When it comes to choosing one of the best outboard motors, Yamaha scores very high for that.
This is due to the series of reliable outboard motors that they have produced.
This includes the Yamaha 115.
But that does not mean that it cannot or does not develop problems.
Yamaha 115 outboard bogs down at full throttle when some of the components in it is faulty.
Some of the reasons why Yamaha 115 loses power at full throttle includes overloading, use of contaminated fuel, poor cylinder compression, lack of timely maintenance, faulty propeller as well as faulty ignition system.
These flaws affect the performance of Yamaha 115 negatively.
Due to this, the performance of the Yamaha 115 outboard motor will reduce.
Why Yamaha 115 Outboard Loses Power At Full Throttle And How To Fix It
1)Use Of Contaminated Fuel
Before an outboard can function, combustion has to take place in the combustion chamber.
With this, the outboard motor will be able to generate power through the power stroke phase.
But for this to be possible, fuel has to be ignited in the combustion chamber.
The quality of performance that is produced after fuel ignition in the combustion chamber is determined by the quality of fuel used.
If a premium quality of fuel is used, the Yamaha 115 outboard motor will be able to produce power effortlessly.
But if a bad quality of fuel is used to run the outboard motor, the performance will be poor.
One of the things that can contaminate a fuel is when it contains water in it.
Another way fuel can be contaminated is when it contains dissolved particles in it.
This reduces the efficiency of the outboard motor especially when it is at full throttle.
Solution
a)Use Good Fuel
When making use of your Yamaha 115 outboard motor, you have to make sure that you use a good fuel.
This will help the outboard motor to effectively ignite the fuel mixture in the combustion chamber.
With this, power will be generated to help the outboard motor perform well.
2) Faulty Spark Plug
Before power is generated in an outboard motor, combustion has to take place.
It is at the power stroke that power is generated by the outboard motor.
But for the power stroke phase to be efficient, the fuel mixture in the combustion chamber has to be ignited.
This ignition of the fuel mixture in the combustion chamber is made possible with the help of the spark plug.
But if the spark plug is not performing well, Yamaha 115 will lose power at full throttle.
To avoid this, a good spark plug has to be used always in running an outboard motor.
Some of the things that makes a spark plug to perform poorly is when it is fouled or damaged due to extensive usage.
Solution
a)Use Good Spark Plug
While making use of your outboard motor, you have to make sure that the components are working well.
This is what is going to guarantee a smooth performance from the outboard motor.
One of these components is the spark plug.
If you discover that the spark plug is bad, you have to replace it with a good one.
This will help your Yamaha 115 outboard motor to reach full throttle without losing power.
3) Poor Cylinder Compression
The compression in an outboard motor cylinder is very important.
This is what builds the pressure needed to give the piston a good push.
With this, the piston is able to deliver power that moves the boat well.
But if the cylinder has a poor compression, then the outboard motor will not perform well.
This is due to the power loss that will occur due to faulty piston, faulty engine block or any other reason that causes low compression in the cylinder.
Low compression in a cylinder will reduce the performance of the Yamaha outboard motor.
This is one of the major reasons why Yamaha 115 outboard bogs down at full throttle.
Solution
a)Rebuild Engine
When you discover that your outboard motor is not performing as it used to perform when it was new, you have to troubleshoot for faults.
One of the places to troubleshoot is the engine of the outboard motor.
What you do here is to perform a physical inspection and check for things like crack in the engine block.
You should also make sure that you perform a compression test across all the cylinders of the Yamaha outboard motor.
If you notice any cylinder that has a low compression, then you have to fix it.
This will help your Yamaha outboard motor to perform well again especially when you try to reach full acceleration.
4) Bad Ignition Coil
For power to be generated in an outboard motor, the ignition coil has an important part to play.
Before power is generated in an outboard motor through the power stroke, combustion has to take place in the combustion chamber.
But for the combustion to take place in the combustion chamber, the fuel mixture has to be ignited.
After the ignition of the fuel, the pressure that is developed is what forces the piston down to produce power that spins the propeller.
But for this ignition to take place, the spark plug has to burn the fuel in the combustion chamber.
For the spark plug to function, it depends solely on the charge it receives from the ignition coil.
This is because the ignition coil acts as a transformer by supercharging the electric charge before releasing it to the spark plug.
If the ignition coil is not performing well, effective power will not be generated from the outboard motor.
Solution
a)Replace Faulty Ignition Coil
When you discover that the ignition coil that is in your Yamaha 115 is not performing well, you have to change it.
By replacing it with a new one, you have to make sure that the capacity of the new one matches with the Yamaha 115 outboard motor.
This will help the outboard motor to produce better power and avoid loss of power when accelerating.
5) Faulty Propeller
A propeller needs power from an outboard motor engine to function
At some point, the propeller in an outboard motor can be the sole reason why an outboard is not performing well especially when accelerating.
This is usually due to a wrong selection of the propeller.
Apart from a wrong selection of propeller for an outboard motor, things like seaweed can make a propeller to affect the performance of an outboard motor negatively.
This happens when the seaweed entangles the propeller and prevents it from moving freely.
Solution
a)Use a Good Propeller
In making use of your outboard motor, you have to make sure that you use a good propeller.
This will help make sure that the performance that you get from your outboard motor is great.
b) Free Propeller From Obstacles
As you keep making use of your outboard motor, the propeller might attract things like seaweed.
This will affect the performance of the propeller when it is spinning.
As a result of this, the performance of the outboard motor will suffer too.
That is why timely maintenance has to be done on the outboard motor and boat to correct issues like this.
6) Overloading
When Yamaha outboard motor loses power at full throttle, one of the key areas that has to be checked is the load imposed on the boat.
All outboard motors have a certain range of load they can easily move.
If you exceed this load range, the outboard motor will struggle to move the boat.
This will result in poor performance from the outboard motor.
Solution
a)Avoid Overloading Boat
When you are making use of your yamaha 115 outboard motor, you have to make sure that you know of the maximum load that can be imposed on the boat that the outboard motor powers.
This will help avoid imposing excess load on the boat.
7) Overheating
As much as you can, make sure that you stay away from negative practices that leads to yamaha 115 outboard overheating.
One of the common reasons why an outboard like the Yamaha 115 overheats is when the cooling system is faulty.
When the cooling system of an outboard motor is not performing well, the temperature of the outboard motor will not be well regulated.
As a result of this, the Yamaha outboard motor will overheat.
When the outboard motor overheats, power loss in the outboard motor will occur.
This will cause the Yamaha 115 outboard motor to lose power when throttling.
Solution
a)Fix Faulty Cooling System
When you discover that your outboard motor is overheating, one of the common cause of this is a faulty cooling system.
This does not mean that other things cannot cause an outboard motor to overheat.
A bad oil or low oil level can also lead to overheating in an outboard motor when the oil cannot properly regulate the temperature of the outboard motor during combustion.
To solve this, you have to perform a troubleshooting to determine the root cause of the overheating.
When you discover the cause of the overheating, you have to fix it.
This will help your Yamaha outboard motor to perform well and not lose power when accelerating.
8) Lack Of Timely Maintenance
For a continuous flawless performance to be possible when making use of your outboard motor, timely maintenance is a great necessity.
When you perform timely maintenance on your Yamaha 115 outboard motor, you will be able to discover some parts that are not functioning well that affects the performance of the outboard motor.
With that, you can easily repair or replace it with a good one.
This will help your outboard motor in maintaining a flawless performance.
Solution
a)Perform Timely Maintenance
With every outboard manufacturer, a certain period is specified for maintenance to be carried out while making use of the outboard motor.
This helps in checking and repairing failed parts of the outboard motor.
With this, the performance of the outboard motor will be improved.
Cases in which Yamaha 115 outboard bogs down at full throttle will rarely occur while making use of the outboard motor when you perform timely maintenance.
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