Kawasaki FD731V AS09 ignition/coils testing question

Hardluck

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How do I test the ignitions / coils on the Kawasaki FD731V AS09 V twin.
Do they need to be removed from the engine to be tested?
Is hard to sit on the seat to turn over the engine and check for spark on the plugs at the same time.

I know I am old and a D...B a.. !
Thank you
 

txmowman

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The coils are best tested for spark while on the engine. You can use a running (lightbulb) spark tester easily to see if the coils are doing anything. A gap-type tester (pictured) is best for loading the coil. The SE line is for "small engine" or about 1/4" gap. Don't hook the ground wire to the spark plug, instead hook it to a good ground point such as a rocker cover bolt.

Also, disconnect the ground wire to each coil to see if the spark returns.
 

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slomo

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A gap-type tester (pictured) is best for loading the coil.
Yup, all electrical circuits require full amperage load testing. You can gap an old plug to 1/4" as well. Ground the plug body and spin the engine.
 

Hardluck

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Thanks for the answers.
Yee I clean the engine block and fins often. This engine is water cooled. FYI.
 

Hardluck

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Are coils failures a common failure item on these engines . It has less than 50 hours on it even though it is 15 years old. it sat in a garage unused for about 10 years. It ran fine for the next 2 years then it would stay running.
Should I just replace the coils and be done with it?
 

txmowman

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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.
 

Tiger Small Engine

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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.
Ignition coils don’t commonly fail in general.
 

Hardluck

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Kawasaki FD731v AS09.
I have tried to look online, YouTube, etc. as well as the Kawasaki site but can't find any info om it.

Thank you. These new testers are really much better than the old inline tester that only showed spark, you couldn't set the gap.
The coils tested fine so that is one thing that was good.
Now I am trying to find the carburetor adjustment specifications for the carb, I have replaced the carb but am basically having the same issues. running rough and not running at all when the engine gets hot (it still has spark when hot)
I screwed up and tried to adjust the carb and have already removed the black caps, I now have the screws adjusted out about 6 turns which I know is way to far / many.
I have to remove the air filter and brackets to get to the adjustment screws and I don't know how much difference it will be in the adjustments when I replace the filter elements. I haven't been able to adjust it is hot as I can't keep the engine running long enough.
Right now It starts with full choke and after a little bit it runs at about half choke but never with on choke. the longer it running the less power it has and i can't keep it running even adding and removing choke.
It does seem to me like it needs gas. Also I have replace the fuel, fuel lines, filters both air and fuel as well as the fuel pump.
Thank you greatly, I do feel like maybe there is hope for me on this! If all else fails I'll start at 1 1/2 turns out for the screws. I am curious of both are set the or they set differently.
 

RevB

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Are coils failures a common failure item on these engines . It has less than 50 hours on it even though it is 15 years old. it sat in a garage unused for about 10 years. It ran fine for the next 2 years then it would stay running.
Should I just replace the coils and be done with it?
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.

1000012609.jpg
 

StarTech

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Kawasaki FD731v AS09.
I have tried to look online, YouTube, etc. as well as the Kawasaki site but can't find any info om it.
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)

1743268134641.png
 
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