New Coil No spark

[Rivets]

Smarter than me, as I couldn’t even find a PA420A engine. Most be getting old.

 

[bertsmobile1]

Could not find it through the Kawasaki portal but was there in the JD portal.
Guess it is a unique number for JD so one can not use generic Kawasaki parts.
Now experienced enough with the big K to know if it is just a different name or not.

 

[Rivets]

Can’t get into JD portal from home, so that makes sense. Wish the OP would under stand he needs to help us by posting all numbers, decal numbers from the frame would have allowed me to get in the back door. Oh well, have a good Easter.

 

[bertsmobile1]

Kawasaki comes through one of my wholesalers web site.
Downs side of that is after 1/2 hour of no activity the wholesalers site tosses me out so I have to start from scratch again.
The JD portal is access in a similar mannar except it is unintentional and will eventually get closed out but while the sun is shining I will make hay .

 

[ReallyneedHelp]

Ok,
I did some digging and the PA420A engine was fitted to the JD F510 mower
The PA420A engine is fitted with an external trigger module , called an Igniter for some stupid reason known only to Kawasaki

Now magneto ignitions theory 101
When a magnet approaches a coil it will generate a voltage in that coil.
then as the magnet departs in will generate another voltage with the opposite polarity
Depending upon which way the maget is fitted or the coil is would will determine if you get a posative pules first followed by a neagative one or visa versa
To make a spark you have to suddenly collapse a flux field within a coil by grounding it. at its highest voltage ( remember it is AC so it can be + or - volts ).
To prevent any spark being generated by the coil it gets grounded all the time.
Decades ago this was done with a set of points that grounded the primary winding plus a switch running in parallel with the points .
Points do not care weather they are working on the + pulse or the - pulse .
In 1966 a clever Hungarian immigrant living in OZ worked out he could replace the troublesome points with a solid state trigger using the rising voltage in the coil to cause the coil to ground at the right time.
This was called the Hall effect trigger and was marketed by them as the Atom ignition module. A stand alone solid state device that you simply replaced the points with.
However this device IS POLARITY SENSITIVE .
After patient had expired so they would not have to pay the 50¢ royalty every engine maker that had not already switched to solid state ignition did so by fitting their own module.
Then the engine makers realized that they could incorperate this trigger chip within the coil and charge a small fortune for them.

Now your engine originally had a stand alone trigger ( igniter ) module with a plain coil.
So to work it has to be used with a plain coil not a latter one with a module included .
I fear that your problem is you have non compatiable magneto parts or a dead igniter module that you are yet to locate

So follow the kill wire it should connect to the igniter module and it has to be there some where unless the coil has been upgraded to one with an inbuilt module.

You might find this Video form Taryl Fixes all helpful.
Note to work you have to install the coil upside down to get to polarity of the generated voltage correct for the module to work
Kawasaki igniter coil ignition modification.

Well I got the new ignition igniter installed and I still don’t have spark.tried it with the new coil and even with the old one. Checked wiring over that it attaches to and do not see any breaks. There is this little plastic cylinder on the wire and I can’t tell why it is there or what is inside it. I will try to post a pic of it.

 

[ReallyneedHelp]

Well I got the new ignition igniter installed and I still don’t have spark.tried it with the new coil and even with the old one. Checked wiring over that it attaches to and do not see any breaks. There is this little plastic cylinder on the wire and I can’t tell why it is there or what is inside it. I will try to post a pic of it.

I put a wire to jump around the plastic thing and that did not help. Here is a kind of curious thing. I can pull up on the pto button and still get the mower to crank. I don’t remember being able to do this before. I thought that having the pto engaged acted like a kill switch in the past. I could really use some help from you experts to solve this for me. Hate to give up on this mower after all these years.

 

[ReallyneedHelp]

I put a wire to jump around the plastic thing and that did not help. Here is a kind of curious thing. I can pull up on the pto button and still get the mower to crank. I don’t remember being able to do this before. I thought that having the pto engaged acted like a kill switch in the past. I could really use some help from you experts to solve this for me. Hate to give up on this mower after all these years.

The other thing I changed on this mower is a new ignition switch. I have to use a extra toggle switch with my ignition switch to connect two of the poles together so that it will crank. I have been using it this way for ten years or so. Just makes me wonder if that caused something else to go wrong. I have looked at the four fuses on the mower and they look fine. But if it’s cranking fast would any of this matter? Doesn’t this boil down to a coil and a spark plug along with the ignition igniter? Should I try ordering another OEM coil , maybe a John Deere one ?

 

[bertsmobile1]

Yes if you can crank with the PTO engaged the switch or the wiring is a problem.
The PTO also has a magneto kill wire as part of it so it may have been the PTO switch all along.
Advising how to test this over the web will be a problem as there are several ways it could be wired.
Usually the kill wire wold go to the ignition module but some mowers have it spliced into the loom and others have 2 terminals on the module itself.

 

[ReallyneedHelp]

Yes if you can crank with the PTO engaged the switch or the wiring is a problem.
The PTO also has a magneto kill wire as part of it so it may have been the PTO switch all along.
Advising how to test this over the web will be a problem as there are several ways it could be wired.
Usually the kill wire wold go to the ignition module but some mowers have it spliced into the loom and others have 2 terminals on the module itself.

. Thanks for your response.
Should I try disconnecting the pro switch and cranking to see if I have a spark.

 

[bertsmobile1]

You can not do that because the PTO switch is part of the cranking circuit as well so you can not crank the engine with the blades engaged.
That is why there are 5 to 7 wires on the plug.
JD generally uses a relay to fire the starting solenoid
One st of safety switches is connected to the negative trigger and the others are connected to the posititive trigger so both have to be in the right place before the engine will crank.