Just like John Deere, Cub Cadet is one of the leading names in the lawn mower space and manufactures a long list of outdoor gardening tools.
However, just like any other machines, Cub Cadet lawnmowers aren’t perfect and are susceptible to myriad different problems related to the fuel tank, a faulty battery, safety switch, motor, clutch, ignition switch, mower engine, spark plug wires, bad spark plug, bad fuel pump, loose source of power and electrical connections, dirty carburetors and much more.
That said, I’ve compiled a list of Cub Cadet starting problems and fixes for you to explore. If any of these don’t solve your issue, I recommend getting in touch with a licensed Cub Cadet dealer.
1. Bad Fuel or Old Fuel
It may come as a surprise, but bad fuel or old fuel in the fuel lines or in the fuel tanks are the biggest reasons for a mower not starting. Gas can go stale and or lose its volatility in a short period of time like 30 days or so.
However, you can increase this storage length of time up to 24 months by using a product such as STA-BIL storage fuel stabilizer.
- Preserves Fuel - Keeps fuel fresh for up to 24 months so you can store the car you're not driving, keep outdoor power equipment fresh through the winter, or stock up on gasoline without worry
- Prevents Corrosion - Maintains a healthy fuel system by ensuring that your engine and fuel components don't suffer from the breakdown of ethanol or non-ethanol blended fuels
- Ensures Quick, Easy Starts - Helps you store any equipment or vehicle with confidence knowing that you'll be able to start it up smoothly without issue once you need it again!
Affiliate links and images pulled from the Amazon Product Advertising API on: 2023-12-09
There are several factors that contribute to how long gas will last including:
- Storage location
- Condition of the fuel container
- Wondering how long fuel can be stored for?
If your Cub Cadet mower is difficult to start, idles roughly, stalls out, or doesn’t start at all, you may have a case of “bad gas” – not the type that you have after dinner at your favorite Mexican restaurant.
First things first – it’s important to determine if the fuel in your mower is indeed old or bad, and is causing the issue of the Cub Cader mower not starting. I can usually tell if the fuel in my mower is bad or old via one of two ways:
- The smell test
- The appearance test
For the smell test:
- Move the mower to an open, even ground
- Remove the tank’s lid
- Smell the gas inside.
If the fuel has a strong, rotten, and sour odor, the fuel should be removed and replaced with fresh gas.
For the appearance test:
Bad fuel also looks a lot different than fresh gas, and you can check its appearance by removing it from the mower and pouring it into a transparent container.
For comparison, pour some fresh gas into another transparent container and set it beside the old fuel container. If the tank’s gas has a darker color than the gas in the fresh fuel container, it’s mostly likely old or has gone bad.
If the gas is bad, your only option is to remove it from the mower’s gas tank and replace it with fresh fuel.
How to Fix Bad Fuel or Old Fuel in Cub Cadet Mower?
You’ll need a few things to fix bad or old fuel in your Cub Cadet garden and lawn mower such as:
How to Fix Bad Fuel or Old Fuel in Cub Cadet Mower- Step by Step:
- Start by placing the mower in an area where its underside is easily accessible. Place it in a secure position to ensure it doesn’t tip. Tipping can cause the fuel to move to other parts of the mower such as the air filter and brake system.
- To avoid stains from messy spills, spread a tarp under the mower and follow safety precautions like wearing safety glasses and gloves.
- If the mower is dirty, remove the dirt from the surrounding areas of the fuel tank and remove the fuel tank lid.
- Use the siphon hose to drain the gas from the mower to the container, and check to see if all the gas is drained.
- Refill the gas tank and start the mower to see if it starts up and runs for a while. If the lawnmower runs for a while and shuts off, it could be a carburetor issue.
2. Clogged Cub Cadet Lawnmower Carburetor
The carburetor of your Cub Cadet lawnmower is designed to adjust the balance of air and fuel based on several factors such as:
- The type of terrain you’re crossing
- How long the engine has been running
- Your speed
The engine of your lawnmower carburetor will still run if the carburetor isn’t functioning properly but the mower may not run at all if the balance between the fuel and air is far off in either direction.
The carburetor of your Cub Cadet lawn mower works fine when it’s clean, so this task should be part of your regular lawnmower maintenance program.
The most common culprits when your Cub Cadet lawnmower won’t run are carburetor clogs and corrosion.
How to Fix Cub Cadet Clogged Carburetor?
Before attempting to fix a clogged Cub Cadet mower carburetor, it’s a good idea to check the air filter, because it’s responsible for ensuring no dirt or debris gets to the carburetor.
If the air filter is clean, then it’s time to remove the carburetor and inspect it more closely. Detach the carburetor from the Cub Cadet lawnmower and look for any loose dirt, excess dirt, or any signs of corrosion. See my guide on locating the carburetor on a lawn mower.
If you spot any corrosion, get a new carburetor. A Cub Cadet mower carburetor is fairly inexpensive and should cost anywhere between $10 and $30 depending on your mower model.
In terms of installation, you can either install the carburetor yourself (some technical expertise required) or at your local hardware store or Cub Cadet dealer.
If no corrosion is present, you can simply give the carburetor a good wipe-down with a product designed for carburetor maintenance such as the STA-BIL Carb/Choke and Parts Cleaner.
- Quickly cleans and dissolves gum, varnish, dirt, lead, and carbon deposits, aiding in faster starts and smooth idling
- Uses high grade formula to clean all unpainted metal parts, does not leave behind an oily residue after cleaning
- For gasoline, and diesel engines - Including: cars, trucks, motorcycles, tractors, buses, marine engines, lawnmowers, snowmobiles, snow blowers, construction equipment, etc.
Affiliate links and images pulled from the Amazon Product Advertising API on: 2023-12-09
3. Clogged Cub Cadet Air Filter
An air filter is an important component of a Cub Cadet mower and prevents dust and dirt from entering into the carburetor.
A clogged air filter simply means that it’s doing its job, but also doesn’t allow a sufficient amount of air to enter the carburetor, preventing the lawn mower from starting.
Cub Cadet says that the air filter should be cleaned or replaced every 50 working hours, and more frequently in dry, dusty conditions.
How to Clean Cub Cadet Air Filter?
- Stop the lawn mower engine, and wait for all moving parts to fully cool before handling.
- Locate the spark plug wire and disconnect it before removing the cover from the air filter.
- The air filter is protected by a shroud, which you can remove by undoing the screws or the clips.
- After removing the shroud, remove the air filter and inspect it. A Cub Cadet mower can be fitted with one of three types of air filters – a paper air filter, a foam air filter, or a hybrid air filter.
- If you have a paper air filter, simply tap it on a flat surface to remove any loose dirt. Replace the air filter if the paper of the air filter blocks a significant amount of light. For a foam air filter, check for signs of crumbling or telltale brown or yellow staining, which indicates that it’s time to replace it. For a hybrid air filter, refer to your owner’s manual for replacement procedures.
4. Faulty Cub Cadet Fuel Cap
The fuel cap of a Cub Cadet mower features a small vent, which when plugged prevents the mower from drawing fuel out of the fuel tank.
To check whether the gas cap is preventing the mower from starting, start the mower without the cap on, and if the mower starts, reinstall the cap when the mower is still running.
How to Fix Faulty Cub Cadet Fuel Cap?
Remove the fuel cap and inspect the vent for any dirt. Clean it with a damp cloth and reinstall it in the mower. If the fuel cap is damaged, replace it with a new fuel cap.
5. No Gas in the Tank
Speaking of fuel, if your gas tank is empty, your Cub Cadet mower isn’t going to start. You can check the level of gas in a lawn mower by unscrewing the fuel cap and checking to see if the level of gasoline is near the top. If it’s not, you may need to refill the tank.
How to Fix No Gas in Fuel Tank?
Before refilling the gas in the fuel tank of your Cub Cadet mower, you must choose the right type of gas, which is unleaded fuel that has an octane rating of 87 or higher.
You can also use regular fuel in your Cub Cadet mower as long as it doesn’t have an ethanol content greater than 10 percent.
See my guide on the best gas to use for your lawn mower.
Always buy fresh gasoline and use it within 30 days because it will start to degrade after this period. Adding to this, store unused fuel in a dry location to avoid moisture buildup or water from getting into the gas can.
6. Faulty or Damaged Spark Plug
Spark plugs are an essential component of a Cub Cadet mower and are designed to ignite the fuel-air mixture inside the cylinder of the mower engine. Here’s a detailed guide on small engine spark plug troubleshooting.
When the spark plugs get dirty or faulty, the quality of the spark decreases, resulting in incomplete fuel combustion and lower engine performance and efficiency.
The spark plugs of your Cub Cadet mower are located on the back side of your lawn mower engine. If you’re not sure where the spark plugs are located, refer to your owner’s manual.
How to Fix Faulty Cub Cadet Mower Spark Plugs?
Check to ensure that the spark plugs are connected securely to the mower because loose spark plugs will fail to ignite the engine.
If the spark plugs are dirty, you can clean them and reinstall them in the mower but I’d just replace them with new ones. Back in the day, spark plugs were expensive but today are available for roughly $10, making them a fairly inexpensive replacement.
If you notice that the spark plugs have carbon buildup or a cracked porcelain insulator, replace them with new ones.
Also, see my guide on when your lawn mower is not getting gas to the spark plugs.
7. Damaged Fuel Pump Can Prevent the Cub Cadet Mower from Starting
The fuel pump of your Cub Cadet mower pumps fuel from the tank to the carburetor. The fuel pump is susceptible to wear and tear and can fail after a period of use.
To identify a failing Cub Cadet mower fuel pump, check it for cracks or any fuel outside the pump.
How to Fix a Damage Fuel Pump?
The process of making sure the fuel is being pumped out of the fuel pump does require some technical expertise so it’s recommended that you get your mower looked at by a technician if you don’t know your way around. If the fuel pump has cracks or is damaged, it’s time for a replacement.
8. Faulty Battery or Lose Terminals can Cause Cub Mower to Not Start
Cub Cadet electric lawnmowers are fitted with a battery and a bad battery can prevent the mowers from starting.
First, check to ensure that the cables and battery terminals are secure, after which clean any corrosion that may have accumulated on the terminals using a baking soda solution.
Once you’re sure that you have a good battery connection, proceed to the next step of testing the battery voltage.
How to Fix Cub Cadet Faulty Battery?
You can test your Cub Cadet mower battery using a multimeter. Plug in the multimeter to the battery, and check the reading, which should be somewhere in the range of 12.7 volts for 12-volt batteries.
If it’s lower than this level, charge the battery and get it looked at by a technician if the battery won’t hold a charge.
9. Bad Ignition Switch
Cub Cadet electric lawn mowers are fitted with an ignition switch to fire up the mower, which if faulty or damaged will prevent the mower from starting.
Checking for a failed ignition switch is easy, where you simply turn the key in your Cub Cadet ignition to see if the mower starts.
How to Fix Cub Cadet Mower Ignition Switch?
There is no fix for a Cab Cadet mower ignition switch, and you’ll just have to replace the ignition if it’s bad. Cub Cadet ignition switches are available online, but make sure the one you buy is compatible with your mower model.
- HD⚡SWITCH: Engineered Performance
- ULTIMATE PROTECTION: Umbrella Key Protects Against Harmful Dust, Dirt and Water
- PREMIUM KEY: Protective Soft-Grip Umbrella Key
Affiliate links and images pulled from the Amazon Product Advertising API on: 2023-12-09
10. Bad Cub Cadet Ignition Coil
An ignition coil sometimes referred to as a starter coil is responsible for transferring voltage from the battery to the spark plugs.
If your Cub Cadet mower isn’t starting properly or fails to start, there’s a good chance there’s a problem with the ignition coil.
You can test the starter using an in-line spark tester to see if it can successfully produce a spark and if it does, you can rule out that there’s any problem with the ignition coil.
How to Fix Bad Cub Cadet Ignition Coil?
If a spark doesn’t appear in the spark window on the tester, the ignition coil is the cause of the Cub Cadet mower not starting. Fixing a Cub Cadet ignition coil does require some technical expertise but here are the steps if you’d like to give it a shot.
- The ignition coil is located in the Cub Cadet mower engine and is attached to the flywheel magnet.
- After removing the coil, diagnose it using a multimeter and compare the resistance.
- Buy a new ignition coil as recommended by the manufacturer and replace the old coil with the new one.
- If the ignition coil for your respective model isn’t available, get in touch with Cub Cadet customer care.
11. Damaged Recoil will Prevent a Cub Cadet Mower from Starting
The recoil starter assembly on a Cub Cadet mower allows you to start the combustion on the mower’s engine. This is a critical part of the mower, without which the mower won’t start.
The starter rope is the only visible part of the recoil starter system and sits either on the front handle or on the mower’s engine.
The starter rope can either break or can fall out of place, which can prevent it from retracting. Repairing the starter rope isn’t that difficult but does require removing the recoil starter assembly from the engine housing.
How to Fix Damaged Recoil on Cub Cadet Lawnmower?
- If the lawnmower has been running, wait for it to cool and disconnect the spark plug wire from the spark plug.
- Unscrew the three or four screws that hold the recoil assembly in place and remove the recoil assembly from the engine housing.
- You should now have access to the rope so pull it out and check to see if it’s broken, which will need to be replaced with a new one.
- If the rope is disengaged, refer to the owner’s manual on how to align the rope.
12. Blocked Fuel Lines in Cub Cadet Lawnmower
Just like the air filter and carburetor, the fuel lines of your Cub Cadet lawnmower can get clogged with dirt and debris.
When the fuel lines get clogged, gas will have a hard time flowing to the carburetor and the engine. To identify a clogged fuel line, you will need to inspect each section of the line to determine the blockage.
How to Fix Blocked Fuel Line in Cub Cadet Lawnmower?
- After you’ve identified the blockage in the fuel line, turn off the fuel supply, which is usually via a valve located at the bottom of the fuel tank. Some Cub Cadet mower models may not have a dedicated fuel shutoff valve, so use pinch pliers on the line to stop the fuel flow.
- Next, remove the clogged section of the fuel line,
- Spray carburetor cleaner into the line to loosen the blockage.
- Use a compressor to blow air through the line to remove the blockage, and repeat this process until the clog is removed.
- If you’re unable to remove the blockage, replace the line with a new fuel line.
13. Clogged Fuel Filter in Cub Cadet Mower
If you’ve ever had problems with your HVAC system in your home, the maintenance guy has probably already lectured you on changing the air filter regularly, and changing the fuel filter is just as important for the longevity of your Cub Cadet lawnmower.
Even though the fuel filter of your Cub Cadet mower is a small piece of equipment, it has a big job of preventing foreign materials like water and debris from entering the combustion chamber of your mower.
The fuel filter can be located in the fuel line or the fuel tank of a Cub Cadet mower and is designed to strain the impurities from the fuel before it enters the carburetor.
If the fuel filter is clogged, you may encounter small issues such as an annoying sputter when you start the lawnmower or in worse cases difficulty in getting the mower started or failure to start the mower at all. The fuel filter of a Cub Cadet mower should be replaced after every 200 hours of use.
How to Clear Clogged Fuel Filter in Cub Cadet Mower?
- Park the mower on even ground, and remove the fuel pump fuse.
- Disconnect the fuel lines and eject the filter.
- Clean the clogged filter with a good cleaner and reinstall it in the mower.
- If the fuel filter is damaged, replace it with a new one.
14. Bad Starter Solenoid
Most engines on Cub Cadet mowers use an electric starter system, and a wire solenoid is an important part of this system. A bad solenoid can prevent electricity from getting to the starter motor and prevent engine startup.
How to Fix Faulty Solenoid Issue in Cub Cadet Mower?
If you have any outdoor power equipment including lawnmowers with a faulty solenoid, get it looked at by a professional Cub Cadet technician.
15. Incorrect Operating Procedures
Cub Cadet manufactures a wide range of mowers, and the startup procedures for each model may vary, such as stepping on the brake pedal and adjusting the choke.
Refer to your owner’s manual on the right startup procedure for your Cub Cadet lawnmower model.
16. Battery not Charged
If you have a Cub Cadet cordless lawnmower, make sure the battery is charged before operation because a low battery can prevent the mower from starting.
Mowers are just like any other machine and can run into several problems after a period of use. I’ve listed all common Cub Cadet mower problems and fixes. But if you’re still having trouble, contact an authorized Cub Cadet dealer.
Hi, Alex Kuritz here. Growing up I remember that my family had one of the best lawns in the neighborhood. Richly green and lush. I did a lot as I grew up in terms of caring and tending for not only my family’s lawn but also my neighbors. I can say I have years of experience, and I am here to share it with you.