Someone please correct me if I'm wrong.

I have an Exel XL150ATV (150cc ATV with GY6 style motor). It doesn't start due to no spark.

I followed a DIY article found here about testing the CDI to determine if it is AC or DC powered. It's a 6 pin CDI with (if memory is correct) square plugs. Using my meter set to DC 20, I did not see any voltage readings (as in the display did not change) when I checked for DC voltage. However, if I switched to AC voltage at the 200 scale, it would register varying voltage levels while cranking the motor. This leads me to believe I have an AC powered CDI.

The readings though, were quite low. The DIY I followed said readings should be between 40 and 80 AC volts, however I was only maxing out at 21 and would stay around 18-19 with constant cranking (5-10 seconds).

This leads me to think my stator is bad and not generating enough voltage to produce spark to fire the engine. I pulled the stator off yesterday. The magnets on the flywheel and the edges of the stator were far from clean, there was a nice layer of dirt on both of them. I'm thinking of replacing the stator, however I'm finding there are AC and DC stators? Since I have an AC CDI, I should get an AC stator correct?

Finally, since I'm getting some voltage at the CDI< should I bother trying to clean the flywheel contacts, magento and stator with some carb/brake cleaner to clean everything up a bit and try again?

 

I think it's worth a shot at cleaning them.

 

Stator Tests - Page 7 - Electrical - VFR Discussion - Page 7

here is the test procedure for a ac stator.. reading it it looks like your cranking voltage is right on. it will not reach full output until motor is up to rpm.

 

Maybe it's the back to back 18 hour shifts at work moving 250 people 3 blocks...but it took me 5 times reading that to figure out what I was looking at.

I gave the wiring somewhat of a once-over again. I did notice some issue with a kill switch wire needed repair which I did but still no spark. I'm still trying to find some specs for an AC CDI specs to ohm it out but it's to the point of saying fudge it and just replace it.

 

*Trouble Shooter Guide for NO-SPARK Chinese Engines

 

Hehe do a Google search for testing ac stator. I stumbled across some testing info when I was looking for the above info for ya.

 

Stuck a new CDI in and have spark. It looks weak visually, but it worked. Idle is rough and won't hold unless I give it a little gas. Did some broadies in the yard and it idles just fine. Next mod I'm thinking is the auto-choke eliminate...

 

i would go through your wiring and look for bad connections and fix them up.

 

I've done that already. Had a few wires that were shorting out I replaced. Strange thing now though, I had it up & running yesterday with the new CDI.

Came home, wife wanted to try it. Kick it on and try to start it, battery is weak. It tried to start (it stumbled) but then died. I hooked up my charger to it and gave it hell again. It turned over but just wouldn't catch. I pulled the coil off the plug and ground tested it to the motor block and I wasn't getting spark again. Either there's something else going on that's frying the CDI, or the CDI I got was a bum.

 

i had the same issue on a import.. it turned out that a few wires on the back of the key switch were barley holding on. Maby 1 strand of wire. was hard to find did not find it until i had bumped the wire and got spark again and then it was gone.. I actually only pulled the switch out so i could get the wiring out closer to work on and noticed it.. Easy fix just soldered it back on. Just shows that it can be a hard one to fine if its a bad wire.. get the wife to wiggle wires while u try to start.. Also had a issue on another one where the little brass insert on the spark plug boot had worked loose and was making intermittent contact. it actually fell out on the ground.. new boot all was good again