5 Symptoms Of A Bad Crankshaft Pulley (& Replacement Cost)

It can be hard to identify the problem with an engine because there are so many parts. That’s the case when you have a bad crankshaft pulley or a bad crankshaft harmonic balancer. 

This article will discuss what signs to look for in a crankshaft pulley that is not functioning properly, its location, how it functions, and what the replacement cost might be. Here’s a quick overview of the signs to look for:

Engine vibrations and an irregular idle are the most obvious signs of a damaged crankshaft pulley. If you're unlucky, it could also lead to a damaged alternator or power steering pump.

Below is a list that explains the signs and symptoms of a bad crankshaft pullingey.

Bad Crankshaft Harmonic Balancer Symptoms

1. Engine Vibration

Engine vibration is the most obvious sign that there is something wrong with your crankshaft pulley. If you pay attention, this will likely be your first clue. 

A harmonic balancer is usually fitted to the crankshaft pulley. The harmonic balancer absorbs engine vibrations, which allows you to accelerate easily. Vibrations can be absorbed if the balancer is damaged. 

The defect results in noticeable shaking, which gets more severe the further you travel. 

2. Irregular Engine Idle

You will soon become familiar with the sounds of idle as you park your car. If something is not right, it may be due to the crankshaft pulley. 

A bad crankshaft pulley can cause irregular engine RPMs. This is because the dampener has to be under greater pressure when it's idling. It is possible that your engine RPMs vary from one place to another. 

3. Dead Alternator

The alternator is charged by the battery, and can run accessories. However the crankshaft pulley supplies power. Failure of the crankshaft pullingey will cause the alternator to stop turning and not produce power. 

Signs that your battery is dead will appear on the vehicle's dashboard. The lights might flicker and you won’t be able to start the vehicle for long since the battery can’t be charged. 

Reported: 8 Reasons a Car's Battery Lights On When Driving

4. Inadequate power steering pump

The car’s power steering pump is also powered up by the crankshaft pulley. This crucial component injects hydraulic fluid to the steering system, ensuring that it works as intended.

If your power steering is not working properly, you will need to exert more effort in order for the vehicle to move. You might think that the system is low on fluid, but a simple check will show that’s not the case. 

5. Broken Transmission and Internal Engine Parts

The engine vibration will cause damage to the transmission and internal engines if it is allowed to continue for too long. It can wear out the crankshaft bearings if you are unlucky, and your car’s transmission has a lot of parts that aren’t made to handle that type of vibration. Damage to the gears, shafts, and bearings is possible.

Transmission failure can cause shifting issues, fluid leakage, or whining. You don't want to have to fix a problem with your crankshaft pulley. 

Crankshaft Pulley Function

Car engines work by the energy it receives from fuel. This power can then be delivered to the other parts through various mechanical and electrical systems. The crankshaft pulley is one of these mechanical systems, and is responsible for power distribution.

All components that are connected to the crankshaft get their power from the crankshaft pulley. Although the crankshaft is responsible for driving the car's wheels, it transmits power through the pulley to other parts such as the alternator, power steering pump, and power steering pumps.

An internal dampener is included in the crankshaft pulley to reduce vibrations along the pulley belts. Unchecked vibrations could cause serious damage to any connected systems. 

Although a worn crankshaft pulley belt or defective crankshaft pulley is easy to replace, it's more difficult to fix a dampener that has broken. 

What causes crankshaft pulley failure? It can break down easily, even though it is made to last the entire life of your engine. Many models come with a rubber isolation band that can fail when it is exposed to extreme temperatures. A coolant leak or oil leak can cause the pulley to become contaminated and accelerate its deterioration. 

Crankshaft Pulley Location

On the crankshaft's end is the crankshaft pulley. Also known as a harmonic equalizer, it can be found there. It’s a wheel-shaped device with grooves that connect directly onto the crankshaft. 

The crankshaft converts straight movement into linear motion to the pistons. However, the crankshaft pulley is connected to other parts by the use of accessories belts. 

Crankshaft Pulley Replacement Cost

The cost of replacing the crankshaft pulley depends on car make and labour costs. For a brand new crankshaft pulley you could pay $200-$240 plus $150 labor.

A crankshaft pulley aftermarket can help you save money. Luxury cars may also be slightly more expensive overall. 

If you wanted to replace the crankshaft pulley yourself, the job isn’t that complicated. 

1. Take out all engine drive belts.
2. The crankshaft pulley bolt must be removed. A pulley holder is required as well as a high-torque impact wrench.
3. Take out the pulley.
4. Place the crankshaft pulley.
5. Now, tighten the bolt.
6. All engine drive belts must be replaced.