How to check for proper spark at the plug

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1998yamahawarrior

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As we have had a rash of no sparks/no starts come on recently I decided to do a right up on checking for proper spark. Just pulling the plug, putting it in the boot and holding it on the block is not always a good check. Especially when you have spark, but are still not getting fire with sufficient fuel.

A proper/ hot spark should be able to jump 1", whether it be our little single cylinder or a V8. The main reason is that it takes more voltage to have a strong enough spark under compression than it does in the open air.

If you have an HEI spark tester that is the perfect gap and a good tester. For must of us though we dont have one sitting around or dont want to buy one. For those of us in the latter, one way is a screwdriver inserted in the plug boot. Making sure to keep your hand on the handle. If not you'll know how strong the spark is first hand!!! LOL Make sure to hold it approximately 1" from the engine. If its strong enough to jump the 1" gap you have strong spark and need to look elsewhere. If not you need to back track doing checks for the boot and coil.

Battery, coil, even the wire form the cdi to the coil, dont forget the ground wire that goes from neg. cable to the coil base.

Ill get a video for you guys tomorrow as I have a very good ignition system since everything is on mine is up to snuff!!
 
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you should add this or a link to my FAQ, i think it would get more views that way! nice write up 98
 
I'll probably add a link to yours alex, that way it can come up as a search separately. Or they can find it in yours, wanna completely finish it up first. Ive just seen it suggested to hold the plug against the engine to many times. That will only tell you if you are getting spark, but not strong enough spark. Ive been thru this with both warriors Ive owned with different things being the cause. Including a failing stator.
 
Good call on this! The holding to the head thing does not always work! Thanks for writing this up!
 
i have done this with the screw driver and i get spark at 1/4 inch and no further out also seems to have a inter mitten spark
 
Well if you think you have intermitent spark the 2 big things Ive seen cause that so far is the little ground wire that comes off the main negative and a failing pickup coil. Pickup coil(stator in general) needs to be ohmed. As for the ground follow it and you should run into a bullet connector, check to make sure its not broken or corroded.
 
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