While snowmobiles are fun, they can develop frustrating issues. One such problem is stalling, which can have multiple causes. Following a set of diagnostic and corrective actions can help get your snowmobile in good condition faster.
Here’s what to do if your snowmobile keeps stalling:
- Take note of all signs of snowmobile malfunction.
- Clean your snowmobile’s fuel tank.
- Clean your snowmobile’s carburetor.
- Clean the snowmobile’s air filter.
- Check your snowmobile for maladjusted screws.
- Check the snowmobile’s starter.
- Check your snowmobile for low compression.
Most stalling problems in snowmobiles arise in the carburetor or fuel system, but there are other culprits to consider. The rest of this article will explore possible causes of stalling in snowmobiles and their solutions to get your snowmobile up and running again.
1. Take Note of All Signs of Snowmobile Malfunction
Stalling is the main problem you are trying to solve. However, there may be other signs pointing to the underlying issue.
While diagnosing a stalling problem, it’s helpful to take note of all other unusual behavior displayed by your snowmobile. Such signs could point you to the primary source of the problem and considerably shorten the diagnostics and repair process.
However, this works best if you have experience dealing with snowmobile problems.
For example, an experienced person can tell that if the snowmobile stalls while reversing, it most likely has compression problems.
Still, even without experience, noting all unusual signs makes it easier to identify the cause of your problem.
2. Clean Your Snowmobile’s Fuel Tank
Fuel problems are a common cause of stalling in snowmobiles. Your snowmobile could be stalling because of a rich or lean fuel supply, usually caused by a faulty or dirty carburetor.
Before you clean the carb, you should clean the fuel tank.
If you have not used your snowmobile for a while, this step is essential as the fuel could have gone bad and could be the direct cause of your stalling issue.
To clean the tank:
- Detach it from the rest of the engine.
- Drain the fuel.
- Wash it thoroughly.
After it has dried, you can replace it, refuel, and check whether your stalling problem still exists. If it does, move on to cleaning the carburetor.
3. Clean Your Snowmobile’s Carburetor
Most stalling problems will come from issues in the carburetor. Before you start thinking of replacing parts or running the whole gamut of probable causes of stalling and their solutions, cleaning the carb is an excellent place to start.
One of the leading causes of a dirty carb is the prolonged use of contaminated fuel. This issue can cause the carb to gum up inside. If you store your snowmobile incorrectly, it can also cause carb problems.
When cleaning the carb, you can take one of two approaches:
- Use a carb cleaner if your carb isn’t too dirty.
- Take apart the carb and clean it manually if it’s filthy.
How To Clean the Carburetor With Carb Cleaner
While cleaning the carburetor with carb cleaner, you don’t have to take it out of your snowmobile and take it apart. The carb must stay connected to the engine as it will help boost the cleaning process (source).
Here are the steps to follow:
- Detach the engine hood to get access to the carb.
- Expose the carb by detaching the air filter.
- Take off the cover of the carb to expose its interior.
- Use about 3 seconds to spray the carb cleaner into the carb inlet.
- Start the engine to accelerate the action of the carb cleaner.
- Switch the engine off and replace the carb’s cover and the air filter.
Once you have completed the above procedure, check to see how your engine runs. Also, check whether you have resolved the stalling problem.
If the problem persists, you can move on to the more thorough and time-consuming method of cleaning the carb, which I will outline in the next section. You can also choose the comprehensive way just to be on the safe side.
However, if your carb isn’t very dirty, using a carb cleaner should work and might solve your stalling problem if the issue is the carb.
This Gumout Carb and Choke Cleaner from Amazon.com is one of the most effective carb cleaners. It’s manufactured specifically for the stalling issue in engines with dirty cabs. Apart from removing existing gum deposits in the carb, it also helps keep new deposits from forming.
How To Clean the Carburetor by Taking It Apart
Disconnecting the carb from the snowmobile and taking it apart will help you even clean areas that would typically be difficult to reach. If your stalling problem has anything to do with dirt in the carb, this cleaning method will solve the problem.
To take apart a snowmobile carb and clean it, follow the steps below:
- Detach the air filter, which will give you better access to the carb.
- Detach the fuel supply pipe.
- Undo the clamps that hold the carb to the engine, allowing you to lift the carb out.
- Detach the choke and throttle cables.
- Detach the carburetor float bowls.
- Use a screwdriver to take the pilot jet out.
- Use a nut driver to remove the main jet.
- Remove the float bowl’s seat assembly and needle.
- Detach the fuel screw and the jet needle.
- Gently scrub the removed parts with carb cleaner and a wire brush.
- Dry all the cleaned parts.
- Use high-pressure air to clean all the parts again.
- Restore the carburetor by replacing the components in the order you detached them.
Once you have cleaned the carb thoroughly and replaced it, run the engine. You might have messed up with the optimal setting of the idle screw. If so, adjust it to ensure that the engine idles appropriately.
Then, test to see whether your snowmobile is still stalling. If the problem was the carburetor, your snowmobile should have stopped stalling.
It’s essential to use high-pressure air in addition to scrubbing. In some cases, the carb will still have issues after scrubbing with carb cleaner but will become okay if thoroughly cleaned with pressurized air.
Also, while cleaning the carb, check the condition of components like plugs. If any part looks worn out to you, and you can easily replace it, consider doing so.
This step will have taken care of common stalling problems associated with the carb, including:
- Bad plugs.
- Dirt in the carb.
- Water in the carb.
- Dirty pilot jets.
If your snowmobile is still stalling after cleaning the carb and reinstalling it correctly, then the carb wasn’t the problem.
4. Clean Your Snowmobile’s Air Filter
For a snowmobile engine to run smoothly, the air, gas, and electricity must be at optimal levels. Air filters usually clog over time, and If the air filter is faulty or dirty, the air supply will be compromised, resulting in issues such as stalling.
How To Clean the Air Filter
Cleaning the air filter can save you a lot of trouble. You should do it periodically because a snowmobile can’t run properly with a clogged filter and air filters usually block with time.
Follow the steps below to clean your air filter:
- Carefully remove the filter from its frame.
- Soak the filter in a clean, high-flash-point solvent.
- Rinse the filter thoroughly to remove all the stuck oil.
- Squeeze the filter element to drain the solvent, ensuring you don’t harm the foam material.
- Rewash the filter in a mixture of warm water and a little detergent.
- Rinse the filter carefully.
- Dry the filter. Wrapping it in paper towels can help speed this step up.
Once the filter is dry, replace it. If cleaning the air filter didn’t solve the stalling problem, continue with the steps below.
5. Check Your Snowmobile for Maladjusted Screws
If your air-fuel mixture screw is maladjusted, the wrong ratio of air and fuel will get into the carburetor, which could cause stalling.
Similarly, if your idle screw isn’t adjusted well, your snowmobile will not be able to idle and will stall instead.
If your snowmobile is stalling, checking that these screws are appropriately adjusted is a critical step. If you set them incorrectly, correcting them could get your vehicle running correctly again.
To adjust a screw:
- Locate the screw.
- Loosen or tighten it.
- Start the engine to gauge the effect of the adjustment.
- Make adjustments until you are satisfied.
If the above steps don’t correct the stalling problem, move on to the other items in this article.
6. Check the Snowmobile’s Stator
The stator is responsible for igniting the fuel-air mixture in the engine so that it keeps burning. If the stator is faulty, the ignition will be faulty, and your snowmobile will experience problems such as stalling.
It’s relatively easy to check whether the stator is faulty and whether you should replace it.
How To Check a Snowmobile Stator for Damage
If your snowmobile is stalling, it might be because of a damaged stator. Checking whether your stator is faulty can help narrow down the issue.
Follow the steps below to determine the state of your stator:
- Remove the hood of the engine to access the motor.
- Open the motor housing to access the stator.
- Locate the stator and examine it for the following signs of damage:
- A missing wedge or block.
- A worn-out or swollen plate.
- Discolored winding.
- Cuts, burns, and bents.
- A crack in the powder coating.
If you spot any of the signs, you should replace your stator. If your stalling problem persists, check the rest of the items in this article.
7. Check Your Snowmobile for Low Compression
Faulty compression can cause stalling in snowmobiles. If your machine’s compression is below 120 psi, there’s an issue that you need to fix. Optimal compression should be about 120 psi.
One sign pointing to a low compression problem is the snowmobile stalling while reversing or the engine being difficult to start.
Compression problems are typically caused by a leak somewhere in the airflow system, for example, in the valves. You could have holes in the pistons or damaged piston rings.
To check whether you have a compression problem, perform a compression test using a compression gauge. Manufacturers of the Jifetor Engine Compression Tester (available on Amazon.com) have optimized this product for use with outboard snowmobile engines. With dedicated and universal adapters and a premium pressure tool set, this tester is easy to use, accurate, and easy to read.
How To Test Your Snowmobile Engine With a Compression Tester
Compression testing is the only way to diagnose a compression problem in your snowmobile engine. It lets you determine the pressure and compare it to optimal pressure values. If you have low compression, you’ve narrowed down your problem, which will be easier to solve.
Here are the steps to follow when performing a compression test for your snowmobile engine:
- Run the engine till it attains normal temperature, then stop it.
- Remove the spark plug wires.
- Remove the air filter.
- Disconnect the ignition system.
- Insert the tester’s adapter into the cylinder’s spark plug well.
- Wait for the pointer to stabilize before taking the pressure reading.
- Use the release valve to take the pressure to zero and repeat the test.
- The final reading for each cylinder should be the average of the two values.
The pressure should be equal in all cylinders. If it’s not, it could indicate the following problems:
- A faulty head gasket.
- Worn-out piston rings.
- A damaged crank seal.l
- Scored pistons or cylinders.
If your pressure is below 120 psi, then low compression could cause stalling in your snowmobile. You’ll need to find the source of the leak and seal it.
If your snowmobile keeps stalling, there are typical problems you should check, as explained in this article. Ideally, the signs of a malfunction should automatically narrow down the diagnostic or corrective steps you take.
However, your best bet is to go through all the possible problems and solutions like a checklist. In addition to the potential issues explored in this article, here are additional reasons why snowmobiles stall:
- Bad fuel
- Pinched fuel venting/ gas line
- Misadjusted oil cable
- Fuel pump problems.
Good luck getting your snowmobile back in tip-top shape!