After swapping coil,pulser coils,spark plugs,and connections no fire on left cylinder

[Rob50056]

My 425 was running great then suddenly no fire to left cylinder.
I pulled plug wire off no spark so I switched coils,then plugs,then pulser coils and still only right side fires at plug.
I cleaned up connections and checked each side of connector for continuity and all connections are good.
Is there anything else I can test?
The only thing left is the black box which I have no idea what it's called other than ignition module or brain of some type.
I tested the four outlets from one connection from black box that go to pulser coils and they all read resistance given in Manuel.
Any suggestions on what to check next or double check?
I even pulled off valve cover to make sure valves were open and closing and they were fine.
I may try starting it up in dark to see if there is any spark jumping but I don't hear any spark jumping.

 

[CalG]

Kawasaki..

small engine 101, throw parts at it, cheapest to most expensive, until the trouble goes away.........

Sad isn't it?

 

[Rob50056]

Kawasaki..

small engine 101, throw parts at it, cheapest to most expensive, until the trouble goes away.........

Sad isn't it?

Have I ruled out every part that can cause symptoms?
The coils have to be good because when switching them the right side still got spark.Likewise with spark plugs and pulser coils.If right side didn't fire after switching each part one at a time then bad part should have shown itself if one if the above.
Is there any other parts that can keep a cylinder from firing at plug than coil,pulser coil and spark plug?

 

[crazyal]

I do believe that black box is the igniter. Chances are it's your problem but the bigger question is why. The ignitor isn't cheap so I would try my best to make sure it's not the problem. You can do a couple tests. Do you have a multimeter? If so you can check to see if the coil is getting 12v when the key is on. Then check to see if the wire going from the coil to the ignitor has conductivity. Finally, this might be a little harder but you could reverse the two wires coming from the coils to the ignitor (think all this will do is confirm that everything from the ignitor to the plugs is fine which the other two test should do). Finally take a real good look at the ignitor's wires for any damage and check every ground. After that I think you are stuck replacing it. The problem is that if a wire shorted out and caused the damage and you don't fix the root cause you will most likely damage the new ignitor. Since you just did major work to the engine it's possible that something else caused the ignitor to die.

 

[Rob50056]

I do believe that black box is the igniter. Chances are it's your problem but the bigger question is why. The ignitor isn't cheap so I would try my best to make sure it's not the problem. You can do a couple tests. Do you have a multimeter? If so you can check to see if the coil is getting 12v when the key is on. Then check to see if the wire going from the coil to the ignitor has conductivity. Finally, this might be a little harder but you could reverse the two wires coming from the coils to the ignitor (think all this will do is confirm that everything from the ignitor to the plugs is fine which the other two test should do). Finally take a real good look at the ignitor's wires for any damage and check every ground. After that I think you are stuck replacing it. The problem is that if a wire shorted out and caused the damage and you don't fix the root cause you will most likely damage the new ignitor. Since you just did major work to the engine it's possible that something else caused the ignitor to die.

When you say ignitor are you referring to black box?
Ill try switching the output from connecting plug from black box so that it feeds the coil that's not firing.That should be the fastest way to eliminate quite a few parts.

 

[Rob50056]

When you say ignitor are you referring to black box?
Ill try switching the output from connecting plug from black box so that it feeds the coil that's not firing.That should be the fastest way to eliminate quite a few parts.

If the ignition delay was acting up wouldn't that effect both cylinders?
If Im looking at schematic correctly the delay has one wire,yellow,that Y's to both ignition coils.So if the delay was bad neither side would work.

 

[Rob50056]

If the ignition delay was acting up wouldn't that effect both cylinders?
If Im looking at schematic correctly the delay has one wire,yellow,that Y's to both ignition coils.So if the delay was bad neither side would work.

I checked both wires going to both coils with key off and on.With key on position on the left side,not firing,the voltage only read 1.0 volts while the other side that fires measures 12 volts.
I traced 1.0 volt wire to black box plug and the side that was working to see if voltage was continuos or broken wire or bad connection.
The output at black box plug feeding coil was only 1.0 volts while the side that fires read 12 volts just like at coil.
The wires from black box going to pulsar coils all were grounded with key off and read 0.14 volts with key on.
I started to switch wires to both coils so cylinder not firing would get fire from components feeding side that was firing but what about timing and which wires to switch?
The wires going directly to coil from black box is simple but what about wires that are effecting the timing of firing.
Which wires need switching so the left and right side get correct timing?The pulsar coil wires?

 

[Richard001]

I checked both wires going to both coils with key off and on.With key on position on the left side,not firing,the voltage only read 1.0 volts while the other side that fires measures 12 volts.
I traced 1.0 volt wire to black box plug and the side that was working to see if voltage was continuos or broken wire or bad connection.
The output at black box plug feeding coil was only 1.0 volts while the side that fires read 12 volts just like at coil.

Rob - it sounds like you have identified the problem with the lack of proper voltage coming out of the control module.

Richard

 

[Rob50056]

I do believe that black box is the igniter. Chances are it's your problem but the bigger question is why. The ignitor isn't cheap so I would try my best to make sure it's not the problem. You can do a couple tests. Do you have a multimeter? If so you can check to see if the coil is getting 12v when the key is on. Then check to see if the wire going from the coil to the ignitor has conductivity. Finally, this might be a little harder but you could reverse the two wires coming from the coils to the ignitor (think all this will do is confirm that everything from the ignitor to the plugs is fine which the other two test should do). Finally take a real good look at the ignitor's wires for any damage and check every ground. After that I think you are stuck replacing it. The problem is that if a wire shorted out and caused the damage and you don't fix the root cause you will most likely damage the new ignitor. Since you just did major work to the engine it's possible that something else caused the ignitor to die.

How can one reverse wires the wires coming from coils but keep valve and fire timing in sync ?
Switching wires from module to coil is straight forward but won't coil pulsars wires feeding module have to be switched also?
In effect by switching the working channel module is bring used,if left side is bad?
The work I did was replacing water pump last year and cam gear this year and it's basically the same tear down,remove crankcase cover,and only battery and ground on the crankcase connections are taken loose.
So I can't see any work done causing problem to ignition.

 

[CalG]

How can one reverse wires the wires coming from coils but keep valve and fire timing in sync ?
Switching wires from module to coil is straight forward but won't coil pulsars wires feeding module have to be switched also?
In effect by switching the working channel module is bring used,if left side is bad?
The work I did was replacing water pump last year and cam gear this year and it's basically the same tear down,remove crankcase cover,and only battery and ground on the crankcase connections are taken loose.
So I can't see any work done causing problem to ignition.

Rob

You are correct, Swaping wires will screw up the ignition timing. But so what!?? With the spark plugs out of the heads so you can observe the spark, the engine could care less. There is no need to actually run the engine on the other bank.

If swapping wires moves both spark and dead to alternate sides, you have identified the problem as "the black box". Now if swapping wires leads to either good spark, or no spark on both sides, then you need to continue your efforts. AFTER you swap the wires back to original.