A snowmobile won’t spark if the electrical system isn’t functioning correctly. The electrical system includes the battery, alternator, ignition coils, spark plugs, and wiring. If any of these parts are damaged or worn out, the snowmobile’s engine will not start.

This article explores some of the most common reasons why a snowmobile loses spark and what you can do to fix and prevent it.

How Do You Fix a Snowmobile Without Spark?

Sparking is an essential part of the combustion process that allows your snowmobile to run. Without the spark, the fuel and air mixture in the engine will not ignite, and the snowmachine, as Alaskans call it, won’t start.

Here are seven things to look out for if your snowmobile has no spark, plus their fixes:

1. Dead Battery

One of the most common reasons for a snowmobile not to spark is a dead battery. The battery provides power to the ignition system, which it can’t do if dead.

To test the voltage across the battery terminals, use a voltmeter. If the voltage reading is less than 12 volts, the battery is discharged and may need replacing.

Recharge or Replace the Battery

You may get your battery back to a working state by jump-starting it with a booster pack, then driving your snowmobile to allow the alternator to recharge the battery.

If the battery discharges below 10.5 volts, its plates are likely covered with lead sulfates. If the battery is left dead for a lengthened period, these sulfate crystals harden to the point normal recharging cannot break them. In this case, you’ll likely have to get a new battery.

2. Faulty Ignition Coil

If an ignition coil is not working correctly, your snowmobile’s engine will not spark. Ignition coils transform the electrical energy from the battery into the high voltage needed to produce a spark at the spark plugs. So if one ignition coil isn’t working, the spark plugs won’t fire.

To test your snowmobile’s ignition coil, use an ohmmeter to measure the resistance across each terminal. Resistance is measured in ohms and denoted by the Greek letter omega (Ω). If the reading isn’t within the manufacturer’s specified range, the ignition coil is faulty.

Replace the Ignition Coil

You cannot repair a bad ignition coil—the only solution is to replace it. Replacing an ignition coil is a relatively easy and inexpensive process. Here’s a YouTube video by Ripping & Wrenching showing how to change a coil pack on a 1994 Arctic Cat Puma 340:

3. Worn or Failing Spark Plugs

Worn spark plugs could be the reason why your snowmobile won’t start. These small parts are responsible for creating the spark that ignites the fuel in your engine. If they’re failing, combustion in the engine won’t start, and you’ll have difficulty starting the snowmobile.

To inspect the spark plugs, take them out of the snowmobile using a socket wrench and a spark plug socket. Some of the signs of bad spark plugs include rounded electrodes, carbon fouling, and erosion or corrosion.

Replace the Spark Plugs

Replacing worn spark plugs can prevent costly damage in the long run. You can pick up spark plugs at most snowmobile dealerships or auto parts stores. Be sure the plugs you purchase fit your snowmobile model, as the wrong spark plugs can damage your engine. If you’re unsure of which ones to get, ask a professional for help.

4. Engine Oil Leaks

The presence of oil on your spark plugs can prevent sparking, therefore preventing the engine from starting. Oil can leak onto the spark plugs due to a bad oil seal, blown head gasket, bad connections, among other reasons. In extreme cases, oil-fouled spark plugs can trigger an engine fire, so it’s crucial to address the problem immediately.

Fix the Oil Leak

Cleaning the spark plug will not fix the problem because the oil will just come back. For a long-lasting solution, find the cause of the leak and fix it yourself or take your snowmobile to the mechanic. If the latter, be ready for a hefty repair bill.

5. Overheating Engine

An overheating engine can erode the spark plugs, causing sparking problems. Various reasons can cause your snowmobile’s engine to overheat, such as radiator issues, low oil levels, a broken water pump, and coolant leak.

Fix the Cause of the Overheating

Replacing the spark plugs, in this case, will only be a temporary fix if the engine continues to overheat. To fix the issue for good, find the cause of the overheating and fix it. When troubleshooting an overheating engine, a great place to start is your fluid levels.

Check the oil and the coolant levels. If either is low, say the engine oil, top it up to the correct level. If it disappears again, you have a problem—the most obvious being a leak in the system. 

Restricted airflow through the radiator can also be the culprit. Removing dust, dirt, and debris that has accumulated on the outside of the radiator will restore proper airflow.

6. Bad Stator

The stator generates power for the spark plugs and all other electronics. So if your snowmobile isn’t starting, it could indicate the stator is failing.

Rebuild or Replace the Stator

If you pinpoint the stator as the cause of a weak spark or no spark, you can rebuild it or replace it. You can do both yourself or hire a mechanic. The former will require patience, some mechanical skills and knowledge, and a decent set of tools—but it will save you money.

7. Wiring Harness Failure

A wiring harness failure can be another reason behind your snowmobile not sparking. A wiring harness houses the cables that contain the wires that transmit signals or electrical power from the battery to the ignition coils and spark plugs.

If the harness is damaged and exposes the wires, this can interfere with their ability to supply the power needed to start the snowmobile.

Replace or Repair the Wiring Harness

To determine if the wiring harness is damaged, check for any visual damage—look for signs of melting, cracking, or other wear and tear.

If a small section of the wiring harness is damaged, you can repair it by adding overlay wiring over the damaged area. If there’s extensive damage, the harness requires replacement.

How To Prevent Spark Loss in Your Snowmobile

The most effective way to prevent a sparking issue is to maintain your snowmobile regularly.

An oil change is an excellent place to start. It keeps all moving parts of your engine lubricated, preventing overheating. It also reduces or removes dirt and debris that can build up, ensuring the engine runs smoothly.

Replacing your snowmobile’s air filter is another preventative tip. Doing so ensures clean and unrestricted airflow to the engine, which helps prevent an air-fuel imbalance that can foul the spark plugs, causing loss of spark. A clogged air filter can also cause decreased performance and reduced fuel efficiency.

Spark plugs are crucial to your snowmobile’s ability to spark. So for the final tip—change them out every season—it will help keep your engine healthy. If you ride often, you might want to replace them more frequently.

Final Thoughts

If your snowmobile has no spark, it’s crucial to find and fix the source of the problem. This can be any number of things, including a bad ignition coil, a wiring harness failure, or a worn spark plug.

If you decide to diagnose and fix the snowmobile yourself, ensure to consult the factory service manual for the repair specifications for the repair you’re attempting. If you’re having difficulty troubleshooting or fixing the problem yourself, you can always have a mechanic take a look. 

Regular maintenance can help prevent your snowmobile from failing to spark.

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