8 Reasons Your Snowmobile Runs on One Cylinder

A non-functioning snowmobile can be a nightmare. Running on one cylinder will markedly reduce performance and risk further damage to your engine.

Here are some of the reasons why your snowmobile runs on one cylinder 

  1. A problem with the sparks
  2. Problem with the fuel intake
  3. Snow build-up in the air filter 
  4. Worn-out piston rings 
  5. Problem with the head gasket 
  6. Cracked cylinder head 
  7. Overheating cylinder head 
  8. Bent valve 

You’ll want to avoid this issue, or quickly repair it if this problem pops up.

Why Do Snowmobiles Run on One Cylinder?

Snowmobiles run on one cylinder when there is an issue that needs fixing. In most cases, one of the cylinders might have a firing malfunction either because the spark plugs are not firing, or the ignition timing is faulty.

Regardless of the issue, the best thing to do is to fix it or have your snowmobile checked by a professional.

Let’s take a detailed look at the reasons why your snowmobile runs on one cylinder next.

1. A Problem With the Sparks

The spark plugs of your snowmobile fire up the cylinders and make them run. If there is any problem with the spark plugs, this may result in one of the cylinders not running. 

For instance, there could be a firing problem whereby the spark plug is not producing enough sparks to move the cylinder. Get a mechanic to rectify misfiring problems as soon as possible as they could affect the engine in the long run. 

Additionally, there could be a problem with the ignition timing. This is the timing of the spark relative to the position of the top dead center. If there is a problem with the spark plug affecting the ignition timing, it may result in one of the cylinders not working. 

You can learn more about ignition timing in this YouTube video:

If spark plugs are the reason for the non-functioning cylinder, it is best to buy new spark plugs. Besides, new spark plugs will also help avoid oil and gas leaks around the engine that mainly happen when one cylinder is not working. 

2. Problem With the Fuel Intake

There needs to be sufficient oil getting to each of the cylinders for them to function. To confirm if there is a problem with the fuel intake, pour some fuel on the malfunctioning cylinder then try to start the snowmobile. 

If this cylinder runs with fuel poured on it, it means that inadequate fuel is why the snowmobile runs on one cylinder. This would mean there is a problem with the fuel system or the fuel pump. 

Other signs that you may notice are the snowmobile losing power when you come to a stop, and in other cases, the engine may fail to start. Talk to your mechanic to know the real cause of the faulty fuel system and how to rectify it. 

3. Snow Build-Up in the Air Filter

Although the snowmobile was designed to operate in the snow, too much snow in the air filter could affect its operation. These air filters are meant to cool the engine and prevent dust and debris from getting to the engine.

Unfortunately, when snow clogs up in this air filter, it affects the carburetors jetting, causing an inadequate air-to-fuel ratio

An inadequate air-to-fuel ratio will cause one of the cylinders not to function properly. Moreover, the clogged air filter could also affect the combustion system and the engine’s functioning. It is advisable to check your air filter from time to time to confirm whether it is clogged. If air clogging is the reason for the non-functioning cylinder, you can rectify this by cleaning the air filter. 

To clean the air filter, carefully remove the filter, dip it in a high-flash-point solvent then rinse it to remove all the dirt, snow, and oil that may have accumulated. Later, mix a detergent with warm water, and use the detergent solution to ensure that you eliminate all debris. 

4. Worn Out Piston Rings 

Piston rings help regulate oil consumption and oil pressure. If these rings are broken or worn out, they have several adverse effects, and the non-functioning cylinder is one of them. 

Due to oil or gas leaks, worn out piston rings reduce compression on the cylinder, thus making it non-functional. 

If a broken piston ring is the culprit, you may also notice other signs like gray or white exhaust smoke, excess oil consumption, and poor performance. 

If you suspect that the piston rings have a problem, or notice any of these signs, perform a compression test on the engine. This test involves removing one of the spark plugs and starting the engine using a compression gauge attached to the cylinder. If the engine starts and the cylinder runs, you will need to replace the piston rings. 

Here is a YouTube video giving more details on performing a compression test. 

5. Problem With the Head Gasket

The purpose of the head gasket is to seal the cylinders firing pressure and prevent engine oil from leaking on the cylinders. Given its high connection with the cylinders, one cylinder may fail to function if there is a problem with the head gasket. 

Moreover, a worn-out head gasket may exhibit other signs like excess oil consumption, poor acceleration, and poor overall performance. The problem with the head gasket can be minor such as loose screws, bolts, or vents. These need simple fixes that you can do on your own. 

On the other hand, it can be a significant issue such as a break or leak, and in this case, you need to seek urgent mechanical help. 

6. Cracked Cylinder Head 

If your cylinder head is cracked, it may cause the overall cylinder not to function. If not addressed fast, it may cause more problems to the engine. In addition to having your snowmobile run on one cylinder, other signs of a cracked cylinder head are white smoke, rough running and misfiring, and combustion gasses in the cooling system. 

The leading cause of a cracked cylinder head is an overheating engine. If this is the problem with your cylinder, you should replace the cylinder head instead of repairing it to prevent further issues.

7. Overheating Cylinder Head 

Overheating of the cylinder head mainly happens when the radiator is full. When it overheats, it puts the cylinder under pressure and causes the components inside the combustion engine to overheat and distort their shape. 

This causes the cylinder to malfunction. Additionally, it can lead to engine failure, especially if not rectified fast. 

An overheating cylinder head can also lead to a cracked cylinder head. To prevent overheating, be careful with your snowmobile maintenance practices. Additionally, be cautious with your cooling system to ensure it functions properly and is not blocked. 

If you realize that overheating is the reason for your non-functioning cylinder, avoid pouring water on the radiator. Instead, visit a mechanic to find out the reason for the overheating cylinder head and rectify it.

8. Bent Valve 

Valves help control the movement of air in the snowmobile engine. 

Factors such as a broken timing valve, over-revving the engine, low engine oil, and an incorrectly timed engine can lead to a bent valve. A bent valve causes an imbalance of compression. This imbalance leads to low pressure in the combustion process causing fuel to burn incorrectly. 

Moreover, the bent valve causes a seal problem on the cylinder head, which affects the overall functioning of the cylinder.

Other signs that may show up in case of a bent valve are engine backfires, shaking engine, and excessive oil consumption. You can check whether you have a bent valve by removing the cylinder and checking if the valve is bent. 

Also, you can do a compression test to see how much compression the cylinder is producing.

I recommend using the BETOOLL HW0130 Petrol Engine Cylinder Compression Tester Kit (available on Amazon.com). It has an easy pressure release button and checks the pressure quickly and accurately. 

Sources

A non-functioning snowmobile can be a nightmare. For instance, you may realize that your snowmobile runs on one cylinder even when both the rear and the front cylinder are present. 

And you may wonder, ‘Why is my snowmobile running on one cylinder?’ 

Here are some of the reasons why your snowmobile runs on one cylinder 

  1. A problem with the sparks
  2. Problem with the fuel intake
  3. Snow build-up in the air filter 
  4. Worn-out piston rings 
  5. Problem with the head gasket 
  6. Cracked cylinder head 
  7. Overheating cylinder head 
  8. Bent valve 

Let’s expound on the reasons why your snowmobile is running on one cylinder and how you can get the non-functioning cylinder to run again. But first, 

Why Do Snowmobiles Run on One Cylinder?

Snowmobiles run on one cylinder when there is an issue that needs fixing. In most cases, one of the cylinders might have a firing malfunction either because the spark plugs are not firing, or the ignition timing is faulty.

Regardless of the issue, the best thing to do is to fix it or have your snowmobile checked by a professional.

Let’s take a detailed look at the reasons why your snowmobile runs on one cylinder next.

1. A Problem With the Sparks

The spark plugs of your snowmobile fire up the cylinders and make them run. If there is any problem with the spark plugs, this may result in one of the cylinders not running. 

For instance, there could be a firing problem whereby the spark plug is not producing enough sparks to move the cylinder. Get a mechanic to rectify misfiring problems as soon as possible as they could affect the engine in the long run. 

Additionally, there could be a problem with the ignition timing. This is the timing of the spark relative to the position of the top dead center. If there is a problem with the spark plug affecting the ignition timing, it may result in one of the cylinders not working. 

You can learn more about ignition timing in this YouTube video:

If spark plugs are the reason for the non-functioning cylinder, it is best to buy new spark plugs. Besides, new spark plugs will also help avoid oil and gas leaks around the engine that mainly happen when one cylinder is not working. 

2. Problem With the Fuel Intake

There needs to be sufficient oil getting to each of the cylinders for them to function. To confirm if there is a problem with the fuel intake, pour some fuel on the malfunctioning cylinder then try to start the snowmobile. 

If this cylinder runs with fuel poured on it, it means that inadequate fuel is why the snowmobile runs on one cylinder. This would mean there is a problem with the fuel system or the fuel pump. 

Other signs that you may notice are the snowmobile losing power when you come to a stop, and in other cases, the engine may fail to start. Talk to your mechanic to know the real cause of the faulty fuel system and how to rectify it. 

3. Snow Build-Up in the Air Filter

Although the snowmobile was designed to operate in the snow, too much snow in the air filter could affect its operation. These air filters are meant to cool the engine and prevent dust and debris from getting to the engine.

Unfortunately, when snow clogs up in this air filter, it affects the carburetors jetting, causing an inadequate air-to-fuel ratio

An inadequate air-to-fuel ratio will cause one of the cylinders not to function properly. Moreover, the clogged air filter could also affect the combustion system and the engine’s functioning. It is advisable to check your air filter from time to time to confirm whether it is clogged. If air clogging is the reason for the non-functioning cylinder, you can rectify this by cleaning the air filter. 

To clean the air filter, carefully remove the filter, dip it in a high-flash-point solvent then rinse it to remove all the dirt, snow, and oil that may have accumulated. Later, mix a detergent with warm water, and use the detergent solution to ensure that you eliminate all debris. 

4. Worn Out Piston Rings 

Piston rings help regulate oil consumption and oil pressure. If these rings are broken or worn out, they have several adverse effects, and the non-functioning cylinder is one of them. 

Due to oil or gas leaks, worn out piston rings reduce compression on the cylinder, thus making it non-functional. 

If a broken piston ring is the culprit, you may also notice other signs like gray or white exhaust smoke, excess oil consumption, and poor performance. 

If you suspect that the piston rings have a problem, or notice any of these signs, perform a compression test on the engine. This test involves removing one of the spark plugs and starting the engine using a compression gauge attached to the cylinder. If the engine starts and the cylinder runs, you will need to replace the piston rings. 

Here is a YouTube video giving more details on performing a compression test. 

5. Problem With the Head Gasket

The purpose of the head gasket is to seal the cylinders firing pressure and prevent engine oil from leaking on the cylinders. Given its high connection with the cylinders, one cylinder may fail to function if there is a problem with the head gasket. 

Moreover, a worn-out head gasket may exhibit other signs like excess oil consumption, poor acceleration, and poor overall performance. The problem with the head gasket can be minor such as loose screws, bolts, or vents. These need simple fixes that you can do on your own. 

On the other hand, it can be a significant issue such as a break or leak, and in this case, you need to seek urgent mechanical help. 

6. Cracked Cylinder Head 

If your cylinder head is cracked, it may cause the overall cylinder not to function. If not addressed fast, it may cause more problems to the engine. In addition to having your snowmobile run on one cylinder, other signs of a cracked cylinder head are white smoke, rough running and misfiring, and combustion gasses in the cooling system. 

The leading cause of a cracked cylinder head is an overheating engine. If this is the problem with your cylinder, you should replace the cylinder head instead of repairing it to prevent further issues.

7. Overheating Cylinder Head 

Overheating of the cylinder head mainly happens when the radiator is full. When it overheats, it puts the cylinder under pressure and causes the components inside the combustion engine to overheat and distort their shape. 

This causes the cylinder to malfunction. Additionally, it can lead to engine failure, especially if not rectified fast. 

An overheating cylinder head can also lead to a cracked cylinder head. To prevent overheating, be careful with your snowmobile maintenance practices. Additionally, be cautious with your cooling system to ensure it functions properly and is not blocked. 

If you realize that overheating is the reason for your non-functioning cylinder, avoid pouring water on the radiator. Instead, visit a mechanic to find out the reason for the overheating cylinder head and rectify it.

8. Bent Valve 

Valves help control the movement of air in the snowmobile engine. 

Factors such as a broken timing valve, over-revving the engine, low engine oil, and an incorrectly timed engine can lead to a bent valve. A bent valve causes an imbalance of compression. This imbalance leads to low pressure in the combustion process causing fuel to burn incorrectly. 

Moreover, the bent valve causes a seal problem on the cylinder head, which affects the overall functioning of the cylinder.

Other signs that may show up in case of a bent valve are engine backfires, shaking engine, and excessive oil consumption. You can check whether you have a bent valve by removing the cylinder and checking if the valve is bent. 

Also, you can do a compression test to see how much compression the cylinder is producing.

I recommend using the BETOOLL HW0130 Petrol Engine Cylinder Compression Tester Kit (available on Amazon.com). It has an easy pressure release button and checks the pressure quickly and accurately. 

Sources