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Getting to know your Outboard Motor

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Getting to know your Outboard Motor

Table of Contents

Outboard Motor Parts

Discover the main components of your outboard motor, the different types of outboards available and what type of replacement boat parts are recommended by experienced boaters.

Parts of an Outboard Motor

There are three major sections of an outboard motor which are the powerhead, the midsection and the lower unit. The midsection includes the exhaust housing, the lower unit includes the gearbox and has the anti-ventilation plate, water intake propeller and skeg.

Powerhead: The powerhead includes the engine which is usually not put in the water. To start an outboard motor, a person must use a pull cord which provides the spark that gets the cylinders firing on the downward stroke. Most engines are cooled by water. Parts included in the powerhead include the fuel tank, a speed control lever, the carburetor, and the reed valves.

Midsection: The midsection includes the mounting bracket and the exhaust housing. The bracket is used to attach the motor to the boat and the exhaust housing removes the used elements from the engine.

Lower Unit: The lower unit includes the propeller that provides the boats propulsion. The propeller can be tilted so that it does not hit the bottom in more shallow waters. The skeg is the sternward extension of the keel that has a rudder mount under the center line. The propeller is usually made of aluminum but there are also stainless steel propellers that are stronger then aluminum.  
The lower unit is one of the most commonly damaged part of a boat motor.  Often times trees and rocks lurk under the water where they can not be seen and once the motor hits the obstruction, damage to the lower unit results. There are several affordably priced options to replacing your lower unit.  Watch this video for more information on replacing your lower unit.

Next, find a shop with options and one that is willing to work with your insurance. Most importantly, don’t always choose the lowest priced option.  Look for knowledgable and helpful staff who will give you honest answers, not just the answer you want to hear to get the sale.

Undertaking your own engine repairs is a great way to feel accomplished and become a proud boat owner. Many even see it as a relaxing past time. Always ensure you understand all the concepts, parts and procedures regarding boat repairs before beginning your project.

Types of Boat Repair Parts

Quick Silver water pump impeller by Mercury Marine

Boat repair parts should always be purchased from reputable marine retailers that specialize in outboard motors and repair parts. Owning an outboard motor comes with immense responsibly for caring and ensuring it functions at its optimal level. Through wear and tear, it is inevitable that a time will come where there will be a need for occasional parts. Understanding what type of parts are needed as well as knowing which the best outboard motor parts to purchase, is imperative in successfully repairing or maintaining your boat. There are steps in understanding what you need:

  1. Know your outboard manufacturer name. If you own a Mercury Outboard, you need Mercury outboard parts or an Evinrude needs Evinrude parts and so on. Even though this step seems quite obvious, you will surprised to learn that many end up buying wrong parts or even aftermarket parts as it’s a cheaper alternative. The saying “pay now or pay later” holds true in this regard, as you don’t want to regret not getting the correct OEM parts. Buying the wrong parts is clearly a waste of time.
  2. Next, find your model number and serial number. You need your model number for Evinrude, Johnson and OMC products. Mercury Marine products require your serial number for parts look up.
  3. You also need to know what component you need to fix i.e. lower unit, fuel pump etc.
  4. Finally, you will need to locate your part. It’s  useful to use a boat motor parts diagram to find the specific parts of a boat motor that need repairs. Always remember to buy the nuts, bolts and gaskets as well.   Try where you can find great boat engine diagrams that link directly into a boat parts shopping cart.

Types of Outboard Motors

Verado 350hp 15hpPK FS Lund 219ProV FW GrandRapids W2F 763A2590 scaled

Large Motors: Large outboard motors are usually for boats 37 feet or longer and are motors that have powerful V6 and V8 cylinder blocks that are rated up to 557 horsepower. The large outboard motors are usually bolted or bracket bolted to the transom and have controls that are linked to the helm. There are also large outboard motors that have two to four cylinders that can generate 15 to 135 horsepower that are suitable for hulls up to 17 feet.

Portable Motors: Portable outboard motors are relatively small and go up to about 15 horsepower. Camps are used to affix and remove the motor from the boat. Portable outboard motors are usually started by a manual pull cord hand have both the throttle and gearshift controls on the side of the motor. A tiller is used for steering and the motors are usually used to power small craft, provide auxiliary power for sailboats, and provide small craft the ability to troll along with other larger craft.

Electric-Powered Motors: These are also known as trolling motors, and are usually only used on small craft or when gasoline-powered motors are not allowed. They are much quieter and cause zero emissions.

Pump-Jet: This type of motor is a marine system that creates a jet of water for propulsion. The pump-jet engine has an intake that allows water to pass below the vessel into the engines. Water enters the pump through an inlet.

So there you have it. We covered the main components of an outboard motor, different types of outboard motors and ways to find and purchase outboard motor parts. If you need help in finding the correct boat parts for your older motor, try USBoatworks. We stock over 2 million boat parts that can ship to you today. You will find a helpful staff the will assist in locating the parts you need and best of all, we only sell OEM parts so you will get the best quality engine parts that will last.