The reason that there is no spark on the scooter can be due to several malfunctions. In this article we will look at how to find them, where to start searching and what to do next. The main reason that the spark on a scooter fails is usually the spark plug, or rather its malfunction. The spark plug is the main source of operation for gasoline engines. It is not difficult to check if it is faulty, but remember that you should always carry tools and a spare spark plug with you. Since the main reason that there is no spark is the spark plug, which gives the spark. So how can you check why there is no spark on a scooter ?
First, let's understand that the lack of spark on a 2t or 4t scooter has almost identical reasons.
Checking the spark plug for serviceability
First of all, to determine the serviceability of a spark plug, know where to find it.
As a rule, to do this you need to remove the plastic, for this you need to have a screwdriver. Let's assume that there are no problems with this, let's move on to the reason. The first and main check of the condition of a candle is its appearance. It should look working and in good working order, this is not difficult to determine. Minor soot is allowed. But if the spark plug is melted or black, then it is clear that it is faulty and the spark cannot flow. To determine the cause of carbon deposits on spark plugs, you need to determine whether it is wet or dry? Has the candle turned black on one side or all at once? The answers to these questions will give you the direction in which you need to “dig.” You can find out why candles turn black here.
If the spark plug is faulty, then this is the main reason why there is no spark on a 2t or 4t scooter. (2-stroke or 4-stroke). To prevent this from happening again, you need to understand why the candle deteriorated. When the mixture is too rich, it has a detrimental effect on the spark plug and the engine. You need to adjust and clean the carburetor and change the air filter and, of course, the spark plug. Thus, we found the reason why there is no spark on a 2t or 4t scooter. Replacing a spark plug will not cost as much as repairing an engine, so keep an eye on the technical condition of your scooter and undergo a technical inspection of your device at least once a season.
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No spark. Diagnostics and repair of the CDI ignition system.
Frequent questions on the forum prompted me to write this article. Let's start from the beginning, the ignition system of most scooters and mopeds, as well as small-capacity motorcycles (Minsk, Voskhod) is built on the capacitor principle, such an ignition system is called CDI (capacitor). Its operating principle is simple, the ignition coil constantly receives power from the high-voltage windings of the generator (VG), at this time the capacitor is charged, at the moment of a sudden power outage, the VV coil is short-circuited to the housing using a thyristor (key), the capacitor remains connected to the ignition coil, quickly discharging into With its accumulated charge, when the primary winding of the ignition coil (SC) is quickly discharged, the magnetic circuit of the coil (core) cannot maintain induction and dumps its energy into the winding where there is current consumption (along the path of less resistance) into the secondary winding (BB). There are 2 windings on the coil, low-voltage and high-voltage, the high-voltage is connected to the spark plug and has the property of air breakdown, therefore the energy of the magnetic circuit goes into the high-voltage winding, from it to the spark plug, at this moment a spark occurs. The function of the key to turn off the explosive coils is performed by a thyristor; the moment the thyristor is turned on is controlled by an inductive sensor. (Not Hall) The engine is stopped by a violation of the supply voltage or signal from the sensor, that is, when the sensor or explosive coils are shorted to ground, for this purpose a special wire comes out of the switch and goes to the alarm and ignition switch. That's really all you need to know.
How to check for spark
If you are not sure that the problem is precisely that there is no spark on the scooter , then you need to check. Unscrew the spark plug and insert it into the armored wire. Turn the key to start the scooter and touch the candle to any iron surface. We press the kickstarter, preferably not just once but several times, then we look at the candle. If there is no spark on the spark plug, then the guess is correct. The spark may be difficult to see in clear weather, so it is better to do it in a dark place or at least in the shade.
No spark through the ignition system
If you installed a new spark plug and the problem remains, then you are the one who is unlucky. Almost always the problem is in the spark plug itself, but there are exceptions when the ignition system is to blame. In your case there is no spark on the 2t or 4t scooter through the contacts. Check the condition of the wires and terminals, the problem is somewhere there. And be careful with the spark, because at first it is not strong, but when it goes through all the necessary stages, the voltage increases hundreds of times.
Comments
Ahi Muslim:
My scooter has a weak spark, I can't find the reason
With Your Own Hands:
wow, it’s easy for me to have a switch just like the carb
Vika Chernenko:
the sound is shit can't hear shit
Alexey Tolstikov:
I called everything about it, I pulled the spark plug 2-3 times, there was a spark, I screwed in the spark plug again, I pulled the kick, first it caught something and then there was silence, I pulled the spark plug out again, the spark was barely visible, the Chinese was half a centimeter 4x. What to do help.
Vanches201:
thank you dude, it helped a lot, I also had a problem, it was hard to start, the problem was in the switch on the tray, the switch itself went sour and drizzled, the so-called “floating error”.
Mikola Petrov:
you shit in your pants
Victor Zamkov:
Please tell me I have a 49cc Gilera moped, there is no spark, could it be a problem with the regulator or a problem with the camutator? I contacted one specialist, he says that the snout regulator has no relationship with the camutator. Is this true? The generator is new!
Chingiz Kapasov:
Could the scooter not pick up speed because of the switch?
Victor Matonin:
And if it shows not 60 volts but 30 volts, does that mean the hone coils? I have a spark but it's weak and won't start.
NoNAME BPAN:
I have an Orion 100 moped, I changed the engine to a larger one, the cubator won’t start, there is a weak spark, what should I do?
msha garbachev:
Hello! I have the same scooter as you have in the video. There is no blue wire on the four-pin pin, but green, red-white and black-yellow. None of them have 160 ohm resistance. The problem is that the spark is weak and the scooter will not start. Help me please. Thank you in advance.
Slaff4ik:
Please I need your answer. You measured the voltage on the high voltage coil of the generator when starting with an electric starter, the voltmeter showed about 60 volts, and what voltage will the generator produce when starting with a kick starter?
IVAN IVANYCH:
The fundamentals of the theory are correct and almost all are presented correctly. BUT not everything is diction. I had a hard time staying awake! But in fact, the first thing to check is the ground circuit, not only the terminal - switch, but also the switch - engine. Often the mass on the engine shows a large resistance (the bolt is not tightened, oxides, damage to the cores of the wire itself.)), accordingly, the voltage from the sensor and the supply winding will be incomplete. And most importantly, the layouts on scooters may differ! Although everything looks similar in appearance, they are essentially different. So let me add a little to the video, before we mess with the scooter, we CAREFULLY study the manuals for it!
Alexey Semenov:
Thank you for the video . Tell me, the switch receives a signal from the generator, but not from it. The switch is OK. Can a faulty relay-regulator have such an effect on the switch and the absence of a spark? Thanks again ! I have a quad – an analogue of the stealth 100 rs. Everything is absolutely the same as on your scooter.
Asker 316:
Spark plug coil wire
Asker 316:
On my scooter the coil burns out and what could be the reason.
Nicolae G:
I have such a problem with the button buzzing and turning off, the battery is draining. And with an electric drill, it wants to start but immediately stalls. When I started it the day before yesterday, there was no fuel in the filter and I got it, I just forgot to remove the spark plug, I’ll clean it today, but I don’t know what to do with the power supply. Is it possible to leak current?
Denis Rypa:
Could there be a weak spark due to the cracked magnets on the generator rotor? At idle it works and you let the gas choke and stall (who knows what?
Maxim Russ:
ok explained I'll go look at the step otherwise I have a weak spark
Oleg Babych:
and if the resistance to the magnetic induction sensor is less than 140, for example 120 for me?
What does the ignition system consist of?
Such a system on a scooter includes the following devices:
- battery
- starter
- current generator
- switch
- coil
- lock
- candle
- wiring.
Although all these elements have different sizes, costs and complexity of the device, their importance in the proper operation of motorcycle equipment is almost equal. The malfunction of just one of the above elements leads to a malfunction of the entire scooter.
Each of these devices has its own possible malfunctions. Let's discuss each device in order in which repairs should be made.
Spark plug
The most common breakdown in the ignition system (including why there is no spark on a scooter) is a faulty spark plug. The reasons are completely different: carbon deposits due to poor fuel quality (or oil); overheat; lean or enriched air-fuel mixture and others.
You can assess its condition visually by unscrewing it from the cylinder. The working color of the candle is brick. But white and black indicate problems in her work. The best way to solve the problem is to replace it with a new one. If this is not possible, then clean it with a brush, rags or heat it on a gas burner.
The spark test is carried out in the following order:
- The spark plug is unscrewed from the cylinder along with the tip.
- The spark plug body is leaned against a metal “mass”.
- The engine rotates with the crank or starter, and sparks should jump between the electrodes of the spark plug.
Remember! If a spark appears during replacement, then the ignition system is in order and you should move on to diagnosing other parts of the scooter.
Ignition coil
If the spark plug is replaced with a new one, but the scooter (moped) still does not start, we diagnose the coil. The coil is a device with two windings - primary and secondary. Visually, it is a barrel with two contacts and a high-voltage wire coming out.
The role of the coil is to increase the incoming voltage hundreds of times. The primary winding has two contacts as outputs. The secondary winding is located between the positive contact and the end of the high-voltage wire. Violation of the integrity of one of the windings leads to failure of the main task and, as a result, the absence of a spark.
It is better to start diagnosing the coil with the spark plug cap. Inside the cap there is an interference suppression resistor, which also fails. You can check it with a multimeter in resistance measurement mode. You need to connect probes to the unscrewed cap - one to the spark plug seat, the other to the end for the armor wire. The resistance is considered normal - within 5 kOhm. If not correct, replace the cap.
Electrics and electrical equipment of a scooter
Dedicated to all owners of Chinese scooters...
To begin with, I would like to present a wiring diagram for a Chinese scooter.
Since all Chinese scooters are very similar, like Siamese twins, their electrical circuits are practically no different.
The diagram was found on the Internet and is, in my opinion, one of the most successful, since it shows the color of the connecting conductors. This greatly simplifies the diagram and makes it more comfortable to read.
(Click on the image to enlarge. The image will open in a new window).
It is worth noting that in the electrical circuit of a scooter, just like in any electronic circuit, there is a common wire. On a scooter, the common wire is the minus (—). In the diagram, the common wire is shown in green. If you look more closely, you will notice that it is connected to all the electrical equipment of the scooter: headlight (16), turn relay (24), instrument panel backlight lamp (15), indicator lamps (20, 36, 22, 17), tachometer (18 ), fuel level sensor (14), horn (31), tail light/brake light (13), start relay (10) and other devices.
First, let's go over the main elements of the Chinese scooter circuit.
Egnition lock.
Ignition switch (12) or “Main switch”. The ignition switch is nothing more than a regular multi-position switch. Even though the ignition switch has 3 positions, the electrical circuit uses only 2.
When the key is in the first position, the red and black wires are connected. In this case, the voltage from the battery enters the electric circuit of the scooter, the scooter is ready to start. The fuel level indicator, tachometer, sound signal, turn relay, and ignition circuit are also ready for operation. They are supplied with power from the battery.
If the ignition switch malfunctions, it can be safely replaced with some kind of switch like a toggle switch. The toggle switch must be powerful enough, because the entire electrical circuit of the scooter is, in fact, switched through the ignition switch. Of course, you can do without a toggle switch if you limit yourself to short-circuiting the red and black wires, as the heroes of Hollywood action films once did
In the other two positions, the black and white wire from the CDI ignition module (1) is shorted to the housing (common wire). In this case, engine operation is blocked. In some scooter models, to block the engine, there is an engine stop button (27), which, like the ignition switch, connects the white-black and green (common, body) wire.
Generator.
The generator (4) produces alternating electric current to power all current consumers and charge the battery (6).
There are 5 wires coming from the generator. One of them is connected to a common wire (frame). The alternating voltage is removed from the white wire and supplied to the relay regulator for subsequent straightening and stabilization. The yellow wire removes voltage, which is used to power the low/high beam lamp, which is installed in the front fairing of the scooter.
Also in the design of the generator there is a so-called hall sensor. It is not electrically connected to the generator and there are 2 wires coming from it: white-green and red-black. The hall sensor is connected to the CDI ignition module (1).
Relay regulator.
Regulator relay (5). People may call it a “stabilizer”, “transistor”, “regulator”, “voltage regulator” or simply “relay”. All these definitions refer to one piece of hardware. This is what the relay regulator looks like.
The relay regulator on Chinese scooters is installed in the front part under a plastic fairing. The relay-regulator itself is attached to the metal base of the scooter in order to reduce the heating of the relay radiator during operation. This is what the relay regulator looks like on a scooter.
In the operation of a scooter, the relay regulator plays a very important role. The task of the relay regulator is to convert the alternating voltage from the generator into direct voltage and limit it to 13.5 - 14.8 volts. This is the voltage required to charge the battery.
The diagram and photo show that there are 4 wires coming from the relay-regulator. Green is the common wire. We have already talked about it. Red is the output of positive DC voltage 13.5 -14.8 volts.
The regulator receives alternating voltage from the generator through the white wire to the relay. Also connected to the regulator is a yellow wire coming from the generator. It supplies the regulator with alternating voltage from the generator. Due to the electronic circuit of the regulator, the voltage on this wire is converted into a pulsating one, and is supplied to powerful current consumers - the low and high beam lamps, as well as the dashboard backlight lamps (there may be several of them).
Reasons for the loss of spark (video)
How else can you check for a spark? Find out from this video:
From the article you learned why there is no spark on a 4t scooter and the reasons for such a malfunction. The cost of repair work may vary depending on the cost of the parts, but it is always more profitable to do the work yourself. And now you know what to do if the spark suddenly disappears; what to pay attention to. Be careful when troubleshooting, pay attention to details, refer to reference books for accurate data. Only if all conditions are met will you succeed!
Why is there no spark on my scooter?
There are different types of scooter breakdowns, and if you notice that it simply won’t start, you should start looking at the fault in the most common parts. One of these is the spark plug.
The spark plug is the main source from which any vehicle runs and so if you see that your scooter has gas but is still broken, check the spark plug. In any case, you should carry tools with you. Also, be sure to stock up on an extra spark plug so that if the main one breaks, you can immediately replace it. But how can you determine the condition of such an important scooter part?
A dead battery is a common problem.
If the scooter does not start from the starter, try starting it from the kick starter. The most common problem is that the battery is simply dead due to a long period of inactivity, or has reached its intended service life. But it also happens that the relay regulator fails or the fuse blows. The fuse is usually transparent and its demise can be determined by eye. A malfunction of the regulator relay can be determined by starting the scooter with a kick starter and measuring the voltage at the battery contacts. It should not exceed 14.5 V. To avoid discharging the battery in the future, we advise you to remove the negative terminal, and during winter idle time, keep the battery warm, check the electrolyte level and fully charge it before storage.
If you want to upgrade your scooter, then you will be interested in the article tuning a scooter with your own hands.
Condition of the spark plug and its malfunction
The simplest way is external verification. If it has a normal color and looks natural, the part is most likely working. Signs of use such as erosion and sediment from long-term use are acceptable. When a vehicle's fuel mixture becomes too rich, the result affects not only the engine, but primarily the spark plug itself. Thus, black dry deposits appear in some areas. , as well as replacing the air filter, will help correct the situation Do not use a dirty or damaged spark plug, otherwise the engine will not operate properly and will soon need repairs. This is one of the reasons that answers the question of why there is no spark on the scooter ?
There have also been many cases when the wrong amount of oil entered the engine, which contributed to the contamination of the spark plug. It is easy to distinguish carbon deposits from oil contamination; examples are in the photo. And according to statistics, such malfunctions occur precisely with 2t scooters that have an oil pump. Immediately replace the spark plug in the oil with a new one.
Spark plug diagnostics
The first thing to do if there is no spark on the quad is to check the spark plug. Most often, the problem arises precisely because of this component. The owner of the equipment needs to unscrew, clean the spark plug from carbon deposits, and screw the element back in.
You also need to inspect the electrode. A working candle should have a light brown color. Any deviations from the norm (black or white tint, oily reflections, etc.) indicate problems in a particular system.
In fact, checking the performance of a candle is quite simple. You just need to insert one end of the candle into the cap, and touch the engine with the other. After this, you need to turn on the ignition and crank the crankshaft. If there is no spark, then the spark plug needs to be replaced.
Note: The problem may not be with the spark plug, so the rider should perform a reference test with a working spark plug.
Another reason why there is a weak spark on a children's ATV is a broken spark plug cap. First you need to disconnect the component and dry it. Checking the cap is performed in the same way as diagnosing a spark plug.
How to check the spark on a spark plug?
If you have never checked a scooter's spark plug for a spark, then this procedure is more than simple. You need to unscrew the spark plug itself from the cylinder and insert it into the armored wire (connected to the spark plug). Then turn on the ignition of the scooter and touch the spark plugs to any iron surface. Press the kickstarter several times and look at the candle. If there is a spark, the ignition system and the spark plug itself are fully functional. In sunlight the spark may not be visible, so choose a dimmer light.
No spark due to ignition system
Let's say you put in a new, unused candle. In most cases the problem should be resolved, but there are exceptions. If you are that unlucky moped owner, you should move on to the next equally popular reason for the lack of a spark - the ignition system. Usually there is no spark on the scooter due to the contacts. To ensure the contacts are working, check that the terminals are secure and that the wires are in good condition. And then comes the most difficult part - the electrical circuit of the scooter.
The process of generating a spark is quite complex, because first the electric current must go through several stages, the first of which is the generator. Next, the current enters the switch, accumulating in the capacitor. At first, the spark arrives at a small voltage, but once it goes through all the stages, eventually passing through the ignition coil, the voltage increases hundreds of times. That is why, when checking the ignition system, never touch the place where the spark appears.
Scooter ignition system
Any scooter has a wire installed that turns off the engine. It usually runs from the switch to the scooter's ignition system. As soon as you turn off the engine, the wire extinguishes the spark. If you suspect that there is no spark due to the wire, you can check this as follows: first you need to find the “-” ground on the ignition coil and the “+” going to the switch. The second contact (to the switch) should be disconnected, and then you can check the resistance of the remaining wire, which is located between ground and contact. The field needs to check the resistance between ground and commutator accordingly. If you are not at all knowledgeable about coils and electricity, it is highly recommended that you seek expert advice.
These are two common causes of breakdowns, so you should pay attention to them. Also, the lack of a spark may be due to trivial reasons, such as an armored wire that is not fully connected or a faulty piston group. Therefore, keep an eye on the condition of your scooter and such breakdowns will not happen to you.
Malfunctions in the power system
If there is a spark, but after that the scooter does not start, there is a high probability that fuel is not supplied. To address this issue, start checking at the gas tank. It is advisable if the gas tank is at least half full. To ensure that fuel is supplied to the carburetor, remove the fuel hose from the carburetor by lowering it into a previously prepared container (bottle).
Are all settings normal? But why won't the alpha moped start? See all possible faults!
As a rule, scooters have a built-in vacuum gas valve that opens the fuel supply only during startup or operation of the scooter. To check the valve with the fuel hose lowered into the bottle, we try to start the engine for 3-5 seconds, or until a stream of gasoline appears. In this case, the stream must be constant, at least “as big as a match”. If there is gasoline, but does not flow, the gas valve must be replaced.
If it is working, we look for the cause in the carburetor. First, the air filter must be clean. Because if there is a leak at the junction of the carburetor with the intake pipe, air is sucked in there, the mixture becomes too lean and starting the engine will be impossible. Make sure the gaskets between the carburetor are intact. Let's go further, the reason may be in the carburetor itself.
What to do if there is no spark on the scooter?
Your scooter's engine suddenly stops, what should you do? Don't rush to panic. First, check if there is gasoline in the tank. If the reason is not due to running out of fuel, the problem must be looked for in the ignition system. The first thing that comes to mind is that the spark plug has gone bad. In this case, it is recommended to have a working candle in stock.
By the way, you can determine the condition of a candle by its appearance. A normal candle has no external changes. Minor electrode erosion and small deposits are acceptable on its surface. If you see the formation of dry black carbon deposits on the spark plug elements, it means that carbon contamination has occurred as a result of an overly enriched fuel mixture. The spark plug should be cleaned or replaced, and the working mixture adjusted. The air filter will also need to be replaced.
Overheating can result in melted electrodes and bubble formations on the insulator. Using such a spark plug can cause serious damage to the engine.
Another cause of spark plug malfunction can be oil contamination. The appearance of such a candle is clearly visible in the photograph. Typically this occurs in two-stroke engines. These spark plugs need to be replaced.
Spark plug condition
So, install a spare spark plug and start the engine. Did it work? Great! But if there is no spark on the scooter, but the spark plug is working, most likely the problem is in the ignition system itself. Therefore, we will have to look further for the reason.
The simplest and most accessible reason for self-repair may be lack of contact. In order to find out, we check the connection points of the terminals and the integrity of the wires.
Then we begin to study the electrical circuit: electric current flows from the generator to the switch, accumulating in the capacitor. The latter transmits a signal to the ignition coil, where the voltage increases several thousand times and, traveling along a high-voltage wire, enters the spark plug, bypassing the cap. Be careful not to touch your finger to the area where the spark should come from - this is a high voltage area.
A wire is pulled from the electromagnetic sensor in the engine or from the switch to the ignition switch to turn off the engine. When the engine is turned off, the wire shorts to ground and the spark goes out. To check whether this is the reason for the lack of a spark, you should find two contacts on the ignition coil: ground “-” and on the switch “+” (do not confuse it with a high-voltage wire!). The contact going to the commutator is disconnected, after which the resistance between the ground and the coil contact is checked, and then between the ground and the commutator.
Scooter engine
During normal operation, there should be a lot of resistance in both cases. If the resistance on the coil is insufficient, it needs to be replaced, and if the resistance on the wire is low, most likely the reason is in the switch.
If the above steps do not reveal any defects, most likely the problem is in the electromagnetic sensor or generator. These items are checked depending on the scooter model.
Find a black wire with a red stripe in the switch connector and measure its resistance relative to ground. Normally, it is 500 Ohms - this is a check of the sensor’s operation. Next, we check the resistance of the supply winding wire - often it is a blue wire with a white stripe. The resistance should be 150-200 ohms. Significantly lower resistance indicates an internal short in the supply coil, resulting in insufficient voltage to spark.
If, when checking, all of the listed elements operate normally, the switch is most likely faulty. To check its operation, you will have to go to a workshop, since this is impossible to do in a garage.
Main elements of the system
Of course, the first thing to mention is the spark plugs. They are installed in the cylinder head, the electrodes come out from the inside. These are the elements that allow the air-fuel mixture to ignite. But with the help of spark plugs alone, the engine will not be able to run. It is necessary to monitor the position of the crankshaft in order to know in what position the pistons are in the cylinders.
For this purpose, an inductive sensor operating on the Hall effect is used. It is part of the design of another element - the ignition distributor. The sensor produces a pulse that is sent to the switch. This device allows you to amplify a weak signal to a voltage of 12 volts, and then apply it to a coil. A coil is nothing more than a simple transformer (step-up). Its secondary winding has a greater number of turns than the primary. Due to this, the voltage increases and the current decreases. The voltage in the BSZ is supplied to the spark plugs at a value of 30-35 kV (depending on the car model).
