Table of Contents
How do 4 stroke outboard motors work?
A four-stroke engine works by running one compression stroke followed by an exhaust stroke. Each stroke is followed quickly by a return stroke. Most four-stroke outboard motors on the market today feature high-tech computer management systems to keep the motor running smoothly, which grants them great performance.
Can you run an outboard motor without water?
An outboard motor should never be operated without a source of water entering the inlet screens to supply the water pump. Without a source of water for lubrication, the water pump will be the first to be damaged, followed shortly thereafter by the engine from a lack of cooling.
How does an outboard motor start?
Used outboard motors require just the right touch. Outboards start like a car; just tilt them down and turn the key.
How does a small outboard motor work?
The crankshaft turns the main driveshaft running down the long spine of the motor. A small gearbox at the bottom of the driveshaft converts vertical spinning motion into horizontal spinning motion. The propeller powered by horizontally spinning gears powers the boat through the water.
How do outboard motors get air?
Marine engines typically will not have a true air filter. There’s an air box in front of outboard engine carburetors to quiet the sound of air rushing into the engine. Inboard motors use a flame arrestor on their carburetors to eliminate the possibility of fire and bilge explosion.
Is a 4 stroke outboard more powerful than a 2 stroke?
This is why 2 strokes are used in handheld, portable things like chainsaws, lawn mowers and on smaller boats. The 4 stroke also has a lot more extra parts & complexity that adds to the weight of it. Obviously a 2 stroke 60HP has the same power as a 4 stroke 60HP but it is how that power is delivered that changes.
Should I leave my outboard motor up or down?
You want to leave the engine in the totally trimmed down position. This will allow all of the water to leak out of the engine, midsection, and lower unit. Making sure that there is not any water in the Lower Unit that could rust gears or freeze and destroy the gear case by flushing the engine with fresh water.
How often should you change the water pump on an outboard motor?
How Often Should You Change the Water Pump On Mercury Outboard? In most cases, you won’t need to replace the water pump unless the housing is damaged. Instead, replacing the water pump impeller every three years or sooner should avoid most water-pump-related issues and keep your outboard running in excellent condition.
What are muffs for a boat?
Flush muffs are the most common way to flush an outboard; they’re available at most marine stores and online resellers. They’re inexpensive, and easy to use. Connect to a garden hose, fit the muffs over the engine’s water intakes on the sides of the gear case, turn the water on, start the engine, and let it run.
Do outboard motors have keys?
Outboard motors are simple. Depending on the type of motor you have, you might have to pull start it, or you may need a key. Once the motor is going, you can use it to drive your boat until you are ready to stop and coast.
How do you manually start an outboard motor?
Manually starting an electric-start outboard Remove the cowling. Tie a knot in the end of a 6 mm (1/4″) rope and wedge the knot into the notch on top of the flywheel. Wrap the rope around the flywheel in the correct direction (clockwise, for this 1994 Johnson J30). Set the choke and throttle. Pull really hard.
What is the fin on the bottom of a outboard motor called?
What is the purpose of a skeg? The skeg of your outboard or stern drive motor serves two highly important functions. The skeg acts as a precise rudder, allowing the motor to turn your boat accurately and safely. Second, The skeg allows essential protection of your propeller from debris in the water and running aground.
How does an outboard motor shift gears?
The pinion gear is permanently engaged with the forward gear and the reverse gear, so when the driveshaft is rotating, the pinion gear is rotating, and the forward and reverse gears are rotating. If you hear grinding as you shift the outboard into gear, it’s usually a worn dog clutch.
Why should a boat gas tank never be full?
It’s important to never fill the tank of your boat beyond 90% full. This leaves room for gas to expand and avoids the potential for overflow. Ensure that all air vents and valves to the gas tank are open.
Is it OK to start a boat out of water?
Starting a boat without water is not recommended. Most outboard and inboard engines use impellers (rubber pumps) to run water to the boat’s cooling system. Without water to cool off and lubricate, the impeller will heat up super fast and possibly damage.
Is it OK to leave boat uncovered in rain?
Not only will the rain damage a boat’s interior, but leaving it without a cover exposes it to the sun’s harmful rays. A boat left without a cover while not in use, will lose value very rapidly. Even when you have a cover that’s in poor condition, it’s better than no cover at all, until you can get a new cover.
Where does the exhaust come out on an outboard?
Most all of the exhaust of an outboard is expelled through the bottom fin of the propeller. This is why there are bubbles coming up from the propellers when the boat is started. This exhaust is also mixed with some water from the cooling system. It cycles through the engine and then is pushed up with the exhaust.
How does an outboard motor fuel pump work?
Fuel pumps on outboard motors work a little bit differently than they do on automobile engines. The outboard fuel pump has a sensitive diaphragm that receives a suction signal from a piston cylinder so the pump can deliver fuel.
Why do boats run water through exhaust?
Use raw water from its surroundings to keep the engine cool, which flows in through the seacock, and is expelled through the exhaust. Are often quieter than dry exhaust engines, because the water absorbs the noise and heat, which is why many boaters prefer them.
Do outboard motors pollute water?
Two stroke motors can emit 25-30% of their unburned gas and oil mixture into the water. In contrast, four-stroke motors emit 97% less air and water pollution than old two-stroke motors. This pollution can affect the pH and dissolved oxygen in the lake, which can influence the type and abundance of fish and wildlife.
