What You Need to Know Before You Start
A broken pull cord is one of the easiest lawn mower repairs you can do yourself, and you can finish it in 30 to 45 minutes with basic tools. The cord itself costs $8 to $15, and you likely already own everything else you need. The hardest part is not the repair—it's finding the right cord diameter and length for your specific mower model, because these vary widely.
Before you buy anything, you need three pieces of information: your mower's make and model (usually on a sticker near the engine), the diameter of the old cord (typically 3.5mm or 4mm), and the total length (usually 40 to 50 inches, but this varies). Write these down or take a photo of the model sticker. You can find the correct cord at any hardware store, online retailer, or directly from the mower manufacturer.
Key Takeaways
- You need the mower's make, model, and the old cord's diameter and length before buying a replacement—these details are on the model sticker and the old cord itself.
- The repair requires only a screwdriver, pliers, and the new cord; the entire job takes 30 to 45 minutes and no special skills.
- The hardest step is re-winding the recoil spring, which requires patience but no tools beyond what you already have.
- If the recoil spring is broken or the handle is cracked, you will need to replace those parts as well, which costs $20 to $40 more.
Gather Your Tools and Materials
You need very little to do this job. Lay out a screwdriver (usually Phillips head, sometimes flathead—check your mower), a pair of pliers, the new pull cord, and a small bowl or cup to hold screws so you do not lose them. Some people find a work light helpful because the recoil housing is often dark inside.
Before you start, disconnect the spark plug wire from the spark plug. This is the wire running from the engine to a plug on top of the engine. straightforward pull it straight off. This prevents the engine from accidentally starting while you work. Set it aside where you can see it so you remember to reconnect it when you are done.
Remove the Recoil Housing and Old Cord
The pull cord lives inside a plastic or metal housing bolted to the side of the engine. Locate this housing—it is the round or oval cover with the handle sticking out. Use your screwdriver to remove the bolts holding it to the engine. Most mowers have three to five bolts. Place each bolt in your bowl as you remove it.
Once the housing is loose, gently pull it away from the engine. You will see the recoil spring inside—a tightly coiled metal ribbon. Be careful not to disturb it. The old cord is wound around a pulley or spool in the center. Cut the old cord with scissors or a knife and unwind what remains. If the cord is knotted to the handle, untie it or cut it free. Set the handle aside; you will reuse it with the new cord.
Examine the recoil spring and the spool. If the spring is broken (you will see a gap or a loose end), or if the spool is cracked, you will need to replace the entire recoil assembly, not just the cord. This costs $20 to $40 and requires ordering the part for your specific model. If everything looks intact, proceed to the next step.
Wind the New Cord onto the Spool
This is the step that takes patience. The recoil spring is under tension, and you are about to wind the new cord in a way that keeps that tension balanced. Start by feeding one end of the new cord through the hole in the spool (the center of the pulley). Most spools have a small hole or slot designed for this. Push the cord through until about 6 inches hangs out on the other side.
Now wind the cord around the spool in the same direction the old cord was wound. Look at the spool and the spring to figure out which way that is—usually clockwise when you are looking at the spool from outside the housing. Wind slowly and keep tension on the cord with your other hand so the wraps stay neat and tight. Make four to six complete wraps, depending on your mower model. The cord should spiral around the spool without overlapping itself.
After you have wound the cord, tie a knot in the end that is still hanging out. A straightforward overhand knot works fine. This knot will sit inside the housing and keep the cord from unwinding. Pull gently on the cord to make sure the knot holds and the spool does not slip.
Re-tension the Recoil Spring
This is where most people get stuck, but it is straightforward once you understand what you are doing. The recoil spring needs to be wound tight enough that it pulls the cord back into the housing after you let go of the handle. You wind the spring by rotating the spool by hand.
Hold the spool steady with one hand and use your other hand to turn it clockwise (or counterclockwise—check which direction the old spring was wound). Turn it slowly, about one full rotation at a time. After each rotation, let go and pull the cord handle to see if it retracts smoothly. The spring is properly tensioned when you pull the handle all the way out and it snaps back into the housing on its own, without you having to push it.
Do not over-wind the spring. If the handle is hard to pull or does not come out all the way, you have wound it too tight. Loosen it by rotating the spool back one or two turns. The goal is smooth, straightforward pulling with automatic retraction. This usually takes three to five rotations of the spool, but it varies by mower.
Reattach the Handle and Test
Once the spring is tensioned correctly, thread the free end of the cord through the handle. Most handles have a hole or slot on one side. Push the cord through until it sits in the center of the handle, then tie a knot on the end so it cannot pull back through. A double overhand knot or a figure-eight knot works well here.
Trim any excess cord with scissors. You want about a quarter-inch of cord sticking out past the knot, just enough to see that the knot is there but not so much that it looks messy.
Reinstall the Housing and Reconnect the Spark Plug
Slide the recoil housing back onto the engine, lining up the bolt holes. Insert each bolt and tighten them with your screwdriver. Do not over-tighten—snug is enough. If you strip the threads, you will have a bigger problem.
Reconnect the spark plug wire by pushing it straight onto the spark plug until you hear or feel a click. Pull the cord a few times to make sure it moves smoothly and retracts properly. The handle should come out easily and snap back without resistance. If it feels wrong, stop and re-check the spring tension before you start the engine.
Once everything feels right, start the mower and let it run for a minute. The pull cord should work normally during normal operation. If the cord does not retract or is hard to pull, turn off the engine, disconnect the spark plug again, and adjust the spring tension.
Frequently Asked Questions
What if the recoil spring breaks while I am working on it?
A broken spring usually means you need to replace the entire recoil assembly. This is a $20 to $40 part that you order for your specific mower model. You cannot repair a broken spring yourself. Order the part and follow the same removal and installation steps, but you will be replacing the whole housing, not just the cord.
How do I know what diameter cord to buy?
Measure the old cord with a ruler or calipers if you have one. Most lawn mower cords are either 3.5mm or 4mm in diameter. If the old cord is gone, check your mower's manual or call the manufacturer with your model number. A hardware store can also help you match the diameter by comparing it to a sample.
Can I use any type of rope instead of a pull cord?
No. Pull cord is made from a specific material (usually nylon) that resists fraying and holds up to repeated pulling. Regular rope will fray, stretch, and wear out quickly. Always use actual pull cord rated for small engines.
Why is my new cord hard to pull?
The recoil spring is over-tensioned. Loosen it by rotating the spool back one or two turns and test again. The cord should pull smoothly without requiring extra force. If it is still hard, loosen it more.
Do I need to drain the fuel before I start?
You do not need to drain it, but disconnecting the spark plug wire is essential. This prevents accidental starting. If fuel spills while you work, wipe it up when ready and let the area dry before reconnecting the spark plug.