[ylwhrse]

I have a John deere 425 I just bought used that is ~ 9-10 years old. 367 hours on tractor. Mice had chewed up the temp sensor wire and 2 wires on the time delay module. I repaired the temp sensor wire and replaced the time delay module, I have no spark. I checked the coils and I have power to the coils, however when checking the negative side of coil it also has power. I unplugged the black/yellow wire on #1 coil & white wire on the #2 coil and tested the negative coil terminal on each coil and have power at the terminal. I also tested the black/yellow wire and white wire for continuity to ground but get no continuity (not sure if there should be or not but according to wiring schematic those wires are negative for coils) I am stuck and not sure where to go from here? Dose anyone know if there is a test for the coils ? And also a test for the igniter / module ? Please help if anyone can point me in the right direction to go. Thanks Tim

[crigby]

Hi,
Your 425 is a Kawasaki that uses a battery-energized system. Cannot look up the harness, sorry. My opinion is to replace the wiring haness. Yes, I have done this on many an occasion. Not for the faint of heart as it is 4 1/2 - 5 hours to do it.
Peace,
Clarke

[ylwhrse]

Yes thanks Clarke, but the chewed up wires were very small damage mostly only the time delay module wires and the temp sender wire, all of which I have repaired. I found a schematic of the harness from Kawasaki and even performed the ohm test on the coils ( which all tested in the normal range) What I think is odd though is When the key is off there is power to the positive side of the coils at all times ( I thought this was odd) also upon checking the negative side of coils It also has the same voltage. When I test the negative wire for the coils for continuity to ground there is none ( not sure if that is normal either) So I wondered if the ignition module or igniter as they call it could be shorted internally ? ( maybe when the mice chewed wires it fried something ) I don't know if that even is a possibility or not. But the fact the negative side of the coils is getting voltage is puzzling me. What is your thoughts on that? The harness itself after inspection looks good everywhere else. Like I said the main damage was to the wires of the time delay module and the 1 temp sender wire and I almost forgot they chewed a wire that goes to a sensor on the front of carb ( but it was just chewed in half- I reconnected it and soldered all connections then heat shrinking them then electrical taping over that) Thanks Tim

[crigby]

Hi,
Not sure if this is the manual you got, but here is a link:
http://www.mymowerparts.com/pdf/Kawa...AIR-MANUAL.pdf
This is ont of the few engines still using a battery energized system. It uses a pair of pulser coils to detect the position of the flywheel and the igniter(which is also the spark advance) then energizes the ignition coils. I do not remember them having battery voltage with the key off. Understand that the key switch has an integral module attached to it that is part of the system and could be causing that. Not the kind of machine you want to play parts swapper with. Easiest way I know to test it is by plugging in a know working module - you do not have to connect anything but the two plugs to the board on the right and under the dash. All this can be done by those plugs and not removing anything except the known good module from the working machine. I used to keep one of those around that had a different circuit blown for a test unit.
You may notice the tha spark plug caps have 5K cast into them(not all did) and that means they should be a 5 kilohms nominally if so stamped
Do give the manual time to download as it is large, 166 pages.
Peace,
Clarke