A snowblower that keeps stalling isn’t going to help you get the job done. The are many reasons that can keep you from clearing snow from your driveway. You don’t want to be stuck in the cold longer than you have to, so let me help you determine why your snowblower keeps shutting off.
A Cub Cadet Snowblower may keep stalling when the fuel is old, the choke setting is incorrect, the fuel line is clogged, the carburetor is dirty, the spark plug is bad, the engine oil level is high or the gas cap is bad.
Always take caution when working on your snowblower. This includes removing the spark plug prior to performing any repairs. Never place your arms or legs near the auger or chute areas. Follow additional safety measures as outlined in the Cub Cadet operators manual.
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Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
7 Reasons a Cub Cadet Snowblower Stalls
Old gas can play a big role in why a Cub Cadet snowblower keeps stalling. Gas doesn’t last long before it begins to break down and become less effective. You should actually consume your fuel within 30 days of purchase.
Much of today’s gas includes ethanol, a plant-based alternative fuel used to make gas more environmentally friendly. Ethanol, while okay to run in most vehicles, is not good for the small engine on your Cub Cadet.
Ethanol attracts moisture to the fuel system. Moisture and ethanol in the fuel system will eventually leave behind varnish and gummy deposits.
These deposits may cause fuel restrictions resulting in an insufficient flow of fuel to the engine causing it to run sluggishly or stall.
To minimize the negative effects ethanol will have on your snowblower, only use gasoline with a minimum octane rating of 87 and a maximum ethanol content of 10%.
A low ethanol content or ethanol-free fuel is best. Read more about gas for a Cub Cadet snowblower here.
Gas for 2-cycle and 4-cycle Cub Cadet snowblower engines
- 2-cycle engines have a single fill port for a gas and oil mix. You can find the correct gas and oil ratio for your engine listed on the original fuel cap or in your operator’s manual.
Cub Cadet 2-cycle snowblower engines require a gas-to-oil mix at a ratio of 50:1. Mix gas with a premium 2-cycle oil that is ISO-L-EGD and JASO M345 FD certified
- 4-cycle engines have separate fill ports for gas and oil, one fill port for gas, and one for oil. It uses straight gasoline in the fuel port.
When you are running into problems with your Cub Cadet stalling and you find the fuel is old, first remove old fuel using a fuel siphon pump before you begin checking the other components.
Fill the fuel tank with fresh fuel and a fuel additive like Sea Foam Motor Treatment or STA-BIL to reduce moisture, clean the fuel system and stabilize the fuel. Read more about why I use fuel additives in my snowblower here.
Incorrect Choke Setting
To start a cold engine, the engine requires additional gas and less air to start. The choke is engaged to restrict airflow to allow a higher concentration of fuel.
Once the engine has warmed, the choke must be adjusted to the off position so the engine gets sufficient air to keep running.
Clogged Fuel Line
The fuel line on the Cub Cadet snowblower can become clogged with gummy deposits left behind by old fuel. When this happens, there is a lack of sufficient fuel flow causing the engine to run sluggishly and stall.
Use your fuel shut-off valve to stop the flow while you remove an end of the fuel line and place it in a container to collect fuel. Turn your fuel supply back on and check the container to see if you are getting a good flow of fuel out of the line.
If you are, turn off your fuel supply and reattach the fuel line. If you are not, with your fuel supply turned off, remove the section of the fuel line from your snowblower. Spray carburetor cleaner into the line to help loosen the clog.
Then blow compressed air through the line to try to remove the clog. Repeat as necessary until the restriction is removed.
If you are unable to remove the clog or you find the fuel line is dry and cracked, replace it with a new fuel line of the same length and diameter. Install the cleaned line or new replacement fuel line.
A dirty snowblower carburetor can be the cause of your snowblower not running and continuing to stall. The carburetor is designed to regulate the amount of gas mixed with air to create combustion.
When the carburetor gums up and clogs the fuel jet or causes parts to stick, your carburetor is no longer able to mix the correct gas to air mixture. Insufficient fuel supply can cause the engine to stall.
You will need to check and clean your carburetor if necessary. This may sound complicated, but it really is not. If you don’t want to attempt to clean it yourself, a small engine mechanic can do it for you.
12 Steps to Clean Your Dirty Cub Cadet Snowblower Carburetor
- Spray carb cleaner to minimize carbon buildup. Spray some carb cleaner in the air intake. Start the engine to see if it will run. If the snowblower fires up and still won’t stay running, then we need to get inside the carburetor.
- Gather pliers, screwdrivers, sockets, and ratchets so you don’t destroy parts while taking the carburetor apart.
- Take a photo for reassembly. These days most people have a handy camera on their phones. It’s a very good idea to take a picture of the carburetor so you can refer to it if you don’t remember how to reassemble it after tearing it apart. You will want to make sure you get a photo showing how the linkage and springs go back on the carburetor.
- Remove the throttle cable and choke cable if your snowblower has one.
- Slowly remove the springs so you don’t stretch them out too much. You may have to twist the carb a bit to get the springs off. Also, watch the gasket at this point so you don’t tear it. This is the gasket located between the engine block and the carburetor.
- Remove the bottom screw from the float bowl. The float bowl is where gasoline is stored inside the carburetor. It should have gas in it so have a rag ready to catch the gas.
- Remove the bowl being careful to not damage the o-ring around it. Caution: Do not get any carb cleaner or any other chemical on the o-ring. It will stretch out and you won’t be able to reuse it.
- Inspect the stem for clogged holes. This stem hangs down from the center of the carburetor and has holes in it. If these holes get plugged from old fuel it will not draw fuel up to the jet. If the holds are plugged, take a thick wire to clean them out. It’s easier to see what you’re doing if you use a flashlight. Once you get the holes clean you can rinse them with carburetor cleaner.
- Inspect the carburetor for hard crusty white buildup. This white buildup is fuel additives including ethanol. You need to try to get as much of the white power material out as you can. It’s nearly impossible to get it all out.
- Reassemble the carburetor now that the carb is clean. Put it back together in the reverse order you took it apart. Remember to refer to the photo you took of the carburetor when reassembling so all parts are reinstalled in the right places.
- Add new fuel that contains and fuel stabilizer before you start your snowblower. Pour the fuel into the tank and give it a chance to fill the bowl of the carburetor. Start your engine. If you are starting with a pull cord, give the rope a yank. It may not start on the first pull, but it should start after several pulls and continue to run.
Bad Spark Plug
Not only will a bad spark plug cause the snowblower to keep stalling, but also an incorrect electrode gap or a loose spark plug wire will cause this problem.
A fouled spark plug will cause intermittent spark issues that can cause the snowblower to quit. Remove the spark plug and check to see if it is dirty and covered in carbon buildup or oil. Clean a dirty spark plug with a wire brush.
If the spark plug appears very dark in color or damaged, you must replace it with a new spark plug. Before installing the plug, make sure it has the correct gap.
Too Much Engine Oil
Running a 4-cycle snowblower with too much oil in the crankcase can cause oil to get up to the spark plug and foul out the plug. This will inhibit the spark needed to run the snowblower.
It can also cause your engine to hydro lock. Read more about the effects of using too much oil in your snowblower in “Too Much Oil in Your Snowblower Can Cause Engine Damage“.
Correct the engine oil level by draining a little oil from your 4-stage engine. Check your spark plug and replace it if it is dirty or covered in oil.
Bad Gas Cap
The gas cap on a Cub Cadet snowblower is designed with a vent to allow air to pass through the cap. When the vent is plugged, the fuel tank forms a vacuum. It won’t allow fuel to leave the fuel tank and your snowblower will stall and die.
To identify a bad gas cap, remove the cap and start the snowblower. If it starts and runs well, reinstall the gas cap and continue to allow the snowblower to run for a while.
What you’re trying to do now is see if the same issue develops. Listen for the engine to start running sluggish and then shut down due to a lack of fuel.
If it doesn’t start and run smoothly until you remove the gas cap to allow air to flow into the fuel tank, you most likely have a bad cap. You should replace the bad cap with a new one.
Cub Cadet Snowblower Stalling Problems (Quick Reference Chart)
|Old gasoline||Drain old fuel and fill it with fresh fuel. Use a fuel additive to reduce moisture and clean the fuel system.|
|Incorrect choke setting||Engage the choke to start a cold engine and remove the choke when the engine is warm so it continues to run and won’t stall.|
|Clogged fuel line||Stop fuel flow and remove the fuel line from the snowblower. Use carburetor cleaner and compressed air to remove the clog.|
|Dirty carburetor||Remove and disassemble the carburetor to clean it. Rebuild the carburetor or replace it when internal parts are not working as designed.|
|Bad spark plug||Clean a dirty spark plug. Replace a spark plug that is very dark in color, is damaged, or has a burnt electrode.|
|Too much engine oil||Check the engine oil and remove a little oil until it reaches the full level line on the dipstick.|
|Bad fuel cap||Replace a gas cap when it no longer allows air to pass through the cap allowing the fuel tank to vent.|