Diagnosing No Spark Problem - '97 CR-80

[Smit-Dog]

I'm looking for some advice on how to best troubleshoot and diagnose a no-spark condition on a '97 Honda CR-80.

Holding new plug (connected to ignition wire) against outside of cylinder head and cranking = no spark.

I have an electrical probe-type tester, but am not sure how to use it, and where to use it on the electrical system.

Looking for how to use the electrical tester to pinpoint source (plug wire, kill switch, coil, etc), and where to start.

Thanks!

 

[Smit-Dog]

Hello Smit-Dog,

tyler_bishop has just replied to a thread you have subscribed to entitled - Diagnosing No Spark Problem - '97 CR-80 - in the Pit Bikes & Mini's forum of Dirt Rider . Net Forums.

This thread is located at:
http://www.dirtrider.net/forums3/showthread.php?t=155829&goto=newpost

Here is the message that has just been posted:
***************
Take off the left cover where the chains at and the flywheel is.. Maybe your (gizmo?) that the point passes is busted or something bizzar...

Sorry don't know much about ignition problems.
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Noticed that the DRN site may have been down for a period of time.... If so, were some posts lost? I received the above e-mail notification, but the post is missing on the site.

:think:

Either way, I did some very uneducated troubleshooting with an electrical connectivity tester (had no idea really what I was doing), and it appears that the 2 wires going into the case have connectivity. I get zero (apparent) connectivity testing the coil or CDI, and the spark plug cap shows very little connectivity.

OEM $ for a new CDI, coil, and spark plug cap is something like $250 ( :yikes: ), and I have already sunk WAY more money into this POS than it's worth. Found a working but used ignition system on that auction site for $90, so am thinking about getting it in hopes that it fixes the no spark condition. Sound reasonable? The dealer wants $90 just to diagnose the problem.

Thoughts? Advice?

Thanks...

 

[Clipity]

Check the ground on the coil and cdi were they mount to the frame make sure they are clean. Something else unplug the kill switch.

 

[junkjeeps]

Have you tried checking spark without the plug in the equation? Or another plug? Just to verify you have a good plug. I've seen brand new plugs not be good. Also remove the boot from the coil wire and see if it sparks to the head. Check resistance on the plug boot. Should be about 5K ohms. Maybe grasping at straws, but will help you narrow your search.

 

[Smit-Dog]

Thanks for the advice guys....

I did try a brand new spark plug, and tried for spark without the plug cap in the mix. I also disconnected the kill switch.

I will sand down the ground contacts to see if that helps. I don't know though.... It was like a light switch... ran great one weekend, completely dead 2 weeks later, e.g., not an intermittent problem.

I am going to try getting access to another CR-80 that is available for parts, and start swapping electrical components to see if it fixes the problem.