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Why is my Snowblower Backfiring? Reasons and Fixes


What to do when a snowblower is backfiring.

A snow blower is a must-have during the winter if you want to keep your driveway clear. However, they have one major disadvantage. When they’ve not been used for a long time, they tend to backfire when you start them up. This can be frustrating, especially if you have a ton of snow to get rid of.

A snowblower can have issues with backfiring due to issues such as spark plug degradation, muffler damage, and delayed engine timing. Identifying the root cause of backfiring will help to quickly resolve the issue.

You need to do is identify the root cause of the problem. This way, you can make an informed decision. We’ve explored some of the reasons why a snowblower can backfire and offered effective fixes for each. Let’s get this show on the road.

Problems with the Fuel System

If you’ve had gas sitting in the fuel system for a long time without using the snowblower, there’s a great chance the fuel system may be clogged. These devices’ fuel systems clog up easily due to old bad fuel. 

Not to mention, the high alcohol content in the gasoline can cause an oxidative process which further degrades the fuel system. Furthermore, if the carburetor is clogged and allowed to run lean, it can cause even more problems. 

How to Fix It

If you suspect your gasoline may be the reason why your snowblower is backfiring, there are several things you should do. These include:

  • Change the gasoline often: Make it a habit to change the gas in the device before it gets old and don’t let it sit in the fuel system for a long time.
  • Use a fuel stabilizer: These keep the fuel fresh and stable when it has to sit for a long time. Besides, they prevent chemical reactions and evaporation of volatile compounds which may cause ineffective ignition when you need to use the snowblower.
  • Use alcohol-free gasoline: It’s gentler on the engine and prevents harmful gas emissions.
  • Clean the carburetor: Use a carburetor cleaner to clear all the clogged-up material. 
  • Rebuild the carburetor: If cleaning doesn’t work, use a carburetor rebuild kit to get it functioning correctly once again.
  • Switch to an electric model: If you often have fuel trouble while using your snowblower, it’s advisable to consider an electric model. Since it uses electricity, you won’t have to deal with these fuel challenges even after you’ve stored it for a long time.

Spark Plug Degradation

If you’re using a weekend electrode or carbon has built up in the device, there’s also a high likelihood of your snowblower backfiring. If this is the case, the spark plug will degrade over time, thereby causing trouble with the ignition. You’ll either have improper ignition or none at all.

A good sign of spark plug degradation is the engine responding accordingly but the snowblower backfiring anyway. However, to be sure, there are several things you can do to troubleshoot the spark plug. These include:

  • Check the spark plug to ensure there’s no fuel that doesn’t belong there.
  • Ensure there’s a correct gap in the spark plug.
  • Check for any cracks in the porcelain parts of the spark plug.

How to Fix It

If you suspect that the spark plug may be defective, there are several things you can do depending on what the problem is. These include:

  • Remove fuel from the spark plug hole: If you noticed the spark plug is wet, this means some fuel that’s not supposed to be in this compartment has sipped in. If this is the case, take out the spark plug and turn the engine over several times until all the fuel is out. Next, clean the hole and spark plug and plug it back in. If the spark plug is impossible to clean, consider replacing it.
  • Correct the gap: If the spark plug is out of place, the gap may be causing the backfiring issue. To fix it, adjust the gap to its favorable position.
  • Replace the spark plug: If the porcelain parts of the spark plug have cracks, it’s time to replace it because it can’t be fixed.
  • Test the ignition coil: If the spark plug seems to be functioning okay, test the ignition coil because it may also cause similar problems. If there’s an issue, replace it.

Source: The Spruce

Poor Muffler Construction

Sometimes, the problem lies in the construction of the muffler. If the muffler is defective, the air control in the device will not be sufficient. Once the air is distributed into the poorly constructed muffler, the temperatures will soar higher and turn low because there’s insufficient air proportion.

As a result, this insufficient air proportion will clog up the system. It may also leave behind a significant amount of unburnt gasoline that may cause engine problems.

These problems may also arise if there’s a hole in the muffler. The hole may cause leakages that affect the overall performance of the snowblower.

How to Fix It

The only way to deal with issues with the muffler construction is to update the muffler equipment to a better design. This way, you’re guaranteed of better air control. Alternatively, you can opt to purchase a new snowblower with exceptional construction. This way, you’re certain you won’t have issues with performance.

Wrongly Adjusted Engine Speed

Your snowblower may also be backfiring because you’re adjusting the speed incorrectly. If you turn it to the low setting too fast, for instance, this can cause backfiring. By doing so, you’re not giving the engine enough time to cool down, and that’s why you’re experiencing the problems.

The Right Way to Do It

If the problem is your technique, the solution is quite easy. All you need to do is to ensure you’re gradually lowering the speed and not doing it all at once. This way, you’ll be giving the engine enough time to cool down before completely turning it off.

Delayed Engine Timing

If the engine’s ignition cycle doesn’t start correctly, you may also have backfiring issues because there will be an accumulation of unburnt fuel. Delayed timing causes the process to begin before the engine valve is fully opened, causing backfiring issues.

How to Fix It

To avoid trouble with delayed engine timing, the best solution is to maintain the electric system and speed to ensure consistent and correct engine timing. 

Source: Leading Gear

Starter Breakdown

If you’ve done everything and your snowblower is still backfiring, there might be an issue with your starter. This is a common problem in electric-start engines. The electric starters break down over time, thereby making it impossible to start the device.

How to Fix It

If the electric starter has broken, the only way to fix the problem is to replace it. It’s best to have it repaired by the manufacturer or someone who deals with your model. This way, you’re guaranteed that the replacement is not only compatible with your snowblower but of the best quality.

Nip the Problem in the Bud

It’s easy to assume you need a new snowblower when it keeps backfiring. However, as you have seen, in most cases, the problem requires a simple fix, especially if your snowblower has been in storage for a long time.  In such a case, the problem is often issues with the fuel system.

Therefore, before you decide to make another investment, consider the fixes above. And once you identify the issue, make sure you keep the device in tip-top condition for the next winter. The last thing you need is to face the same challenges every winter.

Teddy Henderson

Teddy is always fiddling with small engines, picking up thrown-out string trimmers or tearing apart dirt bikes. He shares what he learns along the way. Hopefully, you'll have less headaches than he has had by learning from his mistakes.

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