Ok so I have an alphasports LG-150 with a no spark problem... I bought a manual with wiring diagrams (Diagrams, not schematics as i would have liked) and ive already checked my ignition coil, solenoid, starter switch, kill switch, reverse indicator, brake sensor, battery and fuse, so ive narrowed it down to the magneto/stator... The manual shows that i have four wires coming from what it calls the generator ( im assuming magneto/stator because the colors match up). BUT, i have five wires coming from the actual coil; yellow, green, and white all go to the voltage rectifier/regulator; a blue/yellow wire goes right to the CDI.. But i have a black/red wire just hanging out.. Im pretty sure thats important, but my diagram doesnt even have a color code for a black with red stripe wire on it at all. So where does this mystery wire go, and what does it do? or is this the wrong magneto coil thing in my atv?

 

Your starter solenoid, start button, reverse indicator, brake sensor, and battery have nothing to do with generating spark as long you can get the engine to turn with the starter motor. Am I correct that you are using the starter motor to turn the engine?

How exactly did you test the kill switch? How did you test the ignition coil?

The description words Magneto/Stator/Generator/Alternator are often interchanged (incorrectly). So yes, your "generator" is the stator.

The black red wire from the stator is the AC power wire that goes to the CDI in an AC powered ignition system. On quads with 12 volt DC powered ignition systems most do not have this wire. Yet there are transition quads that still have the AC ignition power coil in the stator even though the CDI uses DC power. I suspect your quad ignition is DC powered. If this is true then this wire would just dangle unconnected.

For your no spark problem I would first find out for sure if your CDI is DC powered or AC powered. You cannot tell by looking at the CDI - they often look the same. Check out this link for some good info on how to measure this:

http://forums.atvconnection.com/chin...se-stator.html

Then use a meter to measure all the inputs to the CDI with the CDI disconnected:
1) Power (power - be it AC or DC)
2) Trigger signal
3) Kill switch(es)
4) Ground

After that measure the CDI output as best as we can using a meter.

I can guide though this process, but where to start? Please explain the measurements you've done so far eliminating the kill switch(es), ignition coil, and interconnect wiring. Or we can start at the beginning if that is easier .

 

Thank you for the quick reply, yes i am usuing the starter motor to turn the engine.. So I checked the kill switch with my meter and its wires coming from the switch, making sure when it should and shouldnt be an open or closed circut.. I tested the ignition coil like it told me in the manual, to read its resistance across the two spade connectors, which was .3ohms, then from the green lead to the end of the plug wire which was 3 ohms, so according to the book, its fine. The CDI is D.C. because the manual wants a peak reading in D.C. of 130-230 V going to the ignition coil but i havent done any tests on the CDI's output nor imput yet because i was focused on my "generator"'s loose wire. But that black/red wire reads A.C. so it would be best to stub and secure that wire?

 

Excellent.

OK, though it is better to check kill switches from the CDI wiring harness plug (with the CDI disconnected). That way you are checking the switch and all associated wiring as well.

Ditto for checking the ignition coil primary coil. One of the spade lugs on the coil goes to the CDI, the other goes to ground. By measuring the coil from the CDI plug your also checking the wiring at the same time.

You can only partially check and ignition coil with a meter. A shorted turn inside will keep the coil form working at all even though the reistances are in spec. Also high voltage flashover to ground cannot be detected. So what we do is measure everything in the ignition system as best we can, and if something simple doesn't pop out make the best educated guess that we can.

The output of the CDI is always AC, not DC, irrespective of what your manual says. The CDI output drives the ignition coil which is essentially a transformer. Transformers only work with AC voltage. If there was any DC component it would be shorted out by 0.3 ohms resistance of the primary.

Whether a CDI is DC or AC specifies what powers it. An AC CDI runs off a moderately high voltage (80-300 volts or so) AC winding inside the stator. A DC powered CDI runs off 12 volts DC and high has an internal convertor supply to convert that up to the couple hundred volts needed to run the rest of the CDI.

So you still need to determine if your CDI is AC or DC. As I recall from your post a couple months back you got this quad in pieces with the CDI coming with it loose. Am I remembering correctly? What I'm wondering is if this quad is someones basket case where they put a new DC CDI wiring harness on an AC CDI quad.

If your quad is wired up for a DC CDI then you can just tape up that wire and ignore it.

Below is a procedure for determining whether you CDI is AC powered or DC powered. It is block copied from another post so some of what is in there is redundant. Step 2 is guaranteed to fail since your AC power from the stator is disconnected. If you don't have a DC powered CDI then we may need to hook this up. If you do have a DC powered CDI then look at the next block for trouble shooting the no spark problem.

 

Your right, this was someones basket case, i previously had a thread about the bare wires for a CDI, that I found out was incorrect and those were for the main switch. The guy I bought this from told me those wires were for another CDI (me being a ATV novice, i assumed incorrectly), well i got those wires taken care of.. But he said he replaced the cdi and also the magneto, but i think he changed the cdi from either an A/C to a DC or vice versa, Because i have two boxes, a larger one that does nothing went connected, and a smaller one that will turn over my starter. In your last post it says that DC cdi's tend to be bigger, and the larger CDI doesnt work when i attempt to turn it over, so does that mean i have an AC one, or a faulty DC one?

 

I'm not understanding this... What does "a smaller one that will turn over my starter" mean? A CDI has nothing to do with starter motors, which is leaving me puzzled...

I don't know what kind of CDI you have. You really cannot tell for sure by looking.

Hmmm... I think you are going about this all wrong. I really think you should be measuring your wiring harness at the CDI connector (CDI unplugged) to see whether your wiring harness is powering the CDI with DC. Then check the trigger voltage, kill switch connections, etc - all from the CDI connector. The procedures are in the last post. If you find trouble here it doesn't matter if you have a truck load full of CDI's - it isn't going to work. So in my humble opinion it is premature to focus in on CDI module itself (or the stator red/blk wire, or any other component yet). First you want to gather overall data for the whole ignition system, so that you're seeing the big picture. Then we can narrow in on suspicious areas within the ignition system .

 

What i meant by that was, I was given two CDI's of different sizes, the larger one when connected and the ignition button pressed, will not turn over or crank my engine. But the smaller one that is connected shown in the picture, will crank/ turn over the engine. In your post it mentioned that D.C CDI's are larger than their AC counterpart.

But either way, i attempted those tests described in your post.

I measured 12VDC

I measured infinite ohms

I did NOT measure any resistance..

I dont know how I got this, but it measured like 18VAC?

I got low values like 4 and 5 VAC

So would it be wrong of me to say that I have a DC CDI, and that the tests show something is wrong with the ignition coil? Well thats assuming the test results are accurate with my meter.

 

My comments embedded in blue:

 

No, if i dont have a CDI plugged in, i cannot turn the starter motor.


It reads the same when the meters hookups are just hanging there. So thats infinite resistance?

 

This was not an answer I expected...

I'm really puzzled. This should not happen. Let me think about this some and I will come back after dinner...

Quote:

Originally Posted by sktbrd2

It reads the same when the meters hookups are just hanging there. So thats infinite resistance?

Yes, that is infinite resistance.