Kawasaki FD731V AS09 ignition/coils testing question

Hardluck

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They can be but not for the reason most people would think. Here's my experience with mine.

Kawasaki coils use carbon track plug wires, simply a string that is carbon dust impregnated in the sheath. My engine would run rough at times and then one day one cylinder just stopped firing. Coil tested good but there was zero connectivity thru the cable. Removed the plug rubber cap and saw that they used a crimped over connector with prongs that penetrated the sheath to make contact with the string. Except when I looked closely there was no string visible at the end of the sheath. Cut it back past the crimped prong points and there was the carbon string. Now I could measure connectivity. Got a pair of these and everything started working again. These have a wood screw type thread that runs up into the sheath center core and makes much better contact than the Kaw setup. Not saying this is your problem but just something to check and a solution if it is.

View attachment 70695
Thank you
 

bentrim

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There may be an Igniter used on this engine according to the service manual. Best to check them before condeming the coils. If it is on a John Deere the also have a control box that will kill the spark. Ask me how I know that one gave me a fit.
I attempted to attach the service manual -- but too large. I attempted to copy & paste but that did not work either.
If someone can tell me how I can uplad the service manual, it is a pdf.
 

txmowman

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There may be an Igniter used on this engine according to the service manual. Best to check them before condeming the coils. If it is on a John Deere the also have a control box that will kill the spark. Ask me how I know that one gave me a fit.
I attempted to attach the service manual -- but too large. I attempted to copy & paste but that did not work either.
If someone can tell me how I can uplad the service manual, it is a pdf.
No igniter.
 

RevB

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Can a coil fail? Sure. It is common for both coils to fail, not likely. That is why I suggested removing the ground wire from both coils to see if either has spark.
Yes...there are two transistors in each coil and they can and do fail. Every revolution of the engine creates a spark. At 3300RPM that's 55 sparks a second. The high heat environment doesn't bode well for long life.
 

RevB

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That engine probably it is mounted on a JD mower. Kawasaki USA is barred from allowing you look it up.

Now here's a twist it uses two different coils (one of Each)

View attachment 70696
Just replaced both of mine at 480 hours on the originals. The result was dramatic.
 
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