D1E41QMB No Spark Help
 

OK here is the story

I took some measurements. I have 3 wires from the stator 1 goes to ground. No resistance to the case. 1 goes to coil. 2.4 AC Volts during crank. 1 goes to rectifier 3.6 Volts AC during crank. Coil is a single wire coil. Mounts to frame with a bolt ground wire from negative batt attaching to mounting bolt. no resistance on that wire or the coil to the case.

Image of stator and ignotion coil below
Attachment 17707
Attachment 17708

Both of those pictures show ordinary components of a standard CDI ignition system:

1) The stator picture: Moderately high voltage AC power supply for the CDI module is on the left, and the battery charge AC coil is on the right. Ordinary generic stuff which needs a CDI...

2) The coil picture is the same thing. Ordinary generic coil driven by a CDI.

Yet you say this is a non-CDI system. Why do you say that? Can we back up a bit?

What is the history of this quad? Did you just buy this? Have you ever seen it run?

I haven't searched your engine model number. Can you you give any more info on what type of quad we are talking about? 110cc? 90cc? 150cc? Four stroke? Two stroke?

I want to help you :). I'm asking a lot of questions because I need info to figure out where we stand and what to do next.

These are two standard generic CDIs: Do either of them exist anywhere on your quad? They would normally mounted high up under the gas tank or under the seat:

Attachment 17704

Attachment 17705

This is a bone stock chineese atv Brand DURABULL I rsearched the VIN and the Engine Code to get where I am at now. I have stripped everything off the atv and exposed every wire. No CDI and nothing looks to ever being messed with. the Vin at Engine code say it is a 50 CC with engine number D1E41QMB it is a 2004 model. Other post I have found show that this particular ignition coil is not a high voltage coil here is the post I found ScootDawg Scooter Forum - QM50QT-B2 No Spark it is a low voltage coil and stator.

This is very interesting...

I've got to go to work right now. Let me do some research later today and see what I can come up with. I'll respond later tonight.

I also tested the new stator assembly according to scootusa website who sells the exact replacement part. I have 2 ohm resistance between the gray and and brown and wires and 156 ohms between the black and white wire as outlined here www.ScootUSA.com Scooter Testing The Stator also if you look at the coil in the above picture there is no outside pickup along the edge of the stator as in most high voltage stators.

Here is a wiring diagram for the unit


Attachment 17695
http://s1196.photobucket.com/albums/...irediagram.jpg

I had never heard of a non-CDI ignition system, and as you probably surmised from the scootdawg forum responses there were a lot of naysayers there too. And the other consensus I found from various posts on this subject is that no one is really sure how it works.

That ignition power coil of wire in the stator will generate voltage as the flywheel rotates the magnets past it, but I don't think it will not generate any near good enough for timing of the ignition firing. I'm still looking for the trigger mechanism. All ignition systems have them - whether it is a pick up coil, cam driven switch, or solid state switch - but there must be something that produces a fast edge to trigger the spark.

I read in several places where the coil on your engine is "special", and that substituting a generic coil results in no spark. I also read that the standard coil test where you read the resistance of the primary winding reads infinite ohms (open) instead of less than 1 ohm. Obviously there is more stuff inside your ignition coil than the just the two windings. Perhaps there is a whole CDI inside. Or maybe a solid state magneto system.

But how does this "special" ignition coil get triggered? Where does this ignition coil mount on the engine? I noticed on one picture on the internet your coil has a pole piece sticking out one end of the coil (not to be confused with the mounting tab which sticks out the other end). Does this pole piece mount near any rotating machinery on the engine? Like maybe the flywheel? Try as I might I could not find any pictures of a mounted ignition coil. I wonder if the trigger pickup is built into the ignition coil as well.

Your ignition power voltages from the stator (white wire to ground) seem all wrong. But in order to measure them you need to have the ignition coil unplugged (white wire). So unplug the ignition coil and measure the AC voltage on the white wire to ground while cranking the engine. What do you measure?

The wiring diagram in the scootdawg forum link shows four wires on the stator output connector. On yours you're missing the black wire (which is ground). Since the stator is already grounded to the engine this black wire may be redundant. But the gray and brown wires are shown as both being wired to the voltage regulator in the scootdawg link, yet your wiring shows one them tied to ground at the battery negative post. Something is not right here. It may well be that the scootdawg link is wrong, but maybe not.

Try this: Disconnect the stator connector. Use an ohmmeter to measure the resistance of the gray wire of the stator pigtail to ground (measure the stator - not the wiring harness). Do the same for the brown wire. Do you measure continuity to ground on both these wire? What are their resistances?

Leaving the stator disconnected measure the AC voltage on the gray wire to ground while cranking the engine. Do the same measurement for the brown wire. What do you measure on each wire? What I'm trying to do is figure out why your battery charge winding is also measuring way low.

As far the ignition problem goes, if we can see that the stator is putting out voltage while cranking (more than a couple of volts) then the only thing left is the special ignition coil. Maybe you have two bad ones. But lets make sure the stator is working first.

Measurement results
 

Brown and gray wire 9.2m to ground
Brown 2.9 VAC during crank wire goes to rectifier
Gray 4.0 VAC During Crank wire goes to nothing
white 20 VAC during crank wire goes to ignition coil.
HOWEVER
when I plug the ignition coil back into the white wire and remeasure it drops to 3.6 VAC

The other 2 remain the same.

when you lost the 20 VAC by hooking the coil back up, was the coil connected to the sparkplug? just an off the wall guess, its rare, but you could have a shorted plug,so the voltage gets shunted mostly to ground instead of the electrode.It would have to be bad internally for the voltage to short out before getting to the electrode, but I have seen bad plugs in cars, even one bad out of the box. Have you tried a new plug, just to eliminate that part? seems like you have pretty much tested everything else.

Tried it today both ways no change.