In this post, I’ll walk you through how to fix a Honda TRX 400EX that won’t start. This is a fairly common problem, much like the time I ran into it on my own Honda when it turned over but didn’t start. But if you have any other questions or concerns, please feel free to contact me.
If you have time to watch a video to fix your Honda TRX 400EX, then cool. i am embedding a great one for you.
Before we go any further, I need to ask you one question: does your starting motor turn over when you turn the key? Your answer will determine how the method for selecting the solution is carried out in a different way. Both of these situations will be addressed in this blog post. So, buckle up, mate!
Starter Motor Isn’t Working
First things first, let’s make sure we have all the essentials covered: Have you turned off your ignition switch, or is it on? Check to see that the key for the engine stop is in the correct position. Is the Transmission set to a neutral gear? Continue reading if everything is in the starting position.
Check Battery
After making sure the key is in the on position, we need to make sure the battery has a voltage of between 12.5 and 13 volts. If the voltage has dropped, then the issue is with your battery. You need to charge it manually. To avoid having to charge the battery by hand if the voltage drops below this level, check it often. A dead battery is no longer safe to use and should be replaced immediately.
Have A Look At The Fuse
It is fairly unusual for the main fuse of the 400ex to blow due to overuse. In this instance, a new fuse will resolve the issue. A fuse box is located to the left of the battery. You have the option of replacing the main fuse or using the spare fuse that Honda includes in the package (15A Fuse).
Starter Solenoid Could Be The Issue
If the primary fuse has not blown and the battery is still producing power, it is possible that the starting solenoid is the source of the problem. The solenoid is responsible for regulating the flow of power from the battery to the starting motor.
First things first, get a voltmeter and check to see whether the battery is supplying the solenoid with energy. Investigate the connections between the battery and the solenoid in the event that there is no electricity.
If the starting solenoid is receiving power, there shouldn’t be a click that can be heard coming from it. Lastly, check to see whether power is being sent via the solenoid. If the battery, fuse, and solenoid are all in working order, the problem is most likely with the starter. As a result, the starting motor will need to be replaced.
If you haven’t found a solution to fix a Honda TRX 400ex that won’t start, then don’t worry the next stage of the guide might help you out!
Starter Motor Is Working
If the engine won’t start despite power being supplied to the starter, it’s likely due to a lack of gasoline, air, or spark (or an improperly timed spark). First, make sure the ATV has enough gasoline and that the fuel shut-off valve is open.
Is The Combustion Chamber Getting Enough Fuel?
When the throttle is wide open, and the engine is running, the carburetor mixes the air and fuel for combustion, producing power.
If the combustion chamber isn’t fed the correct quantity of air and fuel, it won’t be able to produce enough energy.
A first step would be to try starting the engine after spraying it with starter fluid and twisting the key. If it goes off, it implies the engine is not getting enough fuel to burn the air it is taking in.
If this occurs, it’s probably time to clean or adjust the carburetor (cleaning the carburetor will usually fix the problem).
Too Much Fuel
If the engine is flooded, meaning that there is an excessive amount of gasoline compared to the amount of air, the spark plug may get soaked.
The Honda user manual suggests –
You should maintain the throttle wide open with the engine stop switch and the Choke Lever off for the first five seconds after pushing the start button. Turn the switch from the off to the on position after a brief delay.
A possible cause of the flooding is restricted airflow to the carburetor.
Clearing up the air vents leading to the carburetor may solve the problem if it isn’t receiving enough air. During this operation, you should check the air filter for damage.
Check The Spark Plug
Once you’ve established that the air-fuel ratio is proper, you should double-check that the spark plug is lighting at the right moment. An in-line spark tester may be used to examine the spark.
Compression Issue
The worst possible news is that everything is running smoothly. Which is to say, there is a problem with the compression. Watch this video to resolve this issue.
Final Thoughts
At the end of the day, if the engine won’t start despite power being supplied to the starter, it’s likely due to a lack of gasoline, air, or spark (or an improperly timed spark). First, make sure the ATV has enough gasoline and that the fuel shut-off valve is open. If you have any other questions or concerns, please feel free to contact me.