What To Do If Your Boat Won't Start While You're On The Water

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Nothing ruins a day on the water faster than turning the key and realizing your boat won't start. This can not only be an inconvenience, it can quickly turn an enjoyable day into a dangerous situation, especially if it is getting dark or bad weather is moving in. While not every boat motor malady can be fixed while on the water, quite often there is a simple solution to getting your boat back underway. More often than not, it is a matter of knowing what to look for and how to resolve these issues.

Although boating mishaps are among the most common ways people die while fishing, if you find yourself in this predicament, don't panic. Rather, remain calm, make sure all your emergency boating equipment, such as your fire extinguisher, is readily accessible. Don your life jacket (if you aren't already wearing it), and begin troubleshooting to attempt to find the problem. It is also a good idea to alert someone to your predicament by signaling nearby boaters and/or calling a friend or family member on shore. If you have a tow service membership, such as TowBoatU.S., use it — especially if weather conditions are deteriorating.

Once you are ready to begin troubleshooting, start with simple solutions. Make sure your gear shift is in neutral, as engines are designed not to crank if they are in gear. Also glance at your emergency kill switch, which is designed to cut power to the engine in an overboard emergency situation. However, at times, this clip may be inadvertently dislodged. Ensure it is firmly positioned, then try starting the engine again. Next, check your fuel level. If possible, do so by looking at or in the tank itself, as gauges can malfunction and give false readings.

If the immediate actions didn't resolve the issue, there are still several simple checks you can perform to get your boat going again. Very, very often, a non-starting boat motor isn't due to any motor malfunctions, but rather the boat's electrical system. Given that boats are in wet and humid conditions, electrical connectors, which are made of metal, often rust and/or corrode in addition to getting dirty and grimy. This is even more pronounced in saltwater environments. Additionally, the vibration and bouncing that boats experience when underway can cause connections to loosen over time.

With that in mind, checking your battery connections will quite often reveal the problem. Make sure connectors are not just tight, but also clean and free of rust and corrosion so that there is good metal-to-metal contact. Remove your battery terminal connections and clean them with a wire brush, then replace them, and tighten them securely. Performing this task is much easier if you keep a basic tool kit, like the GreatNeck MS125 Marine Tool Set, that has essential tools like an adjustable wrench, pliers, screwdrivers, and wire brush aboard your boat.

If cleaning the battery terminals did not solve the issue, take note of what happened when you turned the key. An engine slowly turning over is a sign your battery may be low. Should nothing at all happen, the battery may be dead or another connection may be fouled. So, check the remainder of your electrical connections, as well as any fuses related to the motor and ignition system. If you have another batter on board, try using it to start the engine. On the other hand, if the engine turned over normally but didn't start, you may have another issue to deal with. 

If the engine is turning over normally but not starting, you are likely not getting fuel or fire. So, turn your attention to the fuel system. Check and make sure none of the fuel lines are kinked and inspect all fuel and air filters. Make sure air intakes and exhaust ports are not being obstructed or blocked. Fuel filters that show signs of debris or water should be drained and/or replaced. This requires placing a bucket or other container under the filter when removing to prevent fuel leaking or spilling. Be sure to keep the drained fuel secure until you are back at the dock and able to dispose of it properly. 

Next, be sure your engine is primed by squeezing the primer bulb repeatedly until it is firm. Boats with an electric primer will prime a few seconds after the key is turned to the "on" position. If the engine still doesn't start after priming, make sure the fuel is getting to the engine by removing the line between the primer and engine and checking for flow. Take care to catch any fuel that comes out of the line in a bucket or container.  You should also check the choke linkage, making sure it moves freely and is not damaged or bent. 

Should none of that solve the issue, fouled spark plugs may be your problem. In this case, it will be necessary to remove the spark plugs, clean them, and replace them. This will require a spark plug wrench — another good item to keep on board — and a wire brush. For boats with outboard motors, it is often helpful to tilt the engine up as far as possible before attempting to remove the plugs, as you will have much easier access to them.