Four-Wheeler Turns Over but Won’t Start: How to Fix It

Table of contents:

Fuel Supply Battery Spark Plugs Carburetor Air Filter Compression

10 January 2023

One of your responsibilities as a four-wheeler owner is to repair issues when they occur. Often, some of these issues are what you can fix on your own. A four-wheeler that turns over but won’t start is one of them.

When you turn on your four-wheeler, but the engine fails to start, you are frustrated and disappointed. You don’t even know where to begin.

But don’t fret. When your 4-wheeler turns over but won’t start, there are a few quick checks you can carry out.

Fuel Supply

Even as a beginner, checking the fuel supply is the first thing that comes to mind when your ATV turns over but won’t start. Is the engine getting enough fuel supply? The engine requires fuel, and lack of fuel is a common reason ATVs don’t start even when they turn over.

Battery

Another important area to check is the battery. Check if the battery is in good condition and has enough charge. One way to know if the battery is charged enough to power your quad is to use a multimeter.

Place the leads of the multimeter on the battery terminals. The reading you get informs you if the battery is charged or not. If the battery reads above 12V, you can move on to the next check. However, if the reading is below 12V, you need to charge the battery.

And if the battery still gives a low reading after charging for a long period, then replace the battery and check again.

Spark Plugs

Even when your ATV turns over and has enough fuel and a good battery, it won’t start due to lack of spark. The engine needs enough spark to ignite the fuel for combustion. But this is what you can fix on your own too.

Since your spark plug supplies spark to begin the combustion process, you want to examine the spark plug. Start by removing the spark plug from the engine and connecting it back to the spark plug cable. Place the electrode part of the plug on a grounded part of your machine, such as the cylinder. Then try starting your ATV again.

If your spark plug is good, you will see some spark jumping from the plug to the grounded part. You need to replace the spark plug if you don’t notice sparks coming out.

Carburetor

Of course, your gas tank is full of fuel, but the engine might still not get enough to consume. There are several reasons for the engine not getting enough fuel, and you can fix them too.

Start by checking the fuel pump or carburetor. Dirt accumulation in the carburetor can block the fuel supply, and you want to clean it. You also want to check the gas line and clean it if it blocks the fuel supply.

Air Filter

You know your machine needs fuel and spark to start, but not everyone knows the importance of airflow in starting an engine. Combustion must occur for your quad to start, which requires enough air to mix with the fuel.

Air flows through the air filter but can obstruct airflow when dirty. If it has been a long time since you changed your air filter, try and replace it, as it makes sense to replace it after a while, say a year or two.

Another reason your engine might not get enough air is an object blocking the air box intake.

Compression

When your ATV engine turns over but won’t start, another place to check is the compression department of the engine. Your engine needs enough compression to pull fuel into the cylinder. The compression department is sealed up, so there is no leakage.

Once your vehicle has a blown piston ring or the head gasket leaks, the engine gets low compression and might not start. This might require the service of a professional ATV mechanic to fix, though.