K181 8hp with points and condenser, no spark

[arch252]

The confusion is likely because of my improper use of terms. I've always referred to the magneto as a coil. I didn't mean a true coil, but that's obviously how it sounded.

 

[Rivets]

No, the confusion is on my part, I didn't look carefully at your pics. I didn't notice the two charging coils mounted on your magneto. My fault, sorry. Because I am not there I'm having a very difficult time seeing and understanding the wiring. If it was in front of me it would be a no brainer, but my meter won't read through the Internet. Bert, IL, do either of you have time to post on this one. I think I know how it should be wired, but don't know how to explain it, so the OP will understand. Stick around, together we'll solve this together.

 

[arch252]

Thanks Rivets, I know this stuff is old hat to you guys and I'm sure it tiresome dealing with people like me with just enough sense to be dangerous. I'm trying to learn though.

 

[bertsmobile1]

OK,
A couple of questions .
Was it working before ?
If so how did you stop it ?
You said the wire to the ignition was "Hot" bu that do you mean it gets 12 V when you turn the ignition on and goes 0 V with the ignition off ?

If it is a kettering system ( battery coil ) then the ignition switch will supply 12 V to turn on the sparks
If it is a magnet ignition then the wire from the ignition switch will go open to turn on the sparks and close to ground to turn the sparks off.

I am not familiar with this particular engine but will do some digging tonight ( your Mon morning ) and get back to you tommorrow.
Right now I am up to my arm pits in a Bolens/ Troybult Duratrack which is giving me much grief.

 

[arch252]

Thanks Bert. This was not running when I got it. I was told they took it in on trade with no history and they determined "it needs a coil". It had no spark. The points were not making contact so I had to clean them. I don't know how they could determine that it needed a coil when the points were not even grounding.

So the wire coming from the key start was not connected but was routed to and hanging down near the points and condenser so i don't know where else it might connect.

I have a fresh battery reading 12.53 VDC. With the key switch off that wire reads 0 VDC. When I turn the key to the run position. The wire reads .108 VDC and when I move the switch over to the start position the wire bumps up to .150 VDC.

I thought the wire would connect to the condenser to bump up the volts a little to increase the spark, but I don't really know if it works that way or not.

I feel confident the one wire coming from the magneto (not the spark plug wire of course) connects to both the points and condenser.

If the wire from the key start is supposed to go to the condenser as well, is there any problem with the way I have it wired in the photo in the first post? Can I connect the points, the magneto and the key switch wires together all at the condenser tab?

 

[bertsmobile1]

You disconnect the kill wire and rotate the engine .
No spark = bad coil on the assumption that the points have been replaced with an electric trigger.

What do you get between ground and that wire with the ignition on & off. ?

Assemble as is.
Condensers go parallel to the points .
They are there to prevent arcing & thus burning as the points open or close.
It should produce a spark with that wire sitting loose and no spark with that wire grounded.
Use your Ohm meter to measure the resistance of the secondary winding in the coil by placing one end on the Plug cap and the other on the place where the winding from the coils are grounded to the laminations.
Then do the same from the wire that goes from the coil to the points and the same grounding place on the coil.
I have not read the manual Rivets posted but there should be readings for primary ( points to coil ) and secondary ( plug to coil ) resistances.
They should both be between 2 & 10 ohms
If you get 0 reading or an infinate ( overlaod ) reading then the winding is either short circuit or open circuit.
Again you can do both of these without cleaning the points.
After that you measure from the other side of the points to make sure you are making & breaking a circuit as the points open & close.

 

[ILENGINE]

Some of the troybilt tillers were set up with a three position key switch. So you could have a wire going from the key switch to the points/condensor, which is to kill the engine when you turn the key off.. A wire going from the points/condensor to the kill system on the throttle lever, which kills the engine when pulled all the way to the stop position, and a wire going from the points/condensor to the module next to the flywheel . Be aware that if battery voltage has been introduced to this system the module next to the flywheel is cooked.

Some systems were set up with a two position key switch and in that case there shouldn't be a wire from the points to the switch. For testing disconnect all the wire except the wire going from the module to the points/condensor and see if you have fire. If your haven't replaced the points and condensor I would do that next, and if that fails then replace the module itself.

then system is started by advancing the throttle, turning the key to the start position or by turning on the key, and using the rope to start the engine.

 

[arch252]

Thank you both for the information, very good stuff. ILengine, You may be on to something. While I checked the voltage on that wire coming from the key switch and it was a very nominal .108 VDC, I did not check it for ground in the off position. I assumed the key switch itself was grounded and that killed the engine when the switch was in the off position but I could see an application where a wired kill switch might be more reliable. I will check that when I get home. Sending out a tenth of a volt in the run position sure doesn't make sense to me, I don't know how that would be useful. If it is a ground wire that would really explain everything and then I would imagine that wire could be connect anywhere within that circuit.

Let me get back to this reoccurring question, the wiring diagram shows the wire coming from the points splitting in two, one wire going to the condenser and the second going to the magneto. Does it matter at all if (for simplicity) I have all of these wires connect at the condenser tab? By that I mean the wire from the points, the wire to the magneto, and the wire coming from the key switch (assuming that it is indeed a ground) all three connecting at the tab on the condenser.

Once I know the wiring is correct then I am going to attempt to diagnose the lack of spark. I plan to attempt some of the testing that Bert described.

 

[bertsmobile1]

0.1 V is in the vicinity of leakage inside the switch due to accumulation of conductive debris or semi conductive corrosion products.
Flood the switch with some cleaning / dewatering fluid like WD 40 and that 0,1 V will most likely vanish.
I have a stash of Rover Rancher 2's and they all have the cut out on the throttle as you would have on a push mower engine.
So no excuses for me not twigging to it.
Looks like Ilengine will this months Freddo Frog award. :thumbsup:

 

[arch252]

I tested the wire from the key switch. In the off position it is grounded. It breaks ground in the run and start positions. Unless you tell me otherwise I'll assume it's okay to connect the key switch ground, points and magneto ground wires all together at the condenser.

Many thanks to ILENGINE for spotting that for me.

I have found and electronic ignition kit to do away with the points and condenser. It's part number
2575710S Electronic Ignition Kit by Kohler. If I was going to replace the condenser anyway for $20 I thought about spending $50 for the kit. Wondering if anyone had experience with it and if I should change that.

If the new consdenser doesn't give me spark I guess I'll look at this impossible to find magneto.