Boat Motor Won’t Start: Top Tips to Find out Why and Fix the Problem

30 October 2020 On The Water

boat motor won't start

What do you do when the boat motor won’t start?

Boat motors have a lot of parts but there are a few simple things to check when trouble first arises.  Most of the time you can solve a basic issue yourself and avoid the inconvenience and expenses of taking the motor to a repair shop.

Problem: Boat Motor Won’t Do Anything

1. Check the battery connections.

2. Check the battery charge.

3. Check the spark plug connections.

4. Remove and check the spark plugs. Clean the spark plug points with a piece of sandpaper.

5. Re-install the plugs and try to start the motor.

6. Replace the plugs with new ones.

Problem: Boat Motor Will Spark but Not Start

1. Check the fuel line connection.  It must be connected correctly to both the tank and motor.

2. Check the fuel tank. The vent must be open to allow air to enter the tank (external tanks).

3. Prime the fuel line. This brings fuel to the motor.

4. Pull the choke. This closes the plate that allows the air into the carburetor.  A higher fuel-to-air mixture improves starting conditions.

Problem: Boat Motor Will Start but Quits or Chugs Badly

1. Check the fuel tank for adequate fuel.

2. Check the choke. The choke lever must be pushed back in once the motor starts to allow air to flow into the carburetor.

3. Check for water in the fuel tank. Condensation will form in the tank and when mixed with the fuel will inhibit the operation of the motor.

How To Check for Water in the Fuel Tank?

1. Siphon the fuel into a clear plastic jug.

2. Let the old fuel sit for 20 minutes.  The water will settle to the bottom.

3. Siphon the clean fuel back out of the plastic jug, leaving only the settled water.

4. Place the water-free fuel back into the tank, or use fresh fuel.

Need more boat motor and boating tips?
Got to the Boat Motor Tilting Advice page.
Go to the Boat Trailer Maintenance page.
Go to the Spring and Fall Boat Maintenance page.