Why is my snowblower clogging or not throwing snow? Main Image

When winter weather unleashes its wrath we rely heavily on our arsenal of snow removal tools to bail us out. Many people who rely on snowblowers for their snow removal are familiar with the unit clogging up. Clearing snow is a demanding enough job, so who wants to extend the work by continually stopping to clear a clogged chute? Following these tips can help you reduce the likelihood of clogging your snowblower and find mechanical issues that may appear to be a clog.

NEVER Clear Snowblower Clogs with Your Hands!

It’s very important to never clear a clogged snowblower with your hands. An operator clearing a clogged snowblower or snowblower chute with their hands is the leading cause of snowblower injuries. According to the U.S. Consumer Product Safety Commission (CPSC), in a recent year there were 590 finger amputations involving snowblowers and, on average, there are an estimated 5,740 hospital emergency room-related injuries associated with snowblowers. When a snowblower gets clogged, the moving parts abruptly stop. This builds up and stores tension like a spring. They are designed to do this to prevent damaging the auger or engine when the auger or paddles are abruptly stopped. When the blockage is cleared this tension is released, causing the moving parts to continue moving again until the tension is fully released. Never use your hands to clear a clogged snowblower and make sure you’re following our snow removal and winter safety tips to help keep you safe while you combat winter’s icy wrath.

Common Causes of Clogs

Whether you’re using a single stage or two stage snowblower, there are some common causes of clogs that will stop up either type of machine. Whether it’s a hidden object, the type of snow being cleared or a mechanical problem, being aware of common issues can help you preventatively avoid clogging and differentiate a clog from a more serious mechanical problem.

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Tips from the mechanics:The most common causes of snowblower failure/clogging are related to fuel problems or hidden objects. If you notice you need to run your snowblower with the choke constantly engaged, this is a sign that you have a fuel issue and need to have it serviced.

The most common cause of chute clogging is running over a newspaper or other hidden object. It’s easy for some objects to become covered in a light layer of snow and become hidden in your drive or walk way… just waiting to ruin your day and leave you with a half-cleared driveway.

Hidden Objects

When a hidden object gets picked up and lodged into a snowblowers paddles or auger, it’s a guaranteed clog. A frozen newspaper or dog toy can end up costing you a few hours of frustration and, depending on the damage caused, can cost you a bit in repairs as well. We recommend making sure any areas you plan on clearing snow from are clear of all objects that can easily be hidden by snowfall and become lodged in your snowblower. Marking any walkways, driveways or planters with driveway markers will help you clearly see your boarders no matter how deep the snow is and will help you avoid accidentally hitting any landscaping materials used to edge your walkways and planters.

Wet, Heavy Snow

It doesn’t matter if you’re using a single or two stage snowblower when you’re fighting wet and heavy snow—clogs are likely. This is because wet, heavy snow, especially snow that’s been treated with de-icing material, is particularly sticky. When snow is partially melted, or “wet,” it packs together more readily and is likely to stick and freeze to other surfaces. When this starts to happen in your discharge chute; it gets clogged up. One way to reduce the effects of wet, heavy snow is to clear the snow early. When temperatures are lower, snow is lighter and drier. The earlier in the day you can get out to clear snow, the lower the temperature will be, and the sun will have melted less snow.

Many people recommend pre-treating your discharge chute with a variety of non-stick sprays, spray lubes or automotive and ski waxes. When these are applied to a dry discharge chute or impeller they will prevent snow from sticking to them. Many common recommendations are: PAM or a similar non-stick cooking spray, spray-on ski wax, Teflon or silicone spray lube and WD-40 or other penetrating oils. Using PAM or a similar cooking spray is friendlier to the environment than using WD-40 or other penetrating oils which don’t naturally biodegrade. Plus, most people have PAM or a similar cooking spray already in their pantry. Applying automotive or ski waxes to your chute may be a bit more complicated and time consuming, but according to some who put in the extra effort, the results tend to last longer than cooking sprays or penetrating oils and require fewer applications.

Too Much Snow Too Fast

Even if the snow is light and dry, taking on too much snow too fast will bog down your snowblower and can lead to clogging. Making sure you take on an appropriate amount of snow for the size and power rating of your machine is important to avoid clogging issues. After the first push down your driveway, it’s recommended to only clear half of the auger housing’s width with each push. This will help make sure you’re not taking on too much snow at one time. It’s also important to not let snow get too deep before deciding to clear it. The deeper snow gets, the heavier and more compacted it gets, making it harder to move. Removing less snow more frequently is a great way to avoid clogging and maximize your snowblower’s effectiveness.

Mechanical Issues

There are two types of snowblowers on the market: single stage and two stage snowblowers. Knowing how both of these systems work can help you identify more serious mechanical issues that could look like a clog.

Single Stage Snowblowers

These snowblowers are designed to grab the snow off the ground and throw it through the discharge chute in one step. The design of the scraper bar and paddles allows these snowblowers to function this way. They scrape down to the surface with the scraper bar, then the paddles follow through to grab the snow in front of the housing and throw it up and out of the discharge chute. Most models are even partially propelled by the paddles making contact with the surface as you push them. When these machines grab snow, the paddles dig down to the surface and grab everything. Because of this, they are more likely to grab heavy compacted snow while in use. This type of snow is harder to clear and is more likely to clog the machine. If you live in an area that regularly gets wet heavy snow, you may want to consider a more powerful two stage snowblower.

Paddles and Scraper bar

If you have a single stage unit, you’ll want monitor the gap between your paddles and the scraper bar. If the distance between these is too large, the snowblower will no longer throw the snow as far and can even start throwing the snow under or behind itself towards you. If you notice that you have to angle the machine forward more to get it to grab the snow, you should check the distance between your paddles and scraper bar. Some manufacturers will mark their paddles to indicate when it’s time to change them. As a good rule of thumb, the distance between the scraper bar and the paddles shouldn’t exceed a 1/2”. When the snowblower is turned off and the spark plug boot is disconnected, if you can fit your finger in between the paddle and the scraper bar—you need to replace them.

Single Stage Snowblower Belt Tension

If your snowblower stopped throwing snow but the engine is still running, there might be an issue with your belt. Make sure the machine is powered off and any clogs have been cleared with a clearing tool. Remove the spark plug boot and locate the side plate cover. This is the cover that protects the belt. If you’re facing the handlebar and controls as if you’re using them, it’s typically located on your left-hand side. Remove the side cover and inspect this belt. If it is loose or broken, this would cause your paddles to stop turning and throwing snow. When this belt starts showing signs of wear or starts to sag, it needs to be replaced.

Two Stage Snowblowers

Two stage snowblowers clear snow in two steps. They have a rotating auger that breaks down and chews up snow and ice in the front (step one) and an impeller located in the back of the auger housing which throws the snow up and out of the discharge chute (step two). When you push these, the scraper bar collects snow in the housing as you push it. Once the snow builds up enough, it hits the auger and is pushed into the impeller. Due to the size and weight of these units, they are equipped with skid shoes that allow it to skid across snow instead of dragging across bare surfaces. Due to the distance the skid shoes create between the surface and the scraper bar, two stage units don’t scrape as close to the surface. This means they don’t typically grab as much of the compacted snow from the surface and tend to clog less frequently.

Two Stage Snowblower Belt Tension

These units use two belts to power both the drive system and the auger system. The drive belt is located closest to the engine and the auger belt is located closest to the auger. If your snowblower suddenly stops moving, you feel it slipping or it seems to be moving slower than usual while in gear, you may have a drive belt issue. If your auger is engaged but stops when contacting snow or is throwing snow shorter distances than normal, then you may have an auger belt issue.

When experiencing these types of issues, while the unit is powered off and the spark plug boot is removed, locate and remove your belt cover. If either belt appears to be excessively worn or possibly snapped, you’ll need to replace that belt.

Shear Pins

The shear pins used in your snowblower attach the auger to the auger drive system and break when a blockage suddenly stops auger movement. If the auger engages but stops when in contact with snow, power off your machine. Make sure any clogs are removed with a clearing tool. If your auger spins freely by hand when powered off, you’ve likely broken your shear pins. Make sure you replace them with an exact replacement as specified in your owner’s manual. Using a standard bolt or a mismatched shear pin will cause them to not break when under stress and sudden jams could cause severe and costly damage to the auger, engine or any of the drive components.

Gear Box

The gear box in a two stage snowblower engages the auger belt and powers the auger. If you notice it pushing more snow than throwing, you may have a damaged transmission. Check the oil fill level of the gear box often. Making sure that this is adequately filled with oil will help you determine if there are any leaks. If you notice anything metallic in your oil , this is a sign that your gears are grinding or have been damaged. When this happens, it’s recommended to take apart and inspect the gear box to locate any damage. Depending on the severity, you may need to replace individual gears or the entire gear box.

Off-Season Maintenance

Making sure all the parts are able to move as fast as possible is one key aspect to making sure your snowblower clears the maximum amount of snow. Think about a merry-go-round: the faster it spins, the more centripetal motion there is to project things outward. Keeping these moving parts well lubricated through both the off-season and the current snow season will ensure that they are able to move with ease.

If you have a metal discharge chute or auger housing, make sure that there is no exposed or bare metal. This can lead to corrosion and may cause clogging. Make sure you re-paint any exposed metal to prevent corrosion.

When storing your snowblower for the off-season, add fuel stabilizer to the gas in the tank or run the fuel tank dry. Some people say using a fuel stabilizer is enough if you know your equipment will be sitting unused for extended time frames. This is not recommended with the prevalence of ethanol in gasoline and its effects on small engines over time. E10 gasoline degrades rapidly, as it does so it separates into layers of alcohol and fuel. The alcohol deteriorates the plastic and rubber components of the engine as it sits. Different manufacturers recommend different courses of action when storing equipment, but they all agree that you should never leave raw, unstabilized gas in a stored piece of equipment. If you plan on storing your snowblower for longer than two months, it's probably a good idea to make sure the tank is empty. Fresh gas is important in today’s world of ethanol infused gasoline. The longer it sits unused in a fuel tank or gas can, the more degrades rendering it more harmful to your engine the longer it sits.

Tips from the mechanics: Don't get stuck out in the cold with a partially cleared driveway! We recommend keeping commonly replaced parts for your snowblower on hand during the snow season. Once the snow starts flying, a lot of these parts start flying off the shelves. It's easier to acquire these parts while the demand is low during the off season instead of waiting for a back order while the snow starts piling up.

Being aware of common causes of snowblower clogs and common mechanical issues that can cause similar failures will help you know whether you need to turn to your clog removal tool and a can of PAM or your wrench set. Whether you’re removing a clog or troubleshooting a mechanical issue, NEVER reach your hand near the auger or paddles of an active, or powered on, snowblower. Taking preventative measures to avoid common causes of clogs and repairing mechanical issues as soon as you notice them will help you keep your snowblower moving steadily all season.