Outboard does not start - what can I do?
If your motor won't start, there's no need to panic. There are usually a few different reasons as to why this is the case and most problems can be dealt with quickly and easily.
1 Spark plugs
One reason why your engine won't start could be because of dirty, wet or faulty spark plugs. Give them a clean and try to start your outboard again. If it still won't start, replace the plugs.
Our tip: Always carry spare spark plugs on board.
If you’re having problems getting your outboard going, it may be because your fuel tank is empty or the fuel in it is old. Either way, in both cases you'll need to put new fuel in your outboard. Make sure you drain off old fuel completely.
Our Tip: Use a petrol stabiliser to protect your outboard fuel from ageing.
3 Kill switch disconnected
The kill switch on your outboard is for your protection and must be connected when using your motor. If the emergency shut-off switch is not activated, your engine will not start. Make sure it's connected if your motor won't start.
4 Fuel valve
Boat motor won't turn over? It could be because a fuel valve is closed. Try opening the fuel valve so that your motor is supplied with fuel and start the engine again.
5 Air vent not open
Outboard motor won't start and you don't know why? Check the air vent on your outboard tank. Make sure it is open, otherwise your motor won't start.
6 Incorrect storage
A further reason for your outboard not starting could be that it was not stored correctly. If done badly, engine oil can leak and flow into the combustion chamber and carburettor. In these cases, your outboard will not start. Clean your carburettor, top up your engine oil and store & transport your outboard properly next time. You can find out how to transport outboards correctly in our guide to starting your outboard, fuelling and transporting.
Outboard motor starts and then stops again - what can I do?
Why does my outboard motor start and then immediately stop again? There are various ways you can stop this from happening and preventative measures you can take.
Does your outboard motor start and then stop again? Check the carburettor. One reason could be that your carburettor has become clogged or the adjustments are too lean. Remove the carburettor and clean it with ultrasonic cleaner or brake cleaner.
Our Tip: Use petrol stabiliser and protect your engine!
A dirty or clogged filter (if fitted) could be why your outboard motor keeps starting and stopping. Clean your filter and try starting your outboard again. If the engine stops, you may need to replace the filter.
3 Air vent not open
Your outboard might cut out straight away after starting if the tank air vent is closed. Open the vent and try starting it again.
Even only slight overheating of your outboard can lead to long-term damage! An outboard can overheat for various reasons, including a worn-out seawater pump, an old and cracked, defective impeller, or no blades on the impeller. The outboard can also be damaged if it is not started in the water, because the water pump impeller could be damaged and the engine can overheat.
There are two ways you can tell if your engine is overheating:
- If the water coming out is hot, or no water coming out. A supply of water is necessary to keep the engine cool.
- Check the temperature gauge, if there is one.
Overheating can result in a defective outboard motor.
Tip: In general, regular maintenance and care of your outboard motor can prevent any potential problems from occurring.
Fishing line caught in the
Fishing lines in the propeller are a relatively common problem with outboards. They can be hard to spot and sometimes hitting them is unavoidable. Fishing lines can quickly get caught on the propeller shaft of outboards, on the propeller itself or wrap around the entire shaft.
Problem: The fishing line can get into the shaft seal and damage it, causing either water to enter the gearbox and damage it or oil to run into the water.
How to fix the problem of a fishing line caught on the outboard propeller:
- Switch off your outboard motor (if it does not stop on its own). Normally, the engine will switch off by itself if it is blocked.
- Paddle to land if possible.
- Remove the prop screw.
- Use a knife or other tool to remove the line and all pieces from the drive (shaft, propeller & shaft).
- Inspect the propeller, drive & shaft for possible damage.
- You may need to check for water in the gear oil. To do this, take the engine out of the water and loosen the lower screw. Since water is heavier than oil, if water has penetrated the gear oil, water will come out first.
- If there is severe damage or water in the gearbox, check the shaft seal:
- Perform a pressure test on the gear box.
- If pressure is maintained, the oil seal is intact.
- Replace the screw and enjoy your boat!
Tip: On longer trips we recommend you take a spare propeller with you.
Written by our SVB (technical) experts
Our team of SVB technical experts is there to give our customers professional advice on all matters relating to technology on board. Their expertise is the result of regular training and many years of experience.