If you have an old Johnson outboard motor you will eventually need to replace the water pump or even the entire lower drive assembly. An outboard is made up of three primary components: a powerhead that houses the engine; an intermediary shaft that separates the powerhead from the lower unit; and the lower unit, the part of the motor that’s submerged in the water with the propeller. Typically four bolts hold the lower unit to the intermediary shaft.
Open the outboard motor powerhead cover and locate the spark plugs on the rear of the engine. Disconnect the wires from the plugs by pulling them straight off to prevent accidental starting of the motor.
Place the outboard on a motor stand out of the water to allow access and a stable platform with which to work. Locate the four bolts holding on the lower unit, …