4 Steps To Take If Your Outboard Quits

By Lenny Rudow
Published: Summer 2013

You're putt-putting along pretty as you please, when suddenly your outboard dies. Major bummer!

Photo of a lanyard

1. First, make sure you're safe — power losses can be dangerous if there are heavy seas or bad weather. If possible drop an anchor or deploy a sea anchor to keep your bow into the waves, and if a storm is brewing, batten down the hatches and lower any antennae, fishing rods, or outriggers that may attract lightning strikes.

2. FUEL problems are often the reason for a sudden shutdown. Check the filters and/or fuel/water separators, and make sure they're not clogged. If you've recently started using gas with ethanol, it can act as a solvent to loosen gunk in the tank that can quickly clog the filter. (You have a spare, right?)

Next, check your fuel supply, the primer ball, vents, and fuel lines — in that order — to make sure you have a flow going. If there's too much pressure, suspect a faulty fuel-line connection; if there's negative pressure, you have a venting problem; and if there's a complete lack of pressure, you probably have an air leak in the line. If the system looks good (and especially if the engine shuts down suddenly, completely, and without warning), chances are you have water in the fuel. If that's the case, call TowBoatUS because you have a more serious problem.

3. If the fuel system checks out, then ELECTRICAL problems should be your next suspicion. Obviously, if your battery is completely dead, there's not a whole lot you can do about it. But there are some other common electrical problems that can leave you high and dry, yet can also be easily addressed. One is a faulty safety switch, which “thinks” the engine is in gear even when it's in neutral. So, give the throttle a jiggle, then try holding the key on while shifting the throttle through neutral.

If the engine turns but won't catch, your engine cutoff switch may have a short. This happens often when the switch is mounted horizontally on an exposed helm, where water can pool and get into the switch. Try circumventing it, and see if this gets you back in action. Simply look behind the helm and find a black wire with a yellow stripe, which leads to the switch. Disconnect it, and then try the key again.

4. If the cut-off switch checks out OK, then it could be that a TEMPERATURE issue shut you down. Usually, that's the result of a lack of cooling water. If the outboard isn't discharging water at the usual rate, you could have a serious problem that requires attention on land. Before you give up hope, however, check the rawwater intakes on the lower unit. Sometimes a plastic bag, a piece of paper, or some seaweed gets sucked in and stops the water flow. Remove the discourteous clog, and you'll be fine.

Another relatively common problem comes in the form of a stuck thermostat. Sometimes you can pop it free and clean it up, and then continue on your merry way. If none of these quick fixes work, then you may have to wait for that tow.


Lenny Rudow is BoatUS Magazine's electronics editor.


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On-the-Water Troubleshooting

Before you make the call, check the following:

  • Is the safety lanyard attached to the engine key? If it isn't, the engine isn't going to start.
  • Is the throttle shift control in neutral? If it isn't, the engine won't start.
  • Is a vent closed on a portable gas tank?
  • Check if the fuel line running to the outboard kinked as a result of heavy wakes or rough seas.
  • If engine runs but suddenly shuts down when put into gear, that's a symptom of a line wrapped around the prop.
  • If the engine suddenly stops, take a look at water intake valves on the lower unit for any seaweed or plastic bags that are blocking the intake. Many engines will shut down automatically as a result of an overheat caution system that's designed to protect it.
  • Inspect the battery post for evidence of a loose connection. Ensure the nut holding the cables on the battery posts is tight. Also look at the connection itself for dirt. Clean the posts with sandpaper (some have used a Scotch-Brite pot scourer with success), wipe clean, apply an anticorrosive lubricant (Vaseline has been known to work in a pinch), and then retighten the battery cables.


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