No Spark 125CC By ukscooterboi (Read 2,272 times)

[ukscooterboi]

Hi guys,

As you seen the tittle i have no spark on my 125cc 4t scooter and i have been trying to research online on how to get the spark back.

New Solenoid
New Spark
New Battery
New CDI

I can only start my moped on electric button as i haven't got a kickstart.
I have cleaned the pick up coil and tried again and no spark.
I gone out and got myself a multimeter and here is the results.

[ Gray & Yellow tripy black wires into spark plug coil = 11.50 at 2M ohm ]
[ Gray and white wire = 5.36 at 2K ohm ]
[ Gray and yellow wire = 1.073 at 2M ohm ]
[ White and yellow wire = 1.500 at 20M ohm ]
[ Red and black & white wire = 80.00 at 200M V ]


I need help guys!! Please

[Deleted]

Try this...
scooterdoc.proboards.com/index.cgi?board=electrical&action=display&thread=1027

[tvnacman]

check for power and pulse .

John

[ukscooterboi]

here is my results:

hello,

Basically my scooter 125cc 4t hasn't got spark and i seen your guide and here is my results:


Next you must check the blue trigger wire that comes from the sensor magnet on top of the flywheel. It sends a small burst of energy to the CDI via the blue/yellow wire in the four plug and initiates a spark to the coil. The manuals say you need .05vAC or above to initiate the spark.

I am getting .149vAC

You should see 50 to 100vAC when you crank the motor over, here we are getting a little more than 100vAC which is fine:


I am getting 100vAC

Next you must check the blue trigger wire that comes from the sensor magnet on top of the flywheel. It sends a small burst of energy to the CDI via the blue/yellow wire in the four plug and initiates a spark to the coil. The manuals say you need .05vAC or above to initiate the spark.


I am getting .149vAC

To check your ignition switch and make sure the kill function is operating correctly, ground your multimeter and put the red lead against the black/white wire that runs to the CDI. Set your key to OFF, make sure the killswitch is set to RUN, and test for continuity, you should get a tone indicating the circuit is open which would ground out the kill wire and stop the engine; this is normal:



With key OFF i am getting .7/8ohms With key ON it cut the ohms.

Your meter should read .1 to 1 Ohm for the primary circuit, and 7 to 9 kOhms on the secondary. If you do not get these values your coil is bad and must be replaced. Due to the inexpensive nature of GY6 coils (around $10) some choose to keep a spare handy to swap out for testing purposes. I personally diagnosed my last running problem by putting in a spare coil.



Coil Primary: 00.4 ohms
Coil Secondary: 8.18/19 kohms

[rob63]

The readings look good as far as I can see. I can`t see from your first post if you`ve replaced the ignition coil/lead/cap. Also have you got a good earth between frame and engine ?

[ukscooterboi]

Jul 4, 2013 12:58:24 GMT -6 rob63 said:

The readings look good as far as I can see. I can`t see from your first post if you`ve replaced the ignition coil/lead/cap. Also have you got a good earth between frame and engine ?

I haven't replaced it but here is the results for it:

the 2 nipples green and black coil the results are: 00.4 OHMS.

Red lead on the green nipple and black on where the coil screws in = 00.3 OHMS.

Red lead on the green nipple and black on cap = 00.8 OHMS. At 20M OHMS

[ukscooterboi]

Jul 4, 2013 12:58:24 GMT -6 rob63 said:

The readings look good as far as I can see. I can`t see from your first post if you`ve replaced the ignition coil/lead/cap. Also have you got a good earth between frame and engine ?

Also I am going to explain what i can see,
I see a black cable going from the engine to frame then to the battery with a grey wire that comes from the wiring loom to the battery. is that what you mean?

[Alleyoop]

Yes, motor has to be grounded otherwise no spark.

Have you checked to make sure the cdi is not being grounded? Best way is to take the KILLWIRE off the CDI. The Killwire is the TOP WIRE on the 2 PLUG SIDE of the CDI, it is usually BLACK/WHITE stripe.
Alleyoop

[ukscooterboi]

Jul 4, 2013 13:59:40 GMT -6 Alleyoop said:

Yes, motor has to be grounded otherwise no spark.

Have you checked to make sure the cdi is not being grounded? Best way is to take the KILLWIRE off the CDI. The Killwire is the TOP WIRE on the 2 PLUG SIDE of the CDI, it is usually BLACK/WHITE stripe.
Alleyoop

Yes it has that Black/White cable, i have removed it and i have my battery on charging over tonight, so tomorrow morning i will try it and keep update.

[ukscooterboi]

Is this a common problem that Chinese scooters gets, failing at spark? But i am thinking its my Coil because i should get 1 or .1 Ohms and im getting .3/4 Ohms

the 2 nipples green and black coil the results are: 00.4 OHMS.

Red lead on the green nipple and black on where the coil screws in = 00.3 OHMS.

Red lead on the green nipple and black on cap = 00.8 OHMS. At 20M OHMS

[Deleted]

Jul 4, 2013 16:09:23 GMT -6 ukscooterboi said:

Is this a common problem that Chinese scooters gets, failing at spark? But i am thinking its my Coil because i should get 1 or .1 Ohms and im getting .3/4 Ohms

the 2 nipples green and black coil the results are: 00.4 OHMS.

Red lead on the green nipple and black on where the coil screws in = 00.3 OHMS.

Red lead on the green nipple and black on cap = 00.8 OHMS. At 20M OHMS

When reading such small values, don't forget to subtract the resistance of the test leads by touching the probes together and take a reading. The leads on my meter have .9 ohms

[ukscooterboi]

Yes i am getting .9OHMS NOW But still no spark!

[case]

Check these things.
1.kickstand/ make sure its on the center stand when firing/check kickstand switch if you have one.
2.Grounds. check all your green wires and make sure you have a clean connection to motor/frame
3.All your connections, go through them thouroghly and make sure they are all tight/disconnect them and inspect them
4.Brake saftey switch. connect together the wires leading to it to bypass it.
5. Faulty ignition is grounded/arced.
check these things
yes chinese scooters do this stuff all the time and it usually ends up being a loose wire
or something simple
good luck my man!!

[ukscooterboi]

I have changed the cap of the coil and charging my battery now later on i will put the updates.

[LUKE]

Jul 4, 2013 16:09:23 GMT -6 ukscooterboi said:

Is this a common problem that Chinese scooters gets, failing at spark? But i am thinking its my Coil because i should get 1 or .1 Ohms and im getting .3/4 Ohms

the 2 nipples green and black coil the results are: 00.4 OHMS.

Red lead on the green nipple and black on where the coil screws in = 00.3 OHMS.

Red lead on the green nipple and black on cap = 00.8 OHMS. At 20M OHMS

Yes, that is just one of the MANY common problems. ,magoo can attest to that.