Kawasaki FD731V AS09 ignition/coils testing question

[RevB]

As it so happens I just had to replace both coils at 480 hours. Yes they do fail and it not ucommon for them to fail . The post below explains why. The transistor managed coils are not all that robust given the hostile environment they live in ,primarily heat related.

FD731V and other Kawasaki twin cylinders

This is not a plea for help as it has been fixed, just a heads up on cause and effect. The ignition coils on these engines are different from the #1 and #2 side with different part numbers and have a pair of transistors inside the units that control primary winding charging and field collapse...

www.lawnmowerforum.com

 

[RevB]

Thank you for the replies. I looked up the link thanks, got some part numbers. I am still looking for how to adjust the carburetor? The advice was to adjust the carb if you had poor high rpm performance issues. But it doesn't what to set the screws at?

I can get it to start and run, and run pretty well until I start the mow , load the engine. It restarts well but will hardly pull itself up am incline with the pto on.
The coils have good spark but I am guess I am at the point that I will replace the coils since I have tried everything else. Except getting the carb adjusted correctly. The carb is very difficult to adjust when you are trying to run the mower / pto. My arms aren't long enough! LOL with the rear mounted engine on the Badboy mower!

Thanks again for any and all suggestions.

Precisely the behavior of my engine. Thought at first it was fuel pump related but no....ignition. Pulling cylinder 1 plug cap resulted in a very rough running engine. Pulling the #2 however engine ran smoothly. When I say smoothly that means the ignition was consistent with #1 coil but still way down on power.The rough running confirmed #2 coil was failing. Replaced both coils and runs as new. Starts and idles better, not as sensitive to throttle movements. This would lead me to believe your throttle may not need to be touched as this may all be ignition related.

 

[slomo]

May be a dumb question but do both cylinders have compression? I have seen twin engines come in on running on one cylinder. One rod was broken. But it "just needs a tuneup, it is low on power".
Do you have an inline spark tester? The one that looks like a troubleshooting current tester? Install between the ignition wire and spark plug, go attempt to mow and see iof the spark drops out.

https://www.harborfreight.com/in-line-spark-checker-63590.html?gQT=1

That is a tool for checking spark. Is it the best tool for checking spark, no.

Why - spark can fail at mid and high revs where the light bulb type will not show. Taryl on youtube has a video showing this exactly. These types below are superior spark testing tools.