1998 YZ400F NO SPARK?!?



3 replies to this topic
  • Craig1776

Posted November 21, 2015 - 08:51 AM

#1

I recently bought a 98 yz400f for a $700. The bike had no spark but for $700 I thought I could easily find the problem and already be riding the thing. I started with the kill switch, that wasn't the problem. New spark plug...nope. I tested the stator and the numbers seemed to match what the manual said. So I bought a new CDI and a new Coil, put them on and...nothing. Is there anything I'm missing? Any help would be greatly appreciated! Thanks!

  • Caleb99olsen

Posted November 21, 2015 - 12:11 PM

#2

Check for any broken wires for the stator or anything check them all. And also check for a corroded ground? That's just a guess but worth to check

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  • grayracer513

Posted November 21, 2015 - 12:21 PM

#3

It won't start, so you think it has no spark, or it actually has none by test?  Most of the time, problems with making an old 400 or 426 run for the first time in a while are in the carb.

 

But if you really have no spark, ring out the harness and check the grounds as suggested, then back probe the connected harness at the voltage inputs to the CDI.  Use an analog meter or a DVOM with an analog scale in the display and test for AC voltage while you crank.  You should get something like 5 volts on one and 9-10 or so on the other. 



  • Craig1776

Posted November 21, 2015 - 03:44 PM

#4

I've tested for spark and it was non existent, but I will try what you just said, thank you!





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