How to Replace a Broken Clock Suspension Spring

A clock’s suspension spring is one of the most important—and delicate—components in any pendulum-driven movement. When it fails, your clock will stop ticking, lose time, or swing erratically. Learning how to replace a broken clock suspension spring is essential for restoring proper operation and protecting the rest of the clock movement from damage.

Step 1: Understand the Suspension Spring’s Role

The suspension spring is a thin, flat strip of metal that holds the pendulum in place while allowing it to swing freely. It connects the pendulum leader to the suspension post on the clock movement.

Without this part, the pendulum cannot regulate the escape wheel, and the clock will stop or run wildly out of time.

A healthy suspension spring:

• Allows smooth side-to-side pendulum movement
• Supports the weight of the pendulum
• Provides flexibility without bending or cracking

Step 2: Identify Signs of a Broken Suspension Spring

Recognizing a failed suspension spring early can prevent damage to other parts of your clock. Watch for these common symptoms:

Clock stops running — The clock will no longer tick when the pendulum stops receiving power from the escapement.

Pendulum falls off or sags — The pendulum may detach completely or hang crooked.

Clock runs fast or erratic — If the spring partially fails or twists, the pendulum may swing too quickly, causing fast timekeeping.

Visible damage to the spring — Look for cracks, kinks, or broken ends on the thin metal strip.

Step 3: Measure the Suspension Spring

Before ordering a replacement, take accurate measurements to ensure the new spring fits properly.

1. Remove the broken suspension spring from the clock carefully.
2. Lay it flat on a clean surface.
3. Measure the total length, including the top and bottom blocks.
4. Measure the width of the metal strip (not just the blocks).
5. Check the thickness if possible (most are between 0.003” and 0.005” thick).
6. Count the number of loops or hooks on the ends, if present.

If the spring is completely missing or mangled, check your clock’s manual or contact Clockworks with the clock’s make, model, and movement number for help choosing the right size.

Step 4: Gather the Right Tools

You’ll need:

• Small screwdrivers
• Needle-nose pliers
• Caliper or ruler (for measuring)
• Clock oil (for reassembly)

Clockworks also carries precision clock tools to make installation easier and safer.

Step 5: Remove the Old Suspension Spring

1. Remove the clock’s movement from the case carefully.
2. Locate the suspension post at the top of the backplate.
3. Unscrew or unclip the suspension spring from the post.
4. Detach the lower end from the pendulum leader.

Take photos or notes as you go to remember the correct orientation.

Step 6: Install the New Suspension Spring

1. Attach the top of the new suspension spring to the suspension post. Ensure it is centered and secure.
2. Attach the lower end to the pendulum leader. Make sure the pendulum hangs straight and the leader moves freely.
3. Double-check that the spring sits flat without twists or bends.

Step 7: Test and Adjust the Clock

After installation:

1. Reinstall the clock movement into the case.
2. Hang the pendulum on the leader.
3. Start the pendulum swinging gently.
4. Listen for an even, steady tick-tock sound.
5. Use the rating nut on the pendulum bob to adjust timekeeping.

If the pendulum swings unevenly, check for:

• A twisted or bent suspension spring
• A misaligned suspension post or leader
• An unlevel clock case

Step 8: Maintain the Suspension Spring

To extend the life of the new spring:

• Handle the pendulum carefully when moving the clock.
• Avoid twisting or over-bending the spring.
• Check the spring during regular clock maintenance every 2–3 years.

Common Mistakes to Avoid

Using the wrong size spring — Always measure carefully or get help identifying the right part.

Forcing the installation — Never twist or bend the spring to make it fit.

Neglecting clock level — An uneven clock case can make the pendulum swing improperly, even with a new spring.

Skipping testing — Always test the clock after installation to ensure smooth operation.

Summary

Replacing a broken suspension spring restores your clock’s accuracy and extends the life of its movement. By understanding its role, spotting failure signs, measuring precisely, and installing carefully, you can bring your clock back to life with confidence. Use quality tools, handle parts gently, and test thoroughly after installation. For the right springs, parts, and tools, visit Clockworks.com or email clockworks@clockworks.com — we’re here to help keep your clocks ticking beautifully.

Updated on: 28/09/2025