No Spark

[vwtuner99]

I have a 2000 honda 300ex atv. It will not fire. Pulled the plug, no fire from plug. Disconected kill switch so that i know thats not it. Checked for voltage at the two wires at coil. No voltage. Does anyone have any ideas of what it could be? I guess it could be the cdi box but i dont know. I also cannot find out where that box gets its signal from to know when to fire. If anyone has any ideas please let me know!

[John451]

First check the battery connections for dirt. Then starter. Pull the cdi plug and make sure its free of dirt. The box gets the signal from the magneto (flywheel / alternator). There is a little sensor on it and where the wires go into the left cover there is a pickup where it reads when the thing goes by and send the signal / power to the cdi so it can regulate and boost the power sent to the spark. If the starter and lights work then its not the battery Id look at the cdi box's plug for dirt.

[vwtuner99]

Ok thanks! I'll check that out and let you know what I come up with.

[vwtuner99]

Found out what the problem was finally today!! Found that the spark plug boot was bad. I replaced the cdi box and still no spark was looking in the repair manual doing some checks and finally found that boot bad. Removed the boot and just put the wire on the plug and got fire! Man this thing ran me in circles but i finally got it! Thanks for your help!

[bwamos]

Glad you found it. On the 300 it almost always end up being something simple yet elusive.. lol.

That wire can get oxidixed at the boot. If you seperate it then cut back the wire about an inch a lot of times you can screw the boot back onto the wire and be good to go.