26, 2024
Our promise to you
WikiMotors is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WikiMotors, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A harmonic balancer is a device that is mounted onto the crankshaft of an internal combustion engine. The harmonic balancer is a pulley-like device comprised of two cast-iron components coupled by a rubber ring. As the engine spins, harmonic vibrations from the valve train as well as the entire rotating assembly — which would otherwise destroy the engine's main bearings — are absorbed by the rubber ring and balanced by the outer iron part of the harmonic balancer. Most timing marks that are used to set ignition timing on a vehicle are also scribed onto the outside edge of the harmonic balancer.

In a passenger vehicle, the stock harmonic balancer is usually sufficient. It is designed to last the duration of the vehicle's engine, and in most applications, it does just that. Oil that may leak onto the balancer, however, can deteriorate the rubber inner component of the harmonic balancer and cause it to break loose. When this happens, the vehicle may run noticeably rough or not run at all. The trouble can be caused when manufacturers mount the ignition trigger on the harmonic balancer.

In a high-performance application, the stock design of the balancer will not sufficiently protect the engine. The high-speed operation of a racing engine would cause the balancer to separate at the rubber ring and thereby break the engine. Occasionally, a stock harmonic balancer would break and actually be thrown through the vehicle's hood. This was a very dangerous occurrence and led to stock balancers being prohibited for use in racing applications. Racing balancers are constructed of a solid steel outer shell and are filled with a thick viscous fluid inside to absorb the harmful vibration.

Unlike the stock units, racing type balancers are marked with a special date code and require replacement after a predetermined time period. It is up to the individual race-sanctioning bodies to set the replacement date and perform the safety inspections. When installing a high-performance balancer on an engine, it is typically suggested that a high tensile strength bolt be used to secure the unit to the engine's crankshaft. With only a single bolt affixing the balancer to the crankshaft, this is a wise rule of thumb to which to adhere. Many companies manufacture special high-strength bolts for this particular application, and a balancer bolt should never be reused once removed from an engine.

WikiMotors is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

WikiMotors, in your inbox

Our latest articles, guides, and more, delivered daily.

WikiMotors, in your inbox

Our latest articles, guides, and more, delivered daily.