Nothing happens if your lawn mower pull cord isn’t catching. If your mower has a pull cord, there’s usually no way to get your mower to start, which ruins your mowing mission. It’s incredibly frustrating to do other troubleshooting to find out why your mower won’t start and realize that it’s not just that your mower needs some extra gas, but that the pull cord is faulty. In this article I’ll explain how the lawn mower pull cord mechanism works, possible causes for your lawn mower pull cord not catching, and how to fix the issue.
Why Your Lawn Mower Pull Cord Isn’t Catching
The pull cord mechanism on a lawn mower isn’t complicated, and the reason your cord isn’t catching is that one of the components of the flywheel starter assembly has failed under the stress of regular use. Typically it’s either worn or broken pawls, or a damaged pulley system. Either way, a complete OEM replacement starter assembly will typically cost less than $30 and it’s an easy DIY fix that takes a couple of minutes.
About the Starter Assembly
The starter rope is the only part of the starting system that can be seen. But inside your mower, the rope activates a series of parts that start the engine.
Learning how the mechanism functions will allow you to know how to fix a lawn mower pull cord that isn’t catching.
Sometimes the repair is simple, where the pull cord or handle itself breaks. If this is the case, simply replacing the rope or handle will be enough, and that’s a job that anyone can do.
Other issues can be the cause as well, but the good news is that these also have relatively simple fixes.
Let’s start by explaining how the pull cord on a lawn mower works, and then I’ll explain the usual reasons your cord isn’t working and tell you how to fix each one individually, and how to search for and find a brand new OEM starter assembly for your mower (what I recommend since the cost is still pretty low).
How Your Lawn Mower Pull Cord Works
When you pull the rope to start your mower, it engages the starting mechanism, which turns the engine fast enough to spark the ignition module.
The starter rope is wrapped around a pulley system. That allows it to be pulled out before it recoils into the engine. The pulley sits below the cover at the top of your walk-behind mower, and a spring is in the center of the pulley. As it’s turned, the recoil spring stretches, then snaps back when let go. This immediate snap-back retracts the pull cord and allows you to pull the rope quickly one time after another.
The recoil operates the mower’s flywheel. The flywheel sits below the starter, closer to the mower, and near the crankshaft. Magnets sit on the outside of the flywheel and generate magnetic energy as it spins. The magnets will eventually build up enough energy to fire off high-voltage sparks.
The pawls are also attached to the pulley. These are plastic wings that spin out due to the centrifugal force, helping to catch the flywheels and create a faster spinning movement.
The crankshaft is in the center of the flywheel and turns with the flywheel. As the crankshaft turns, it helps the piston move up and down, pushing more gas and air into the mower’s system. If it can’t spin fast enough, the engine won’t start.
The pawls are the most likely component to fail and it’s probably why your mower isn’t starting. That said, if the pulley or receiver is damaged, that will also cause issues.
Lawn Mower Pull Cord Not Catching: Possible Causes
There are two very common causes for a lawn mower pull cord not catching. These include:
- Broken or Worn Pawls, or a
- Damaged Pulley.
Let’s take a closer look at each of these, and other possible causes for this mower issue.
Broken or Worn Pawls
On most modern mowers, the pawls are usually made of plastic, though some brands use metal pawls.
Metal pawls are far more durable. This component is exposed to tension from spinning out, as well as catching the flywheel.
Since this part is designed to spin out and catch the flywheel, if they’re worn out or broken, they won’t be able to do that. That prevents the engine from turning over, and it’s usually the reason you pull your mower starting cord and it doesn’t catch.
In other words, it will feel like the pull cord is pulling too freely.
To check if the pawls on your mower are broken, remove the starter and pull the rope to make them pull out. If they don’t pull out, either they’re broken or something else is broken.
To repair worn or broken pawls.
- Unplug the spark plug wire before starting the repair. This prevents the motor from starting, and is an important safety step whenever doing any work on your mower.
- Disassemble the housing (the top cover) to expose the pull cord assembly.
- Remove the center bolt and cap in order to pull the pawls out.
- Inspect the pawls and determine whether they’re damaged or worn.
- Insert the new pawls, then re-install the center bolt and cap, as well as the starter, into the engine.
The pull cord should catch again and allow the engine to start. If the pull cord continues to not work, the issue may be something else interfering with the pawls.
The mower’s pull cord rope is stored in the pulley, as well as the recoil spring. The pulley will guide and feed the pull cord, in addition to storing it. Pulleys are usually made from plastic and this is a part that can crack.
A broken or cracked pulley will interfere with the rope pulling around the pulley. If it malfunctions or jams, the starter system will not work.
To replace the pulley, you’ll need to remove the starter system.
- Again, start by disconnecting the spark plug wire.
- Next, pull the rope out, then insert a screwdriver to secure the recoil spring and pulley.
- Remove the rope, then release the screwdriver to allow tension to return to the spring.
- Remove the center bolt and friction plate, which will release the pulley.
- Now you can place the new pulley, first aligning it with the housing post.
- Rotate the pulley, since that will tighten the spring, then insert the screwdriver to hold it in place so you can reattach the rope.
- Release the screwdriver and let the rope slowly wind up. You can then place the starter back onto the engine, reassemble, and try to start your mower.
Replacement pulleys can be bought either as just the cover or with the recoil spring combined.
It’s usually easiest to replace both simultaneously. It’s a little more expensive, but for most homeowners tackling this project it makes sense to replace the entire unit as it’s simpler.
The spring can be difficult to work with, and purchasing the entire assembly won’t add too much additional cost to the repair. In my view, it’s worth it.
Other Issues Which Can Make Your Pull Cord Not Catch
While these are the most common issues with the pull cord system, they are not the only ones that can occur.
Different lawn mower brands make their components differently. Some will use plastic instead of metal for certain components. Plastic parts will wear out faster, and are less capable of withstanding the stresses of consistent use.
The reality is that if you’re buying a new mower, you’ll find that more brands are using plastic for the flywheel receiver to cut costs and remain competitive with their price.
The flywheel receiver is a metal cup that fixes to the flywheel. This is the component the pawls will connect to. If they’re worn in addition to (or instead of) the pawls, the engine will also not catch.
Receivers are less likely to cause issues unless they’re made of plastic, but since more modern mower manufacturers are using plastic for this part, it will probably become a more common cause of failure and a reason why your lawn mower pull cord may not be catching.
Older mowers which have metal components are likely to have fewer issues, even if they’ve been used for more hours. This is one reason why it might make sense to buy a used mower instead of buying new.
Can You (and should you) DIY the Fix?
If you’re handy and like working with mechanical parts, it’s pretty easy and inexpensive to replace part or all of this component on your mower.
You’ll want to know your brand and mower model. Then you can search online for your mower brand, model number, and starter/recoil/flywheel assembly OEM.
If you’re unsure of your lawn mower model number, you can find it on a small plate on your mower. It will be alongside the mower’s serial number.
For example if I had a Honda HRN216VKA self-propelled mower I bought from Home Depot, I could search honda HRN216VKA starter assembly OEM on Amazon and quickly find the part I need for under $30.
About Tackling This Project
Like most small engines, disassembly and reassembly is pretty straight-forward. But I always recommend taking pictures of each step so you can remember where everything went as you put the mower back together.
If you’re intimidated by the idea of doing this work yourself, you have a few options. You can:
- Check to see if your mower is under warranty. If it is, you can probably get this repaired at no cost.
- Contact a local small engine repair shop. It should be an inexpensive job that can be completed quickly. They can also do a tune-up of your machine, change the oil, and sharpen your mower’s blades for you while it’s in for servicing.
The bottom line is that this is not a major issue with your mower (even if it feels like one). You shouldn’t send your mower to the scrap heap and rush out to buy a new mower.
It’s worth fixing, and most homeowners (even those who are not mechanically inclined at all) can replace the starter assembly on a walk-behind mower.
Maintaining Your Mower
These quick (and easy) maintenance projects at the start and end of each season will keep your mower running great for years.