300ex help!!!!

[outindeltona]

working on a 300ex for a friend that has a no spark issue. has power,ground getting to the cdi box,has 5v ac while cranking going to the exciter wire at the cdi box,im assuming it has signal from the pickup coil. does anyone know what the ac voltage coming from the stator should be while cranking? only getting 5v ac on all 3 wires at the rectifier and to the exciter wire at the cdi.all the impedances are fine according to the manual,replaced the cdi coil and stator with a known good one...still no spark.

[outindeltona]

no one else has a 300ex?

[svtbolt04]

By chance, did you pull the cap off the lead and switch to an ohms test? Also, the plug wire could have backed into the insulation.

Check if the run/stop switch is bad, it would crank and no spark too.

[johndoe83]

check the on/off button?

I took my quad apart 3 times one night because the on/off was off.

[outindeltona]

yep checked everything and according to the manual all the impedances are correct.i even have bypassed the ignition and the kill switch too..still no spark or voltage to the coil except for a lil spark when you let off the start button.the cdi and stator came off a running bike.

[johndoe83]

Ill bet money somewhere down the line one of the wires for either the on/off or the coil...etc.

The wire is grounding out and making the rest act as if its turned off, it could also be a broken wire.

If new stuff from a running quad wont work either and there is a small hint of spark at one point "letting off the start button" then there is a wire ground out or not grounding out somewhere or a broken wire.

If it has to do with the start button, I would assume that while the button is pushed the ground is happening, then when you let of the button a slight spin of the flywheel afterward would allow a spark!

Cut open your wire harness and try to locate a broken wire.

[outindeltona]

already bypassed and removed the ignition switch and the kill switch. it also does the same when jumping across the starter relay.

[outindeltona]

im guessing it has something to do with the 5v ac coming from the stator and on the exciter wire at the cdi.all my other quads have 10-15vac while cranking,i just dont have another 300/4000ex to test

[Stuntmanmike]

I agree with your last post, I would check to see if the the stator is making contact with the magnets, I have seen this happen many times.