Cobra lawn mower problems. How to Repair a Lawn Mower Pull Cord

How to Repair a Lawn Mower Pull Cord

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Introduction

Replace a broken starter rope on your lawn mower quickly and easily by following this simple step-by-step procedure.

Materials Required

You tug one last time to get the lawn mower started, and suddenly the pull cord breaks and the end goes spinning into the hole. Don’t blow a gasket. If you have even a tinge of mechanical aptitude, replacing a starter rope is pretty easy. If the spring breaks—a rare event, according to our repair expert—the fix is a lot harder, and we recommend you take the mower to a repair center.

Stuck Cord or Broken Cord?

First, check to confirm that the cord is actually broken and not just stuck. If it’s stuck, it may be an easier fix than full pull cord replacement and you likely won’t have to buy any new parts. Here are a few tips for fixing an electrical cord.

Run through your troubleshooting checklist if your cord isn’t working. Check to ensure the brake is off, make sure there isn’t any lawn debris clogging the blade, and finally, if all else fails, use our steps below to open the rewind unit. There, you’ll be able to see if the cord is stuck or fully broken.

What to Know About Replacement Cords

Different lawn mowers need different types of pull cords. If you don’t have time to spend looking for the right match, you can opt to get the thinnest kind, which will fit no matter what. But the thinner the cord, the more likely it is to break again soon. If you don’t already have replacement cord on hand, go to your local hardware store with the broken cord. The associates there should be able to help you get the exact kind you need.

Lawn Mower Not Picking Up Grass? Try These 9 Easy Fixes

One of the great things about lawn mowers are the leftover grass clippings.

Yes, you read that right. The leftover clippings are great. Now they can be a slight pain to clean, especially when they stick to your legs and shoes after taking care of your lawn on a nice day. But that’s the basic cost of doing business.

What you can’t deny is their usefulness. Clippings can be used as mulch for flower beds or in composting bins. They can also just be left where you mowed to decompose and become natural fertilizer for your lawn.

If you think of it, that’s one of the benefits of having a grass catcher bag for your mower. It doesn’t have to be there to catch grass so you can throw those clippings away. It can help transport your clippings to your flower beds or composting bins. Grass catcher bags become your easy and efficient clippings transporter.

That is, unless the lawn mower isn’t catching grass as it’s designed to.

If your mower isn’t picking up grass the way it’s supposed to, don’t worry. Below you’ll find nine easy fixes to try out on your mower and hopefully correct whatever the issues may be.

So, let’s get to fixing so your mower can get back to picking…up grass like it was designed to!

Try These 9 Fixes

The Grass Catcher Bag is Already Full

Perhaps you just started mowing or haven’t mowed enough for the bag to already be full. It doesn’t mean the bag isn’t worth checking out and making sure it is, indeed, empty.

Don’t shake your head just yet. Think about it. The last time you mowed, did you remember to empty the bag when you were done? Maybe you were in a hurry and just put the mower away and forgot to take the bag off and empty it.

Worse mistakes have been made. Also, it doesn’t hurt to check to eliminate it as a possible problem. If it is full, well, you’ve identified the problem. Now you need to empty it and move on.

The Grass Catcher Bag is Installed Incorrectly

If this is the issue, it’ll take you about five seconds to realize it. Start mowing and look at the bag. Do you see grass clipping blowing out of a section between the mower and the bag?

If the answer is yes, then you know the bag is installed incorrectly, particularly at the spot where the clippings are blowing out instead of in.

This should be an easy fix.

The Grass Catcher Bag is Damaged

If you’re doing a visual inspection of your mower before using it, you should pick up on any damage to the catcher bag as part of your pre-mowing ritual. However, the catcher bag is also an item that’s easy to overlook since it doesn’t have anything to do with starting and stopping the mower itself.

Also, it is a bag and is prone to tearing. Or it may be older and years of use and natural deterioration have caught up to it. It’s not surprising to once and a while find damage that can cause the grass to miss the bag completely.

If you do find damage, you’ll probably have to replace the bag. At a minimum, you’ll have to do a temporary repair. Either way, you’ve found the issue.

The Grass Shoot is Clogged

Here’s a good reason to clean after every mow. It’s also one of the areas often missed after a mow.

Yes, you swept up. Wiped down the mower. Emptied the bag. You did everything you were supposed to.

Maybe you forgot to make sure the grass shoot was cleared. You know, the little space that separates the underside of the mower from the catcher bag? It’s one of the easiest places for clippings to collect and, if damp, get matted down and clog the path.

If it does have grass collected in it, go ahead and clean it out and see if that helps correct your issue.

Speaking of Mower Blades

While you’re inspecting your grass shoot, take a look at your mower blades. Are they damaged? Are they installed correctly?

Blades that are damaged will work inefficiently, which means your grass will be mowed inefficiently. That doesn’t just mean a badly cut lawn, it might mean hardly any cutting at all. This would explain why you have hardly any to zero clippings being picked up. Your blades just aren’t cutting or cutting enough to pick up.

If the blades are installed incorrectly, or upside down, your mower won’t be creating an effective vacuum under the mower deck. That will prevent clippings from being sucked into the bag. The easiest way to check the installation is to visually inspect the position of the sail (the part of the blade that curves).

If it curves up toward the deck, it’s installed correctly.

If, however, it’s curving down, then the blade is cutting but naturally knocking the clipping back down to the ground instead of up and into the bag.

Uneven Ground

Are you mowing on uneven ground?

Are you mowing any area outside of the area you would normally mow? In other words, was your mower picking up grass just fine anytime you were mowing your nice, flat lawn but today you decided to mow a hill or ditch and now your mower is having issues picking up grass?

Well, if you’re mowing uneven ground and now having problems catching grass, it’s probably because you’re mowing uneven ground and the mower is doing what it’s designed to do.

Think of it this way. If you’re mowing a narrow ditch, for example, and the wheels on the left side of the mower are on the side of the ditch that slopes up one way and the wheels on the right side of the mower are on the side of the ditch that slopes up the opposite way, how much space do you have under your mower?

space than your regular lawn.

If you can imagine it, you have a lot more space under your mower than your blades would normally cut. space under your mower means less vacuum under your mower. This leads to more clippings on the ground and less in the bag.

The same goes for any terrain that causes part of your mower to be higher than another part. If the grass under the blades isn’t pretty even, you’re going to have inefficient grass pick-up.

Mower Wheel Height

This time, though, you haven’t let the grass get as high or thick but did you lower the wheels back down since last time?

It’s another one of those things that’s easy to overlook but wheel height can have the same effect as mowing uneven terrain. If the wheels are higher and the grass is shorter, your mower will have more room under the blades. room means more clippings on the ground and less in the bag.

Wet Grass

If the grass is wet, you probably already know this is more than likely the problem you’re having. Mowers and wet grass aren’t friends and wet grass doesn’t like to be picked up.

No, wet grass likes to mat and clump and collect on the surface area under your mower deck and on the blades and in the grass shoot.

Wet grass pretty much likes to collect everywhere but in the catcher bag.

Wait until the grass dries and try again. You’ll more than likely be picking up grass with little to no issues.

Speed

Okay, your mower is running and cutting. You’ve addressed the other issues listed so far and everything seems to be just fine but your mower still isn’t picking up grass clippings.

If this is the case then you need to ask yourself does the mower sound like it normally does? When you’re pushing and mowing, does it sound the same or weaker? Are there periods where it feels like the blades may be spinning faster, then slower, then faster again? Or does it feel like it’s just slower, even though your power supply is good to go?

If this is the case, then you may have engine or motor issues (depending on the type of mower you have) or even a drive system issue. You should, at this point, consult your manufacturer’s manual for troubleshooting problems with mower RPMs and drive controls.

Conclusion

When you have a mower that’s designed to pick up grass and isn’t doing it, it’s easy to get frustrated.

However, if you walk through the nine possible issues above, you’ll more than likely find the solution is simple and easy to address without letting frustration get the better of you.

I’ve been helping homeowners with appliance repair since 2016. Starting out as an enthusiastic amateur, I’ve since worked with many Appliance, HVAC, and DIY experts over the last 7 years. My mission is to help your fix your appliances and systems. saving you money and lowering your energy bills. Visit my author page to learn more! Read more

Hi there! My name’s Craig, and I started Appliance Analysts back in 2017.

My mission is to help our readers solve appliance-related issues without paying through the nose for contractors or a whole new model. I’m joining up with experts from across the HVAC, Appliance Repair, DIY industries to share free expert advice that will save you time, stress, and money.

Lawn Mower Pull Cord Not Catching (How to Fix)

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:

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.

Damaged Pulley

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

If you’re looking to keep your mower in top shape, read my articles on winterizing your mower, and my spring mower tune-up checklist.

These quick (and easy) maintenance projects at the start and end of each season will keep your mower running great for years.

Why Does My Lawnmower Backfire? How can I fix it?

After working smoothly for some time, your mower starts backfiring unexpectedly. Engine backfire can quickly leave the owner or operator in distress because a backfire can be loud and frightening. A backfire is just like a small explosion, it is not dangerous most of the time, but the causes behind a backfire could be hazardous for your engine. If your mower’s engine backfires and you understand why it does so, you can fix the problem and make sure it does not do it again so you can keep using your mower like normal. Backfires happen unexpectedly and mostly catch you off guard while turning off or starting your engine, so it is beneficial to have at least the basic info about engine backfires and how to deal with them.

Why Does My Lawnmower Backfire, and how can I fix it:

Backfires occur when fuel comes close to a spark outside the engine combustion chamber and is either fuel-related or engine-related. Sometimes, fuel can escape your engine’s cylinder before the valves close or during the exhaust stroke and enter the engine or exhaust. If a sufficient amount of unspent fuel manages to enter the engine and comes close to the spark, it will ignite, causing a small engine explosion. Combustions of fuel anywhere in the engine other than the combustion chambers or in the exhaust will always produce a bang or backfire.

Engine backfires are caused by basic and simple chemical malfunctions, and solving the backfiring problem is not difficult. It is necessary to fix the issue as soon as possible so that the engine and exhaust are not damaged beyond repair. Information about engine backfiring in lawnmowers presented in this article will surely help you manage a backfiring situation in a better way.

What is the cause of a Lawn Mower Backfire?

Generally, a lawnmower backfires because the fuel mix being too lean. This means there is more air in the gas mix, and it results in incomplete combustion. The gas that is pushed to the exhaust will still contain gas. When it reaches the exhaust, this gas will exnight spontaneously and makes a bang sound. This is the backfire.

Backfiring in a lawnmower and other Small Engines:

Lawnmower engines are regarded as “small” internal combustion engines. Power is produced in internal combustion engines by the combustion of an air-fuel mixture in the engine’s combustion chamber. This production of power takes place in either 2 strokes or 4 strokes. In both cases, combustion of the air-fuel mixture is the most vital stroke in which a spark ignites the mixture, causing an explosion and, therefore, a release of energy. Combustion of fuel takes place in a controlled manner inside the combustion chamber. Combustion or burning of fuel anywhere else will cause a bang, which is called backfire.

Backfiring in lawnmower engines can be caused by either fuel-related causes or engine-related causes. Both are explained below.

Fuel-Related Issues:

Gas in the engine’s combustion chamber requires a certain amount of air to burn properly. Just like any burning, gas combustion requires oxygen. Each engine is designed so that the correct air-fuel mixture is provided to the combustion chamber during operation. All strokes are timed perfectly for the complete combustion of fuel, maximum energy release, and smooth machine operation. If the air-fuel mixture is in an incorrect proportion, it will cause all sorts of problems for the engine. For example, if the fuel is too rich, it could result in your engine blowing smoke.

The timing of all processes in the combustion chamber is vital. A process happening early or getting delayed even by some seconds can cause problems. An incorrectly proportioned air-fuel mixture can cause a timing disruption.

If there is too much air in the combustion chamber, the engine will not create a spark with enough power to ignite the fuel for some seconds. While the ignition is delayed, other combustion chamber processes keep happening in the way they are supposed to be. This causes the fuel to pool in the low spots along with the exhaust. This fuel can then get ignited outside the combustion chamber, producing an explosion that you know by the name backfire.

– Backfire Fix: Fuel related

An air-fuel mixture with more than the correct amount of air is known as low-pressure fuel. If your lawnmower is backfiring, it could be because low-pressure fuel is being pumped into its engine’s combustion chamber. Look for reasons for low-pressure fuel. Possible causes of low-pressure fuel include old fuel filters and failing fuel pumps.

Replace the old fuel filters and get the fuel pump repaired. If low-pressure fuel were the cause behind your mower backfiring, these fixes would solve the problem.

Engine Related Issues:

As mentioned above, the timing of all engine processes is very crucial for its smooth function. Engine-related issues that mess with the timing can cause backfire.

If your lawnmower is backfiring, check for its motor’s timing. If the motor timing is not right, the engine may ignite the fuel while the intake valves are still open. This can cause a backfire in the engine.

After prolonged use, the timing between the engine and the valve can become disrupted or out of the correct setting. This situation inside the engine results in backfires.

– Backfire Fix: Engine related

To solve the engine-related causes of backfires, take care of the following things.

• Engine Tune-up: An engine tune-up will restore the engine and the valves to the correct timing settings. Both valves will then open and close at the right time preventing the fuel from getting burned in the engine.
• Spark Plug: Clean or replace the spark plug. Clean the plug’s wires and the plug chamber. Doing this will ensure that the ignition occurs at the right time and will prevent the backfires that result from mistimed ignitions.
• Fuel Filter: Keep your mower’s fuel filter clean and replace it with a new one every year. Consult your mower’s user manual for more info in this regard.

Moving forward from the kind of issues that could cause engine backfires, let’s get into the details of when the engine backfires and what significance does the backfiring time hold.

During Starting:

Lawnmowers aren’t supposed to backfire when you are starting them. If your lawnmower backfires when you try to start it, it indicates that the mower is damaged somehow.

Many mowers have parts that serve to safeguard other more expensive parts. These inexpensive parts, such as the flywheel, sacrifice themselves to protect the expensive parts such as the crankshaft. If, during mowing, your mower runs over a large rock or its blades hit an obstruction, the flywheel breaks and won’t engage when starting again. This will cause your engine to stutter or backfire as you try to start it.

A mower with a broken flywheel won’t start normally, so it can’t be used until the flywheel is repaired. If your mower backfires when you try to start it, the indication is of damage. In this case, you must take your mower to a professional for repair.

During Shut-off:

Sometimes, when you mow, and you turn the engine off, or when your mower is idling, it will backfire. This is most probably happening because you are slowing your engine too fast.

The engine speed builds up during operation, and when you slow it down too quickly, it could pump gas to the mower’s muffler. This gas could ignite there and cause a backfire.

To reduce this kind of backfire, make sure that you gradually reduce speed and let the motor idle for 10 to 15 minutes before turning off the engine.

Another potential problem that could be the reason behind your mower backfiring when you try to shut it off is engine overheating. Engine overheating can be reduced by increasing airflow to the engine. If your mower backfires during shut-off and you suspect it could be because of engine overheating, take your mower to a professional or contact the manufacturer to learn ways of increasing airflow to the engine.

After Shut-off:

Sometimes, your mower backfires right after the engine is turned off. Backfiring that occurs after shut-off is caused by problems with the carburetor or muffler.

Get your carburetor checked for incorrect settings and your muffler for wrong construction. Getting these two components adjusted will solve the backfiring after the shut-off issue.

Using the wrong kind of gasoline can also cause after shut-off backfires. Gasoline that has alcohol ignites differently than gas that does not have alcohol. Gas with alcohol can get ignited in the muffler resulting in a backfire. Switching to gas with lower alcohol content or alcohol-less gas could solve the mower’s problem of backfiring after shut-off.

Does a backfire damage a lawnmower engine?

Generally, a backfire does not damage a lawnmower or another small engine machine. The explosion you hear is in the exhaust, and not in the engine. But when your lawnmower experiences a lot of backfires, it can damage the exhaust and engine over time. I always recommend fixing the backfire issue.

A lawnmower exhaust is not designed for backfire explosions, and the additional heat and strain can damage it over time. Depending on the reason for the backfire, also the engine can experience additional wear and tear. Resulting in a shorter life, and potentially engine failures.

Anti-backfire Equipment:

Special parts can be installed in some mowers to prevent them from backfiring after shut-off. Such features are called anti-after-fire solenoids. Installing them will let you turn off the mower’s engine at any speed without causing fuel to shoot to the muffler.

Installing anti-after-fire solenoids requires professional help. Take professional service if you want to equip your mower with such equipment.

Final Remarks:

Engine backfires sound dangerous, especially when they catch you off guard, almost every time there is a backfire. An explosion in the mower sounds crazy, but it is not something to worry too much about. The causes of engine backfires are mentioned in this article. Using this info, you can determine why your mower is backfiring and look for possible fixes. So, the next time your mower backfires, put the acquired knowledge to use and get the issue fixed before it causes permanent damage to your mower.