Generally speaking you will want to replace the spark plug(s) after each 100 hours of use. This assumes of course that your engine is running normally and you are not experiencing problems like a "rough engine" or an engine that fails to catch while the ignition is turning over. If these occur it's time to pull the plug and determine if it is the problem or some other component is the cause.
Actually pulling the plug, inspecting and replacing it only takes 5 to 10 minutes. However, unlike a car you can't pull a handle and pop the hood to get to the spark plug. On an ATV you have to remove plastic (exterior panels) to expose the plug and depending on your brand that could be a lot of plastic. Pulling off parts is the real time consumer for this task.
Because it takes a bit of work to "open up" your ATV it's a good idea to check a couple of items while they are easily accessible. Make certain that the bolts on the battery cables are firmly attached to the battery posts. A common "won't start" problem is often the result of hard riding loosening the bolts from the battery terminals.
Your exhaust system is another component that is accessible in most models when you have sufficient exterior panels removed to get to the spark plug. Check the bolts holding the pipe to the engine to ensure a secure fit.
The steps we provide below are general in nature and are not meant to replace the instructions found in your OEM owner's manual. Obviously different brands have different engine mounting configurations meaning the location of the spark plug and how easy it is to access will vary. When in doubt, follow the OEM instructions. Our tips are intended to show you that this repair can be done as a DIY project saving you professional labor costs and a more enjoyable ATV experience.
Replacing the spark plug is a simple DIY task that almost anyone can accomplish in a minimal amount of time.
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In many ways, the spark plug in your ATV is its beating heart. Not only does the spark plug start the engine in the first place, but it also keeps firing a spark every revolution of the engine (or every second revolution if you have a four-stroke).
Electrical energy is sent through the spark plug, causing a spark of electricity to jump the small gap if the voltage is high enough. This spark is in the perfect position to ignite the mixture of gas and air in the combustion chamber.
The importance of the spark plug to your ATV, UTV, or snowmobile’s operation means when something goes wrong with it, you’ll know pretty quickly. Spark plugs that appear white have likely been overheating. Those that are yellowing are typically affected by rust. These issues can be resolved by replacing the spark plug.
But what if your spark plugs keep turning black? This is an interesting conundrum, as there are a few possible reasons for charred or dark spark plugs. In this article, we’ll look at the top reasons your spark plugs are turning black and how to stop it from happening again.
Engine flooding occurs when fuel sits in the engine without being burnt. When the engine floods, this fuel can reach the spark plug, causing it to blacken and ultimately stop working as required.
It’s pretty easy to flood an ATV, UTV, or snowmobile engine if you’re not careful. Starting up the engine and then immediately stopping it often results in flooding because the fuel hasn’t had time to be burned. In this case, your vehicle may refuse to start up because the spark plug is covered in fuel.
For a quick fix, you can remove the spark plug and clean the area of fuel. Dry off the spark plug, and you should be back in business. You may be better off simply replacing the spark plug with a new one, though, to ensure it will work perfectly.
You can release the drain screw of the carburetor to drain all the fuel from the carb. If the engine is flooding due to a mechanical failure, you’ll need to get to the bottom of the issue. But removing and cleaning a carb is a relatively complex affair.
Inside the carb, the float level is critical to flooding. Too high, and the pilot circuit will be flooded with fuel. Too low, and the main jet lacks fuel at high speeds. The float level has a particularly low tolerance, often 1.5-2.5mm but sometimes only 1mm.
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Another culprit for black spark plugs is an oil leak. Oil can make its way to the spark plug through a faulty gasket, worn washers, or old O-rings.
If you can’t find the leak there, the valve guides or piston may be leaking oil. You’ll need to replace the part that’s leaking oil and replace the spark plug that’s been compromised.
If your carburetor is running too rich (i.e., too much gas), then this can cause calcium deposits to build up on the spark plug. If your mixture is too rich, you’ll likely also be noticing other symptoms, such as excessive black smoke from the exhaust.
These carbon deposits are a pain because electricity always seeks the path of least resistance, and carbon is an excellent conductor! The electricity will no longer be performing its duty to spark the gas correctly, resulting in poor performance overall.
Though there are a few reasons your fuel mixture could be too rich, in this case, the most likely cause is old engine oil. If you leave too much time between oil changes, you’ll see the results of the neglect here at the spark plug (alongside damage to other mechanics).
Resolve the issue by replacing your engine oil. New oil will break down the built-up carbon, so it gets stuck in the oil filter. And remember to keep changing your oil regularly.
In general, expect to replace spark plugs every 100 hours you ride your vehicle. As usual, this is just a general guideline, as hard riding or a hot climate can prematurely put a spark plug out of commission.
Thankfully, spark plugs are relatively inexpensive, and it’s easy to change them yourself. First, remove the spark plug wire by hand. Take a wrench to unscrew the old spark plug, and use it again to install your new spark plug, ensuring it’s tight.
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At first glance it seems that ATV spark plugs are small parts. But they are responsible for igniting the fuel mixture and starting the ATV. In addition, the candle is a kind of "indicator" of the health of the equipment, and can inform the rider about a number of malfunctions. Therefore, it is important for the driver to know when, after buying an ATV, to change this component and how to do it correctly.
The spark plug is basically a consumable item. The technical documentation for the device indicates the manufacturer's recommendations when to change this component. On average, the "life" of a candle is 6-8 thousand km. However, it all depends on the condition of the ignition element. The following can reduce the life of a component:
Damage to the element will cause a number of problems. For example, if the rider noticed that there was no spark on the ATV spark plug, it became difficult to start the engine, fuel consumption increased, or the engine started to work incorrectly, you need to change the spark plug. nine0003
It should be noted right away that the resource and operation of a spark plug directly depends on its quality. Therefore, drivers should only buy proven products from well-known brands. Agree, it is easier to buy a good component that will last 8 thousand km than to buy a new part every 1.5-2 thousand km.
There are also a number of parameters to consider when choosing a new component for the ignition system. The key role is played by the dimensions of the candle itself (thread diameter and its length). You need to pay attention to the heat number. This is also an important parameter, ignoring which can lead to uncontrolled ignition of the fuel mixture upon contact with soot or hot engine elements. nine0003
To avoid problems, a special marking is applied to the plug, which indicates the permissible temperature of the component and its resistance to pre-ignition. This is a really important characteristic, because the piston is destroyed due to uncontrolled ignition.
Low spark plug temperature will also damage your ATV. If you buy a component with too high a heat number, carbon formation will increase and the engine will lose power.
Most often, on the market you can find candles with glow number:
Before you buy a spark plug for a children's ATV or an adult ATV, always study the technical documentation. The instructions usually indicate the optimal parameters of all consumable components.
It is important to note that in order to change the spark plug, you will have to remove part of the ATV's bodywork. In almost all quadrics, the component is covered with plastic parts and even accessories (gas tank, etc.).
After you have dismantled the body part, you need:
After this, inspect and clean the spark plug (if you intend to continue using it). Inspection of the component should not be ignored, as it will help to detect problems in the operation of the ATV.
By the type of spark plugs on the ATV, you can determine the serviceability of the equipment. For example, if:
And these are only the most common "diseases" that can be diagnosed with a spark plug.
02/19/2021 2066
Sent by 19 December 2011 - 20:56
Who doesn't want to make their ATV more powerful for free? And if you can do it yourself and very quickly, that's even better! nine0095
Today we're going to talk about spark plug "indexing", which has long been familiar to motor racing drivers, but whose benefits have not been proven for ATVs until recently.
The process is extremely simple: the spark plug must be installed so that the spark forms in the optimal place for combustion. The only problem is that amateur mechanics cannot agree on a common opinion in any way, whether the electrode, and, accordingly, the candle, should be located facing the intake valves or the exhaust valves. nine0095
We ran some experiments on the KTM 450XC and Suzuki LTR450 ATVs and on both machines we were able to get a slight boost in power when the plugs were about ¾ facing the exhaust valves.
How to place the candle in the desired position? First you need to remove the spark plugs and mark the location of the electrode on their top with a regular marker. Then you just need to put the candles in place and turn them in the right direction, slightly loosening or tightening their fasteners. nine0095
If you want to turn the spark plug in any direction more than a quarter of a turn, you risk too strong or too weak a fix
Post has been editedGrim: 19 December 2011 - 21:08
Sent by 19 December 2011 - 22:38
I have one question: isn't one of the electrodes on the spark plug in the center?
And it seems to me in which direction the negative electrode is before the bath, the main thing is the uniformity of combustion (ignition) of the working mixture in the combustion chamber and here the main location of the spark occurrence zone in the volume of the combustion chamber. IMHO
Submitted by 20 December 2011 - 11:43
The main thing is not to overtighten and not drown! And everything else is poof
Submitted by 20 December 2011 - 12:21
IMHO some kind of nonsense.
And if you run around the quadra twice with a shaman's tambourine, then you can achieve better controllability...
Post has been editedGrim: 20 December 2011 - 12:21
Submitted by 20 December 2011 - 13:02
In short, you need to buy 10 pieces of candles and one CAN be!! will be in the right position
The rest - "Into the abyss"))))))
for both machines, we were able to achieve a slight increase in power when the candles were located about ¾ facing the exhaust valves.
It’s better to immediately put the “homogenizer” of the mixture))))))
But if you don’t reach the candle in pursuit of ¾ face or worse, the thread will float from constriction, that will be grief. I do not believe that the increase in power in this case can be FELT.
Sent by 20 December 2011 - 14:18
The very name of the topic is provocative. For some reason, I immediately thought that we would talk about things at the level: to withstand preliminary candles inside a pyramid oriented by parts of the world with edges or there lighting candles with moonlight in certain phases of the Moon / Mercury / Venus and similar things ... In general, 4- x electrode candles. Use it to your health, although they do not give any fundamental innovations such as a noticeable increase in power (unless, of course, the old candles were completely bad). nine0095 And be sure to pay attention to the completely correct remark above, that both constriction and undertightening of candles during installation is fraught with consequences!
Sent by 20 December 2011 - 17:42
SPARCO mudguards add more power
Sent by 20 December 2011 - 18:15
But only light green! Other colors do not give a tangible result!
Sent by 20 December 2011 - 21:24
Did you even look at the link? There's plenty of good advice in there too.