TaoTao No spark
#33
06-30-2015, 11:26 PM
Electrical Expert
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Actually not, Jaster. You out numbered my posts by far. By word count maybe I win, but most of mine was cut and paste from earlier posts.
Our troubleshooting techniques are quite different, but I think they compliment each other.
I suspect that many would rather submit to an afternoon of eye surgery rather than try to use a meter to solve their problem. If trial and error is able to fix the problem, then that's good. If not, there is always the meter approach - even if it resembles eye surgery....I too am happy that 2x_lung was able to solve the problem.
#34
06-30-2015, 11:50 PM
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I'm glad you got it working...
Most pickup coils are not adjustable. Since you have an adjustable one, keep in mind that there is such a thing as "too close". There is a raised steel bump on the flywheel that passes underneath the pickup coil in close "fly by". If it is too far out you never get a trigger pulse to fire the CDI (i.e. you don't get spark). If it is too close the raised bump will hit the pickup coil and be quickly destroyed. Hitting may only happen once the engine gets fully warmed up.
I don't know the spec's for your engine, but every spec I've seen for other engines specify 0.020" to 0.025" clearance between the pickup coil and the raised steel bump on the flywheel. If you don't have a feeler gauge, take a dollar bill and fold it in thirds. Then double it over again to get a bill that is six layers thick. That is 0.023" (close enough). Use that as a spacer to set the clearance between the pickup coil and the raised bump.
In case anyone is wondering how this works:
That raised steel bump is not a magnet. It is just a raised bump of steel. The magnet is stationary and recessed inside the pickup coil itself. It is arranged inside a shielded tube with an opening on the end such that the pickup coil can't see more than a few tens of thousands of an inch outside of the pickup coil. If you think about it, this is completely necessary to keep the pickup coil from seeing the powerful embedded magnets that generate the 12 volts battery charging circuitry.
The raised bump of steel bends the magnetic field in the pickup coil one way as the leading edge approaches, then bends it the other way as the trailing edge passes. This generates a plus/minus voltage pulse pair out of the pickup coil. The first arms the CDI, and the second fires the CDI.
Most pickup coils are not adjustable. Since you have an adjustable one, keep in mind that there is such a thing as "too close". There is a raised steel bump on the flywheel that passes underneath the pickup coil in close "fly by". If it is too far out you never get a trigger pulse to fire the CDI (i.e. you don't get spark). If it is too close the raised bump will hit the pickup coil and be quickly destroyed. Hitting may only happen once the engine gets fully warmed up.
I don't know the spec's for your engine, but every spec I've seen for other engines specify 0.020" to 0.025" clearance between the pickup coil and the raised steel bump on the flywheel. If you don't have a feeler gauge, take a dollar bill and fold it in thirds. Then double it over again to get a bill that is six layers thick. That is 0.023" (close enough). Use that as a spacer to set the clearance between the pickup coil and the raised bump.
In case anyone is wondering how this works:
That raised steel bump is not a magnet. It is just a raised bump of steel. The magnet is stationary and recessed inside the pickup coil itself. It is arranged inside a shielded tube with an opening on the end such that the pickup coil can't see more than a few tens of thousands of an inch outside of the pickup coil. If you think about it, this is completely necessary to keep the pickup coil from seeing the powerful embedded magnets that generate the 12 volts battery charging circuitry.
The raised bump of steel bends the magnetic field in the pickup coil one way as the leading edge approaches, then bends it the other way as the trailing edge passes. This generates a plus/minus voltage pulse pair out of the pickup coil. The first arms the CDI, and the second fires the CDI.
Well guys, I wanted to give you all a huge THANK YOU. I was able to figure out why I wasn't getting spark. This is why.....
So I pulled the left side cover. I was thinking....man, I've replaced all the electrical and it has to be the stator. As I was looking inside the cover and at the rubber piece with the round contact on it, I thought.....maybe it's not close enough to the flywheel to get the magnetic charge. So I took a flathead screwdriver and bent(pryed) it out toward where it would be closer to the flywheel. I put it back on the quad, hit the starter and BAMMMMM....Tons of spark. I secured it back on the atv, put the plug back in and....BAMMMMMMMMM....ran like a champ. I killed it and couldn't get it to start again.
Well, I took the cover back off. There are two screws with adjustment to make the rubber contact closer to the flywheel. I loosened them, moved it toward the flywheel and reassembled. BAMMMMMM.....ran perfect since. It starts with an ever so light "tap" of the starter switch!!!
Just wanted to post my findings unless this happens to someone else...thanks so much guys.
So I pulled the left side cover. I was thinking....man, I've replaced all the electrical and it has to be the stator. As I was looking inside the cover and at the rubber piece with the round contact on it, I thought.....maybe it's not close enough to the flywheel to get the magnetic charge. So I took a flathead screwdriver and bent(pryed) it out toward where it would be closer to the flywheel. I put it back on the quad, hit the starter and BAMMMMM....Tons of spark. I secured it back on the atv, put the plug back in and....BAMMMMMMMMM....ran like a champ. I killed it and couldn't get it to start again.
Well, I took the cover back off. There are two screws with adjustment to make the rubber contact closer to the flywheel. I loosened them, moved it toward the flywheel and reassembled. BAMMMMMM.....ran perfect since. It starts with an ever so light "tap" of the starter switch!!!
Just wanted to post my findings unless this happens to someone else...thanks so much guys.
#35
07-01-2015, 06:09 AM
Actually not, Jaster. You out numbered my posts by far. By word count maybe I win, but most of mine was cut and paste from earlier posts. Our troubleshooting techniques are quite different, but I think they compliment each other. I suspect that many would rather submit to an afternoon of eye surgery rather than try to use a meter to solve their problem. If trial and error is able to fix the problem, then that's good. If not, there is always the meter approach - even if it resembles eye surgery.... I too am happy that 2x_lung was able to solve the problem.
I suspect that many would rather submit to an afternoon of eye surgery rather than try to use a meter to solve their problem. If trial and error is able to fix the problem, then that's good. If not, there is always the meter approach - even if it resembles eye surgery.... I too am happy that 2x_lung was able to solve the problem.
#36
07-23-2018, 06:41 PM
#37
11-28-2022, 02:03 PM
Chinese Quad no spark solution
After installing 2 new wiring harness's and getting no spark but plenty of frustration..... this was the solution! I moved the pickup closer to the steel bump and boom! Spark!!!!
Thanks for the knowledge.
Thanks for the knowledge.
I'm glad you got it working...
Most pickup coils are not adjustable. Since you have an adjustable one, keep in mind that there is such a thing as "too close". There is a raised steel bump on the flywheel that passes underneath the pickup coil in close "fly by". If it is too far out you never get a trigger pulse to fire the CDI (i.e. you don't get spark). If it is too close the raised bump will hit the pickup coil and be quickly destroyed. Hitting may only happen once the engine gets fully warmed up.
I don't know the spec's for your engine, but every spec I've seen for other engines specify 0.020" to 0.025" clearance between the pickup coil and the raised steel bump on the flywheel. If you don't have a feeler gauge, take a dollar bill and fold it in thirds. Then double it over again to get a bill that is six layers thick. That is 0.023" (close enough). Use that as a spacer to set the clearance between the pickup coil and the raised bump.
In case anyone is wondering how this works:
That raised steel bump is not a magnet. It is just a raised bump of steel. The magnet is stationary and recessed inside the pickup coil itself. It is arranged inside a shielded tube with an opening on the end such that the pickup coil can't see more than a few tens of thousands of an inch outside of the pickup coil. If you think about it, this is completely necessary to keep the pickup coil from seeing the powerful embedded magnets that generate the 12 volts battery charging circuitry.
The raised bump of steel bends the magnetic field in the pickup coil one way as the leading edge approaches, then bends it the other way as the trailing edge passes. This generates a plus/minus voltage pulse pair out of the pickup coil. The first arms the CDI, and the second fires the CDI.
Most pickup coils are not adjustable. Since you have an adjustable one, keep in mind that there is such a thing as "too close". There is a raised steel bump on the flywheel that passes underneath the pickup coil in close "fly by". If it is too far out you never get a trigger pulse to fire the CDI (i.e. you don't get spark). If it is too close the raised bump will hit the pickup coil and be quickly destroyed. Hitting may only happen once the engine gets fully warmed up.
I don't know the spec's for your engine, but every spec I've seen for other engines specify 0.020" to 0.025" clearance between the pickup coil and the raised steel bump on the flywheel. If you don't have a feeler gauge, take a dollar bill and fold it in thirds. Then double it over again to get a bill that is six layers thick. That is 0.023" (close enough). Use that as a spacer to set the clearance between the pickup coil and the raised bump.
In case anyone is wondering how this works:
That raised steel bump is not a magnet. It is just a raised bump of steel. The magnet is stationary and recessed inside the pickup coil itself. It is arranged inside a shielded tube with an opening on the end such that the pickup coil can't see more than a few tens of thousands of an inch outside of the pickup coil. If you think about it, this is completely necessary to keep the pickup coil from seeing the powerful embedded magnets that generate the 12 volts battery charging circuitry.
The raised bump of steel bends the magnetic field in the pickup coil one way as the leading edge approaches, then bends it the other way as the trailing edge passes. This generates a plus/minus voltage pulse pair out of the pickup coil. The first arms the CDI, and the second fires the CDI.
#38
12-03-2022, 11:10 AM
Is my CDI bad?
I have a TAO 110cc. I am getting no spark. Originally, the stator was damaged, which I replaced along with the pulse generator, and ignition coil. It has a five (5) pin CDI, and I measure the following;
stator output when cranking: ~ 37 volts
pulse generator when cranking: ~ .7 volts
i disconnect the output wire (yellow/black) from the ignition coil and measuring the CDI output, I measure ~ 5.7 volts. I have tried three (3) CDI’s with the same measurement. I “ohmed” each of my CDI with a ohmmeter in reference to the ground pin and I do not measure a short between the pins. My question is: is the output voltage of the CDI to the ignition coil supposed to be about 5 volts?
stator output when cranking: ~ 37 volts
pulse generator when cranking: ~ .7 volts
i disconnect the output wire (yellow/black) from the ignition coil and measuring the CDI output, I measure ~ 5.7 volts. I have tried three (3) CDI’s with the same measurement. I “ohmed” each of my CDI with a ohmmeter in reference to the ground pin and I do not measure a short between the pins. My question is: is the output voltage of the CDI to the ignition coil supposed to be about 5 volts?
#39
12-04-2022, 03:09 AM
No, with CDI systems it may be as high as 100v. However knowing what is an acceptable voltage is tricky, 0.7v on the pulse generator seems low, but without another identical quad to test, you don't know what it should be. The Lynn Edwards sticky "help diagnose stator" at the top of this section may help, as I suspect the tests were done on a Tao Tao or similar "Honda Cub clone" engine.
#40
12-12-2022, 11:30 AM
Hi,
I was able to connect a scope to the cdi connector. There is a voltage about 37 volts from the stator output. I also measure the pulse generator output when I crank. I disconnected the YELLOW/BLACK wire which is the cdi output that goes to the ignition coil. On the scope, I see the output pulses from the cdi, about 20 volts. When I reconnect the yellow/black wire to the ignition coil, I lose the output signal from the cdi. This is a new ignition coil, and a new cdi. The resistance from the cdi connector (cdi unplugged) to the ignition coil is 1.7 ohms. Did I damage the cdi when prior to this test I reversed the wires at the ignition coil and cranked the ignition.
so, I verify the stator output, the pulse generator output, I have a new stator, new cdi, ignition coil but no output when I connect the yellow/black wire to the ignition coil. I’m at a lost right now. Can you provide help with what I may be overlooking.
‘thank you.
hary
I was able to connect a scope to the cdi connector. There is a voltage about 37 volts from the stator output. I also measure the pulse generator output when I crank. I disconnected the YELLOW/BLACK wire which is the cdi output that goes to the ignition coil. On the scope, I see the output pulses from the cdi, about 20 volts. When I reconnect the yellow/black wire to the ignition coil, I lose the output signal from the cdi. This is a new ignition coil, and a new cdi. The resistance from the cdi connector (cdi unplugged) to the ignition coil is 1.7 ohms. Did I damage the cdi when prior to this test I reversed the wires at the ignition coil and cranked the ignition.
so, I verify the stator output, the pulse generator output, I have a new stator, new cdi, ignition coil but no output when I connect the yellow/black wire to the ignition coil. I’m at a lost right now. Can you provide help with what I may be overlooking.
‘thank you.
hary