How to Install a Water Pump on a 150 Johnson Outboard Motor
- 1). Remove the nuts from underneath the top lip of the 150 Johnson outboard gearbox with a socket wrench, and slide the gearbox away from the engine housing. Place the gearbox in a vise, and take the bolts off of the top of the water pump housing with a socket wrench.
- 2). Slide the water pump housing over the motor shaft, and remove the pump housing from the gearbox. Take the water valve off the top of the pump housing, and remove the metal plate and rubber gasket from the top of the gearbox.
- 3). Clean the top of the gearbox with a clean cloth to remove any oil deposits or remaining debris. Apply a thin layer of marine grease to the top of the gearbox where the water pump housing sits as well as along the base of the motor shaft.
- 4). Place the water valve from the old pump housing onto the new pump housing from the water pump rebuilding kit. Apply a thin layer of marine grease to the inside edge of the pump housing, and insert the new impeller from the rebuilding kit upside down in the new pump housing.
- 5). Put the new O-ring on the bottom of the water pump housing, and place the new rubber gasket on the top of the gearbox. Place the metal plate over the rubber gasket on the gearbox with the rounded edge facing upward.
- 6). Slide the new water pump housing assembly over the motor shaft, and secure the pump housing assembly to the top of the gearbox with bolts. Remove the gearbox from the vise, and slide the gearbox onto the engine housing.
- 7). Fasten the gearbox to the 150 Johnson outboard engine housing with the nuts.
Source...