The pull string breaks because it frays where it loops through the handle, or snaps inside the engine housing where tension is highest

Replacing a lawn mower pull string takes 15 to 30 minutes and costs $5 to $15 for the cord itself. You do not need special tools — a screwdriver, scissors, and a lighter are enough. The job splits into two parts: removing the old cord from the recoil housing (the spring-loaded drum under the handle) and threading new cord back through it, then reattaching the handle.

Most pull strings fail at the handle knot or inside the recoil assembly where the cord wraps around a spool. If your mower will not start and the handle feels slack or does not catch, the cord has likely snapped. Replacing it restores the spring tension that cranks the engine.

Key Takeaways

  • Lawn mower pull cord is sold as bulk rope at hardware stores and online; common sizes are 3.5 mm and 4 mm diameter, and you need roughly 12 to 15 feet depending on your mower model.
  • The recoil housing sits under the handle and contains a spring-loaded spool; you must remove the spark plug wire first to prevent accidental starting while you work.
  • The old cord is knotted at both ends — one knot sits in the handle grip, the other is buried in the recoil spool — and both must be cut free before you can pull the cord out.
  • Threading new cord back through requires feeding it through the handle, into the recoil housing, and around the spool while the spring is under tension, which is easier with a helper or a clamp to hold the spool in place.
  • The final knots must be tight and sealed with a lighter to prevent fraying, and the handle must rewind smoothly without binding or slack.

Identify your mower model and cord size before buying replacement cord

Pull cord diameter varies by mower. Most residential mowers use 3.5 mm or 4 mm rope. Check your mower's manual or look at the recoil housing — if you can see the old cord still threaded through, measure its thickness with a ruler or caliper. If the cord is completely gone, call the mower manufacturer with your model number and ask for the correct diameter and total length.

Buy rope at a hardware store or online under the name "pull cord", "starter cord", or "recoil cord". Nylon braided rope works best because it resists fraying. Buy 15 to 20 feet so you have extra for mistakes. The cost is usually $0.50 to $1.00 per foot.

Remove the spark plug wire and locate the recoil housing

Before touching any part of the mower, disconnect the spark plug wire by twisting the rubber boot and pulling it straight off the plug. This prevents the engine from starting accidentally while you work. Lay the wire aside where it cannot touch the plug.

The recoil housing is the plastic or metal drum mounted under the pull handle on top of the engine. It usually has a circular cover with a hole in the center where the spool sits. Some mowers have the housing bolted to the engine; others have it clipped on. Look for bolts or clips around the edge of the cover.

Remove the handle and cut out the old cord

The handle is usually screwed or bolted to the recoil housing cover. Use a screwdriver or wrench to remove these fasteners and lift the handle away. You will see the old cord knotted inside the handle grip — cut this knot free with scissors or a utility knife.

Next, remove the recoil housing cover by unbolting or unclipping it. Inside, you will see the spool (a round drum) with the old cord wrapped around it. The cord is knotted at the center of the spool. Cut this knot free as well, then pull the old cord out completely. Discard it.

Thread the new cord through the recoil spool while managing spring tension

The spool sits on top of a spring. When you removed the old cord, the spring lost its tension. You now need to wind the new cord around the spool while keeping the spring compressed. This is the trickiest step and is much easier with a helper or a C-clamp.

If working alone, use a C-clamp to hold the spool in place against the spring pressure. Feed one end of the new cord through the center hole of the spool from underneath. Pull the cord up and out through the top, then tie a tight knot at the center of the spool — the knot should sit in the spool's groove so it does not slip. Trim the excess cord and seal the knot with a lighter by melting the nylon slightly; this prevents fraying.

Now wrap the cord around the spool in the same direction the old cord wrapped (usually clockwise when viewed from above). Wind it tightly, layer by layer, until the spool is nearly full. Leave enough cord to thread up through the handle and out to the grip.

Feed the cord through the handle and tie the grip knot

Thread the free end of the cord up through the hole in the recoil housing cover, then through the hole in the handle grip. Pull the cord taut so there is no slack between the spool and the handle. Tie a knot inside the handle grip large enough that it cannot slip back through the hole. Trim the excess and seal this knot with a lighter as well.

Reattach the handle to the recoil housing cover using the original bolts or screws. Make sure the handle sits flush and does not rock.

Test the pull cord and rewind the spring

Before reassembling the mower, test the pull cord by pulling the handle slowly. It should pull smoothly without binding, and the handle should snap back quickly when you release it. If the handle does not rewind or pulls too hard, the spring tension is wrong — the cord may be wrapped too tightly or the spring may not be seated correctly.

If the rewind is sluggish, remove the handle again and check that the cord is wrapped evenly around the spool with no kinks or overlaps. If the handle pulls too hard, you may have wound the spring too tight; loosen it slightly by rotating the spool counterclockwise one or two turns.

Once the pull cord works smoothly, reattach the recoil housing cover to the engine and reconnect the spark plug wire. Start the mower to confirm the new cord works under load.

Frequently Asked Questions

What size pull cord do I need if I cannot find my mower manual?

Call the mower manufacturer with your model number — it is usually stamped on the engine or frame. They will tell you the exact diameter and length. If you cannot reach them, 4 mm diameter is the most common size for residential mowers, and 15 feet is a safe length for most models.

Can I use regular rope instead of braided nylon cord?

Braided nylon is much better because it resists fraying and holds knots tighter. Regular rope will fray quickly where it wraps around the spool and where you tie the knots. If you use regular rope, seal every knot with a lighter to slow fraying.

The spring keeps pushing the spool back when I try to wind the cord — how do I hold it in place?

Use a C-clamp or bar clamp to hold the spool against the spring pressure while you wind. Clamp it to the spool and the housing so it does not rotate. This is much easier than trying to hold it by hand, and it prevents the spring from unwinding suddenly and pinching your fingers.

How tight should the knots be?

Both knots should be tight enough that they do not slip under hand pressure. Tie each knot twice (a double knot) and seal it with a lighter by melting the nylon slightly. The melted nylon will harden and lock the knot in place, preventing it from coming loose during use.

What if the pull cord still does not work after I replace it?

Check that the spark plug wire is reconnected and the mower is not flooded with fuel. Pull the cord slowly and feel for resistance — if it pulls too hard or feels stuck, the spring may be over-wound or the cord may be kinked inside the housing. If the handle does not rewind, the spring may be broken and will need to be replaced as a complete recoil assembly.