Yamaha Grizzly Won’t Start? (Troubleshooting and fixes)


Yamaha’s ATVs are renowned for their superior quality and build. However, this doesn’t mean they don’t have their fair share of issues. Yamaha Grizzly’s problems with starting are the best example of that.

Yamaha Grizzly ATVs won’t start when there is a faulty spark plug. The problem is easy to diagnose and it doesn’t cost too much to fix. You can tell if an ATV spark plug is faulty if it has carbon residue buildup at the end. Other common reasons why Yamaha Grizzlies have problems starting are weak battery, bad starter, and engine timing among others.

As you can see, the reason why your Yamaha Grizzly won’t start can be one of many. This might seem overwhelming, but I show you how to troubleshoot and fix the problem that’s causing problems to your four-wheeler.

How to Troubleshoot Yamaha Grizzly Start Issues

Camo Yamaha Grizzly ATV facing forwards

Over the years, the Yamaha Grizzly has been one of the most loved models of ATVs in the world. The main reason why is because Yamahas are reliable, powerful, and durable. Even though these machines do not face as many problems as other quads, this doesn’t mean that they are flawless. There are some issues that you still need to deal with. The most common one is not being able to start. Luckily, this problem can be troubleshooted and fixed ASAP. Here is what you need to do:

#1 Spark Plug

If you ask anyone who has been riding ATVs for a long time what is the most common reason Yamaha ATV’s won’t start, the answer will most likely be a faulty spark plug. Even though spark plugs are supposed to be changed every 100 hours or a few thousand miles, they often go bad before their time.

To check if this is your situation as well, take out the spark plug and examine it visually first. If you notice carbon residue buildup at the end of your plug, then this is a clear indication you need to change it. The good news is that this is a cheap and easy change to make.

In case the spark plug looks fine, then it’s time to test the spark. Connect it to the spark plug wire and place it on anything made of metal such as the cylinder. Start the engine and see if the plug produces a spark. If not, then it’s time to change it. The same goes if the spark is weak and orange, rather than a vibrant blue spark. You can read my ATV spark plug guide to learn more.

#2 Battery

The battery is like the heart of your ATV. It provides the necessary electric charge to start the engine and power other electrical components. A drained battery can be the simplest reason your Grizzly refuses to start. Always ensure your battery is fully charged, especially if the ATV has been sitting idle for a while.

You can use a multimeter to measure the battery’s voltage and see if it’s drained. A reading below 12V means the battery is weak and needs to be fully charged or replaced. My ATV battery voltage guide can help you here.

#3 Starter Solenoid Issues

The starter solenoid acts as a bridge between the battery and the starter motor. When you turn the ignition, the solenoid engages, allowing electricity to flow from the battery to the starter, which then cranks the engine. A malfunctioning solenoid can impede this process.

During your power supply check, extend your inspection to the starter solenoid. If the battery reading was correct but the solenoid’s wasn’t, the solenoid could be the culprit. Checking the solenoid’s connections and ensuring they’re free from corrosion can sometimes solve the problem.

#4 Carburetor

The carburetor is responsible for mixing the right amount of air and fuel, delivering it to the engine for combustion. An imbalance or obstruction can lead to starting issues. A common problem with Grizzlies is a stuck float, which can prevent fuel from flowing correctly. This usually makes the ATV to keep stalling despite giving it constant fuel.

If your ATV momentarily starts but then stops, it could be a stuck float in the carburetor. Gently tapping the carb can sometimes release the float. Additionally, ensure that there’s nothing blocking the fuel line. Using an air compressor can help identify and possibly clear any obstructions.

#5 Fuel and Air Filters

The fuel and air filters protect the engine by trapping dirt, debris, and other contaminants, preventing them from entering the engine. Over time, these filters can become clogged, restricting the flow of air or fuel, leading to performance issues or even preventing the ATV from starting.

Inspect both filters for signs of excessive dirt or damage. A severely dirty air filter might be beyond cleaning and require replacement. The fuel filter, if clogged, can impede the flow of fuel to the engine, leading to starting problems. Ensure regular maintenance checks and timely replacements to keep your ATV in optimal shape. I should also mention that cleaning your fuel and ATV filters is an essential maintenance quad routine.

#6 Bad Engine Timing

Engine timing is crucial for the efficient operation of an ATV. It ensures that the engine’s valves open and close at the correct times during each cylinder’s intake and exhaust strokes. Incorrect timing can lead to poor performance or even prevent the engine from starting.

Diagnosing a timing issue can be complex and might require specialized equipment. I have a guide that shows how to fix ATV timing. You should check it out because it might be what gets your Yamaha Grizzly starting normally once again. Regular maintenance checks and ensuring the timing belt or chain is in good condition can help prevent such issues.

Is It Safe To Push Start a Yamaha Grizzly?

In case your Yamaha Grizzly ATV stops starting and there is an emergency, such as being stuck on the trail, you can push start it. This method is usually for ATVs with dead batteries, but you can also use it for four-wheelers that just won’t start to force them. However, it’s essential to be careful when it comes to Grizzly ATVs because they are big, thus making the process more challenging and potentially riskier.

Nonetheless, if you are in a situation where push starting is your only option, it’s safe to do it. Just make sure that you know how to push start an ATV and that you choose to do it on a downhill slope. If you don’t know how to push start an ATV, just keep on reading because I will show you how.

How to Push Start an ATV

  1. Prepare the ATV: Ensure the ignition is turned on and the gear is in neutral.
  2. Check the surroundings: Check to see that there are no obstacles in your path and the terrain is suitable. Ideally, a slight downhill slope can make things easier.
  3. Positioning: If you have an assistant, one should be on the ATV while the other prepares to push. If alone, you’ll need to push the ATV yourself.
  4. Pushing: Begin pushing the ATV to build momentum. If you have someone to help, once you’ve built a steady pace, signal to them to drop the ATV into second gear.
  5. Engage the clutch: The person on the ATV should hold the clutch lever in (if your ATV has one), allowing the wheels to turn without engaging the engine.
  6. Drop it into gear: Once you’ve built sufficient momentum, quickly release the clutch. This should turn over the engine, causing it to start. If it doesn’t catch immediately, pull the clutch in again, push for more momentum, and try once more.
  7. Ride On: Once started, the rider should give the ATV a little throttle to ensure it doesn’t stall. From here, operate as usual.

Remember, while this method can be a quick fix in certain situations, it’s essential to fix the problem that’s causing the ATV to not start, whether it’s a dead battery or another problem, to prevent future inconveniences.

Bob Kelly

Hey there, my name is Bob and I've been riding ATVs, dirt bikes, and UTVs for most of my life. Going on outdoor adventures has always been my passion. I love sharing tips and tricks with beginners who are getting ready to join the world of outdoor enthusiasts. You can reach me at bobtheatvguy@gmail.com if you want to get in touch.

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