Complete Outboard Boat Lower Units
An outboard lower unit is necessary for piloting any marine craft. This is the portion of the engine that sits below the surface of the water giving any motorized boat or outboard its momentum. Having these systems in good working condition is key to enjoying your time off land.How do you change the oil in outboard lower units?
Before replacing the oil, you will first need to drain old fluid completely. Remove the top screw first, followed by the bottom screw. Allow all of the fluid to drain out. Make an inspection of the fluid to ensure that it isnt milky in color and that there are no metal shards present. If you do notice these symptoms, you will need to make other repairs to your marine craft before proceeding. If these problems are not present in you can continue.
- Connect the pump to your bottom drain hole.
- Replace with oil until you see the fluid coming out of the top hole.
- Replace the top screw and quickly remove the pump.
- Reinsert and tighten the lower screw.
- These parts are located in the lower pump base. You will first need to drain any oil. Remove the assembly for the water pump and the impeller.
- Using two straight screwdrivers, pry upwards on each side of the pump assembly. You will need to install a new gasket and two O-rings when reassembling.
- Pry out the two seals and use an inverted socket which is a size larger than the seal so there is no damage to the seal lips. Using grease, lube the seal well. Install your new O-rings and lube well when installation is complete.
- Install your new gasket and reposition the assembly back together. Make sure that you dont overtighten.
- Reinstall the water pump assembly back into position and secure tightly. Refill the oil as recommended
The driveshaft is an important component of any marine craft. Whether repairing or inspecting this part in your boat or outboard, it is necessary to get a clear view when working on it. This makes it necessary to remove the driveshaft on occasion. Follow the steps below to remove the driveshaft to repair or replace these parts.
- Remove the bolts that connect the exhaust assembly and lower unit using a socket wrench. Slide your lower assembly straight down and off. Set it upright in a bench vise to ensure it is not damaged.
- There are four bolts that hold your water pump and the water pump housing together that must be removed. Slide the lower unit and impeller up and off of the driveshaft. Slide the impeller plate off from the lower unit and driveshaft.
- Remove the retaining bolts from the bearing carrier. Place two small pry bars, one on each side, under the lip of your bearing carrier. Using a gentle force, pry the housing and your propeller shaft an assembly setup.
- Use a small pry bar to loosen the fit that is found between the housing and your lower unit. In an upward motion, remove the bearing assembly, driveshaft, and retaining rings.