How to Adjust Slow Speed on a 6 HP Johnson Outboard

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Adjusting the slow speed on a 6 HP Johnson outboard motor regularly will keep the engine running efficiently and provide better fuel economy. The slow-speed idle adjustment screw, also referred to as the low-speed needle, is located near the front of the outboard motor carburetor. The slow-speed idle adjustment screw can be adjusted in just a few minutes with a screwdriver, saving you time and money.

Items you will need

  • Screwdriver

Step 1

Turn the slow-speed idle adjustment screw clockwise with a screwdriver until the screw is seated without over-tightening the screw.

Step 2

Adjust the slow-speed screw by turning it counterclockwise 1 1/2 turns with a screwdriver to find the starting point for further adjustment.

Step 3

Start the outboard motor and let it warm up for about five minutes. Set the throttle at a slow trolling speed.

Step 4

Adjust the slow-speed idle by turning the screw clockwise 1/4 turn at a time until the motor begins to stall; then turn it back counterclockwise 1/4 turn to find the proper setting on the 6 HP motor.