Here’s a tutorial on what to do if your motorcycle engine is flooding

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We often have to deal with problems with our motorcycles at the most inconvenient times. Flooded engines are not uncommon and can happen to any motorcycle.

Though a flooded motorcycle engine isn’t enjoyable to deal with, it’s actually quite possible to take care of it yourself in the comfort of your own garage or driveway with some simple tools.

What do you do if the motorcycle engine has flooded? First, wait for 15 minutes until the fuel in your motorcycle engine has dried out. If that doesn’t work, turn off the petcock, remove the ignition coil fuse, remove the spark plugs, place rags slightly inside the spark plug holes, and crank the engine to let the excess gas squirt on the rags.

Most of the motorcycles I’ve owned had a flooded motor. I’ve been able to perform this flooded engine fix several times and it has proven to work well. In addition to knowing how to repair a flooded motorbike engine, I can also tell you about other things that could be helpful.

How to Repair a Flooded Motorcycle Motorbike Engine

I have experienced a number of flooded motorcycles. The first time it happens, it can be scary. The term “flooded engine” doesn’t sound right, in fact it almost sounds detrimental to the motorcycle.

In most cases, a flooded motorcycle engine shouldn’t cause too much alarm. It’s a pretty common occurrence and can easily be taken care of if the right steps are taken. Like I said before, I’ve done this a handful of times myself and started out doing so as an amateur; everything turned out just fine.

If you’ve found yourself with a flooded motorcycle engine, First, stop trying to get it started and let it sit for 15 minutes. This will allow fuel to drain and dissipate.

There are some who worry about the possibility of the accumulated gas in a flooded engine leaking past the piston rings. When this happens, the gas mixes with the oil that’s inside the engine.

While it’s possible for some of the gas to drain past the piston rings, it’s not too much cause for alarm because the very small amount that does drain and mix with the oil will not be enough to change the consistency of the oil. You can change your oil if you’re concerned about it.

A flooded motorcycle engine can cause excessive gas to drain past the piston rings, and may mix with the oil within the engine. If this does happen, that’s due to a faulty piston ring because it shouldn’t be letting that much gas past it. A damaged piston ring could also cause excessive oil consumption.

So unless your motorcycle has been burning a lot of oil, you won’t need to worry about the gas seeping into parts of the engine it shouldn’t. You can wait while the gas builds up in the cylinder is vaporized through the open valves.

If you’ve waited at least 15 minutes and attempted to start the motorcycle only to find yourself flooding the engine again or the gas hasn’t seemed to have dissipated, you’ll need to resort to plan B which is emptying the cylinders yourself.

To do this, the first thing you’ll need to do is turn off the petcock. This will stop you from adding fuel to your engine every time you crank it for a few more minutes. The next thing is to (and it’s very important you do not skip this step) The fuse that connects to your ignition coil must be removed.

Others say that the ignition coil fuse should be removed, but I disagree. It is possible that you are still receiving current from your ignition coil, which runs through the spark plug wires. You don’t know what those dangling wires (or dangling spark plugs if they’re still connected to the wires) will touch while you’re fixing this problem and it could result in you getting shocked or possibly grounding to the gas tank.

After you’ve removed the ignition coil fuse, remove the spark plugs and examine their condition. You must ensure that there is no corrosion and that the electrode gap (the distance between the spark plug’s end and the hook at its end) is correct.

Next, take a few cloths and place them in the spark plug holes. It’s important you don’t stuff them in there because when you go to start the engine, the compression will just blow them out and gas will spray. Place them in a way where they’ll be able to catch the spraying gas but there’s also room for air to pass them.

You can now crank the engine. The pistons will push the gas from the spark plug holes into your cloth. After a few minutes, crank the engine until the cloth is pulled out of the spark Plug holes. “on,” Start your motorcycle.

What Causes a Flooded Engine

You may have encountered a flooded motorcycle a few times throughout the time you’ve owned your motorcycle. Or perhaps you’ve simply heard about other people having the issue. It happens. However, many people are curious about how the engine of a motorcycle floods.

When the fuel is not properly injected into the cylinder, the motorcycle engine can become flooded. There is no spark to ignite it. The carburetor, or fuel injector, keeps pumping in more fuel. However, there is no spark to ignite it. So the fuel stays in the cylinder until it fills up. “floods” it.

It eventually gets to a point that even if there was a spark that happened with all that fuel built up, the fuel wouldn’t ignite because the air to fuel ratio is so far off. There is literally no space left for air to enter to create the proper mixture necessary to cause combustion.

In short, the main reason a motorcycle engine floods is because of faulty spark plugs that aren’t providing the spark the engine needs to combust. Spark plugs are simple parts, but if everything on them isn’t just right it can cause a slew of problems such as this.

Problems with the spark plug wires and ignition coil could also be at play. If the ignition coil is malfunctioning, it won’t send the right signal through the spark plug wires and tell the spark plugs to spark. The spark plug wires could also be worn out or damaged, which can cause the spark plugs to not get a spark.

How to tell if your problem is a flood engine

A motorcycle not starting could be caused by hundreds of reasons, so it’s sometimes hard to know if a flooded engine is your culprit. A flooded engine could be a sign that something is wrong.

Obviously, the first symptom will be that your motorcycle won’t start. The starting mechanism will sound perfectly normal, but that the combustion just isn’t happening.

A sudden smell of gas is the second sign that your engine may be flooded. Because gas is building up in the cylinders, you’ll easily be able to smell it. A third sign you should look out for is fuel leaking or spraying from the exhaust pipe. Some water may have built up inside the pipes, so if they’re spraying any liquid make sure it is gas that it’s spraying.

If you have all three of these symptoms, chances are the reason your motorcycle isn’t starting is due to a flooded engine. If you have more evidence of your engine flooding, there are some things you can do.

Because a flooded engine is due to a lack of spark from the spark plug, you can actually check the spark plugs themselves and see if they’re giving a spark. You will need to remove the sparkplug wires from your engine. Once the sparkplug wire is removed, you can reinstall it into a sparkplug wire. “dangling”).

You’ll then need to touch the end of the spark plug to the engine or frame (the hook end) so it becomes grounded. Be very careful with where you ground it; you don’t want to ground it near or on any gas or any flammable chemicals. Never ground the spark plug wire to the motorcycle tank.

Once the sparkplug is grounded, with the wire still connected to it, press the starter button. Make sure your fingers are away from the spark. If the spark plug does spark, you’ll know the spark plug isn’t working. This can be done on all spark plugs. If all of them don’t work, you likely have an ignition coil issue. If some work and some do not, you’ll need to replace all the spark plugs.

How to Prevent a Motorcycle Engine from Flooding

Like I said before, encountering a flooded engine is annoying and you probably don’ want to ever deal with it again. There are steps you can take to prevent your motorcycle from flooding.

Misfunctioning spark plugs are the primary reason why a motorcycle engine floods. It is important to maintain the health and performance of your motorcycle’s spark plugs. You’ll need to examine your spark plugs at least once a year and replace any if they look less than functional.

A lot of people don’t understand the importance of the spark plug gap at the end of the spark plug (the distance between the spark plug and the electrode at the end, or the hook looking part). Many people buy a sparkplug from an auto shop and then place it in the sparkplug hole. While this will work for a while, it won’t be as efficient in the long-run.

You must ensure that the spark plug gap is correct when you purchase it. An auto parts shop will sell a spark gap instrument for just a few dollars. You’ll need to look in your owner’s manual or look online about what the appropriate gap space needs to be on each spark plug in your motorcycle and make the appropriate changes to it using your tool. Spark plugs are not supplied with the correct gap for each vehicle.

Along with regular spark plug maintenance, you’ll also want to regularly check the condition of your spark plug wires as well. You should replace any cracked or brittle spark plug wires immediately as they could allow the current to arc onto the motorcycle instead of the sparkplug.

Similar Questions

How do you know if your motorcycle’s engine has seized? An electric starter engine that is in good condition will click, but not rotate, if the starter and battery are in good health. The piston seizure will cause the kick pedal to stop moving on a kick starter engine. For more information, click here.

What are some other reasons a motorcycle won’t start? Some reasons a motorcycle won’t start can include a dead battery, blown fuses, a clogged injector, a bad starter, engine timing is off, or clogged jets in a carburetor. My article contains more information about starting issues.

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