Ask the Editors: 650 Prairie Gone out to Pasture?
I reset the valves, cranks real good but wont start. Took the plug off by the flywheel and the timing checks out. Could the CDI box be bad? napoleon11
You have literally checked everything we would recommend checking in answering such a question- if you have fuel, spark and air, you should have ignition. Ordinarily a failed CDI box can be recognized right away because the machine refuses to make spark at all, or it could make a weak (yellow) or intermittent spark but these conditions are rare. Ordinarily a spent CDI box simply stops working altogether. Considering you say it makes real good spark, it’s an unlikely culprit.
About the only areas left to check would be the grounds and perhaps the ignition coil. The fact that this problem didn’t begin until you left the ignition on suggests that despite making spark, the issue is electrical.
Another test we would immediately perform would be to try and start the machine using the manual recoil starter rather than the electric.
While you say the engine is getting fuel, have you attempted to inject some starting fluid directly? If so does the machine fire up even temporarily?
You’ve certainly gone ahead and checked all of the more complicated mechanical processes, now back up and experiment with some of the simpler ones and let us know what happens.
