Flywheel Stuck on Crank – What to Do? Quick and Easy Solutions

Dealing with a stuck flywheel on a crankshaft can be a frustrating experience.

The flywheel plays a crucial role in maintaining your engine’s balance and timing, and when it gets stuck, it prevents efficient power transfer from the engine to the transmission.

In this article, we’ll discuss the possible causes of a stuck flywheel and provide some effective methods for removing it from the crankshaft.

When a flywheel becomes stuck, it’s often due to corrosion, dirt, or debris accumulating between the flywheel and the crankshaft.

It’s also possible that the crankshaft and flywheel have become fused together if they were not properly lubricated. By understanding the underlying issue, you’ll be better prepared to address the problem and get your engine back up and running.

To remove a stuck flywheel, various approaches can be employed, such as using penetrating oil or applying heat to the area.

Sometimes, more forceful methods like a puller or a hammer might be necessary. It’s important to use caution and ensure the safe handling of the engine components to avoid causing damage or injury.

Key Takeaways

  • A stuck flywheel can hinder efficient power transfer in your engine
  • The issue may be due to corrosion, debris, or insufficient lubrication
  • Use suitable techniques, such as penetrating oil or heat, to safely loosen and remove the stuck flywheel

Flywheel Stuck on Crank: Understanding the Problem

When working with engines, you may encounter a situation where the flywheel is stuck on the crankshaft.

This can be a frustrating and challenging problem to resolve. Here, we will discuss the problem and explore possible solutions.

A flywheel is a crucial component in your engine, responsible for storing energy and maintaining the engine’s rotational balance.

The crankshaft, on the other hand, converts linear motion into rotational motion.

Over time, due to various factors such as rust, debris, and misalignment, the flywheel may become stuck to the crankshaft.

To address this problem, you should take a few essential steps:

  1. Inspect the connection: First, ensure that all the bolts connecting the flywheel to the crankshaft are removed. Sometimes a single missed bolt can prevent the flywheel from being dislodged.
  2. Use penetrating oil: Apply penetrating oil around the center of the flywheel where it contacts the crankshaft. This helps to break down any rust or debris, making it easier to remove the flywheel.

  3. Apply heat: Using a heat gun or a torch, apply heat evenly around the flywheel’s center. The heat will cause the surrounding metal to expand, loosening the connection between the flywheel and the crankshaft.

  4. Strike with a mallet: Use a rubber mallet or a dead blow hammer to gently strike the flywheel, causing small vibrations that may break the friction holding it in place.

When using these methods, it’s crucial to exercise patience and caution. Excessive force, heat, or improper technique can cause damage to your engine components.

Analyzing the Flywheel and Crank Connection

When dealing with a flywheel stuck on the crankshaft, it’s essential to analyze the connection between the two components.

The first step is to inspect the bolts and ensure they are all removed. This might require using a socket or wrench to loosen the bolts around the flywheel.

Once the bolts are removed, you can attempt to use a flywheel puller to separate the flywheel from the crankshaft.

A flywheel puller is a tool designed specifically for this purpose and can provide the necessary force to dislodge the component.

Sometimes, the flywheel might be stuck due to corrosion. In this case, you can apply a penetrative oil, such as WD-40, around the crankshaft area of the flywheel and let the oil work its magic.

After that, tap the surface gently with a rubber or steel hammer to dislodge it.

Heating the area around the flywheel and crankshaft can also aid in loosening the connection.

Be cautious when applying heat, as it can cause damage to nearby components if not used carefully.

If you notice the key, which is a small piece of metal used to lock the flywheel in place, is worn or damaged, it might require replacement.

This can also contribute to the flywheel being stuck on the crankshaft.

Remember to take your time and exercise patience when dealing with a stuck flywheel.

With the right tools and techniques, you’ll successfully separate the flywheel from the crankshaft.

Other Methods to Unstick a Flywheel

Using Heat

Applying heat to a stuck flywheel can help expand the metal and loosen its bond to the crankshaft. You can use a propane torch to heat the area around the interference fit:

  1. First, spray some PB blaster to help lubricate the connection.
  2. Then, apply heat with the torch for a few minutes, focusing on the area where the crankshaft goes through the flywheel.
  3. Finally, carefully tap the flywheel with a hammer while it’s hot to break it free from the crankshaft.

Caution: Be sure to work in a well-ventilated area, away from flammable materials, and use proper safety equipment when working with a torch.

Also Read: Rivet Stuck in Gun

Using a Hammer

Sometimes, gently tapping the flywheel with a hammer can help unstick it:

  1. Spray some PB blaster around the connection to help loosen the bond.
  2. Use the back of a hammer to gently tap the edge of the flywheel, working your way around its circumference.
  3. Apply equal pressure on the flywheel to prevent any damage.

Note: Be careful not to hit the flywheel too hard or you may cause damage to it or the crankshaft.

Using a Pry Bar

A pry bar can be used to apply even pressure on the stuck flywheel:

  1. Lubricate the area around the crankshaft and flywheel with PB blaster.
  2. Secure the pry bar between the flywheel and the crankshaft, taking care not to damage either component.
  3. Apply steady pressure on the pry bar to carefully separate the flywheel from the crankshaft.

Warning: Be cautious when using a pry bar to avoid damaging any surrounding components.

Using a Steering Wheel Puller

A steering wheel puller is an excellent tool for removing a stuck flywheel:

  1. Spray PB blaster on the connection between the flywheel and the crankshaft to help loosen any friction.
  2. Attach the steering wheel puller to the center bolt of the flywheel and secure it in place.
  3. Use a breaker bar to apply even pressure on the puller, gradually separating the flywheel from the crankshaft.

Advantages: A steering wheel puller is designed specifically for this task and often delivers the best results, while reducing the risk of damage to the components.

Comparison Table

Using HeatEffective for stubborn stuck flywheelsRisk of burns, possible fire hazard
Using a HammerSimple, requires minimal toolsCan damage flywheel or crankshaft if not careful
Using a Pry BarApplies even pressureRisk of damaging components
Using a Steering Wheel PullerDesigned for the task, less risk of damageMay require purchase of additional tool

After the Flywheel is Unstuck

Retreading the Shaft

Once you have successfully unstuck the flywheel from the crank, it’s important to retread the shaft.

In some cases, the threads may have been damaged during the removal process.

You can use a tap and die set to create a new thread on the shaft. This will ensure that the flywheel nut can be securely fastened.

Flywheel Stuck on Crank

Replacing the Flywheel Nut

When you remove the flywheel, it’s a good idea to replace the flywheel nut with a new one.

This will prevent any potential issues that may arise from using a damaged or worn nut.

Consider using a grade 8 bolt, which provides higher durability and strength. Ensure the correct torque specifications are followed when tightening the new flywheel nut.

Preventing Future Sticking

To avoid a stuck flywheel in the future, you can take preventive measures such as:

  • Applying a thin layer of anti-seize compound to the crankshaft before reinstalling the flywheel.
  • Properly torque the flywheel to the correct specifications.
  • Periodically checking for signs of wear and rust, and addressing these issues promptly.

Checking for Damage

Lastly, inspect the flywheel, crankshaft, and other components for any signs of damage that may have occurred during the removal process.

Examples of damage could be warped flywheel surfaces, cracked crankshaft arms, or grinding marks causing uneven surfaces.

Any damaged components should be replaced or repaired before reassembling the engine. This will ensure your engine operates smoothly and prevent any additional complications.


In order to remove a stuck flywheel from a crankshaft, there are several steps that you can follow:

  1. Apply penetrating oil: Spray a liberal amount of oil around the area connecting the flywheel to the crankshaft. Let it sit for some time to allow the oil to penetrate the rust and corrosion.

  2. Light tapping: After letting the penetrating oil soak in, gently tap the flywheel with a rubber mallet or a hammer with a piece of wood in between to avoid damage.

  3. Heat application: If the flywheel still does not budge, apply heat around the connection using a propane torch or a similar heat source. Be cautious not to overheat the surrounding components.

  4. Using a pry bar: Carefully insert a pry bar or a large flathead screwdriver between the flywheel and the engine block. Gently pry, applying leverage to loosen the stuck flywheel. Exercise caution not to damage any engine components.

Remember, patience and persistence are key when attempting to remove a stuck flywheel from a crankshaft.

Don’t force the process, as it may result in damage to the flywheel or other engine components. With the right approach and tools, you’ll be able to successfully remove the flywheel from the crankshaft.

Frequently Asked Questions

How can I remove a stuck flywheel without a puller?

You can place wedges between the flywheel and the block plate at the midline to create pressure while leaving a couple of bolts loosely installed to catch the flywheel. Then, strike the flywheel with a dead blow hammer.

What tools can be used for flywheel removal?

Common tools for flywheel removal include a puller, wrenches, an impact wrench, and a dead blow hammer. Another method involves using a torch to heat the area around the flywheel for easier removal.

How to prevent a flywheel from spinning during removal?

To prevent the flywheel from spinning, you can use a flywheel holding tool or a large screwdriver to securely hold it in place. Position the tool or screwdriver in a way to prevent the flywheel from rotating as you loosen the bolts.

How do I remove a 2-stroke engine flywheel?

To remove a 2-stroke engine flywheel, use a flywheel puller specifically designed for 2-stroke engines. Attach the puller to the flywheel, and turn the puller’s center bolt clockwise to create tension. The flywheel should eventually come off.

What’s the process for removing a flywheel nut without an impact wrench?

You can remove a flywheel nut without an impact wrench by using a breaker bar and a socket. Hold the flywheel securely using a flywheel holding tool or screwdriver to prevent rotation. Loosen the nut with the breaker bar until it can be removed by hand.

Any tips for dealing with a chainsaw flywheel that’s stuck?

Ensure all elements are clear of debris, then apply penetrating oil to the area around the flywheel.

You can then use either a flywheel puller or strike the backside of the flywheel using a soft-faced hammer, while ensuring to protect the flywheel from damage. Remember to work patiently to prevent further damage to the chainsaw.

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Sean Mendez

Hi, I am Sean, a self-confessed petrolhead. I live in Boise, Idaho with a busy family of four and our energetic Labrador retriever. Thank you for visiting my website. You can find my email on the contact page.

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