View Full Version : no spark


lister
05-02-2004, 03:50 PM
i have a john deere mini tractor with a kawisaki motor and an odd problem. there is no spark but after replacing the coil it still does not work.
i measured the resistence across the coil and it shows around 20k on both as i would expect, (new and old ones) and moving a magnet near it makes a small voltage.
i put it back on and put an old voltmeter (i was afraid i would destroy it) on it and cranked the motor and it does show a small voltage but not near enough to make a spark or deflect the needle very far or fast.(5 volts?)
i disconnected the kill wire allready and did it with it connected, and am an electronics tech so i know the theory, and this should be working, but it just wont put out.
do the magnets go bad, is there a capaciter in the circuit or is there something i missed?

dgraham225
05-04-2004, 12:57 AM
have you tried cleaning the magnet face? take some sandpaper (any grit that will take the rust off) and sand it smooth. if thats not the problem, what is coil gap set at?

bugman
08-12-2004, 09:05 PM
try a new spark plug and use a dollar bill to set the gap.when the bill moves freely when the coil is real close. to check take th sparkplug or plugs hook em back up and crank the engine to see if there is spark if not then there is something else wrong

Fourd
07-10-2005, 01:17 AM
If you are an electronic tech, then you now rust does not impeed electonic field -- that is an old vices tale. I believe resistance should be 2,500-5000 oms ... so 20K seems way to high unless you read the wrong scale on the meter??? Now this can drive one mad when it happens, but there is such a thing as a bad new part, still I would double check for ground faults... but not familiar with you engine...

scrench
07-10-2005, 02:10 AM
im going to go out on a limb here but im pretty sure that engine is going to have a small box up arround the shroud that might be causing the problem , i have replaced it with a stihl trigger unit b-4 "rust does not impeed electonic field" old wives tale well said is it an 18 hp ? twin single ?

bugman
07-10-2005, 02:15 AM
you do know the thread was made back in....05-02-2004

fords-n-mowers
07-10-2005, 02:50 AM
you do know the thread was made back in....05-02-2004
LOL!! hope its fixed by now!

bbnissan
07-10-2005, 02:24 PM
Well, since everyone else is beating a dead horse I guess I will too. The problem with the Kawasaki has nothing to do with the coil. It's the small ignition module mounted on the right side of the engine (if you are sitting on the tractor). Trust me...been there, done that, wasted half a day trying to fix it.