My son's quad all of a sudden died mid-ride and has never started again. I have changed the CDI, Stator,Coil and recitfier bascially anything I could think of. I have been doing some reading on here and trying my best to check any problems with the kill switch. Does anyone have any suggestions- I have a really disappointed 5 year old.
Thanks

 

Do you have spark?

Take out the spark plug, wire it back up and hold the plug threads against the engine block. Set the kill switches to the "run" position. Turn on the ignition switch. Crank the starter motor and look for spark across the plug gap? Do you see spark?

If yes, put your thumb over the spark plug hole. Push hard. Crank the engine. Are you abale to hold the pressure in, or does it force your thumb off the hole with a "pop"?

Dribble in 1/2 teaspoon of gas into the spark plug hole. Quickly reinstall the plug (start the threads with your fingers before using a wrench) and try to start the quad. Any signs of ignition?

 

No Spark- I am stumped

 

have you checked the spark plug's condition? cracked ceramic? have you tried a new plug? is the tether kill switch, if applicable on your quad, in the proper position? have you measured the voltage coming out of the key/ignition switch? look up under the plastic and give the ignition switch (key switch) a good once over. check the wiring there for any loose connections or cut/damaged wires. hmmmm. does the brake light work? that could be part of the interlock/safety system. hmmm....check back with us soon.

 

If Jaster94's suggestions don't uncover any problems then we may need to dig in further...

Does your CDI have 4 pins or 5 pins? A four pin CDI is powered by 12 volts DC from the battery. A five pin CDI is powered off moderately high voltage AC power from the stator. We will need to measure/verify the CDI power with a meter once we know what we need to look for - hence the 4 pin/5 pin question.

The CDI also need a trigger pulse to tell it when to fire. This can also be measured with a meter.

The kill switch circuitry needs to be tested. If a kill switch is stuck on you will have no spark.

We can sort-of test the output of the CDI to the ignition coil primary with a meter.

But before all of this we need to know what kind of CDI (4 pin or 5 pin) so we can use the right procedures - which differ between the two CDIs.

 

Thanks for the help. I was doing a once over again this morning and realized that the new coil they sent me was wired backwards- swapped the wire and had spark! Everything seems to good to go now!
Thanks again

 

Spoke to soon- I had spark so I greased all the connections and tied some wires up with a zip tie- Now NO SPARK. So I am thinking it is a bad connection....any thoughts?????

 

hmmm..check wire by wire for continuity. you may find the break. or look where you may have "stressed" the wire. either by the zip tie or where the final connections are located.. Lynn would know best.

 

So I rechecked the wires and found that the ignition timing wire was loose in the CDI. It wouldn't connect when pushed in fully so I backed it out a bit and it worked- I had spark. In the end I had to pull it out- squish the plug a bit and it fits in the pin better- hopefully it continues to work.
Thanks for all the help

 

Good call Jaster94!